Modified Final Version
Development of gold particles at varying precursor concentration
Mubarak Ali a,* and I-Nan Linb
a
Department of Physics, COMSATS Institute of Information Technology, Islamabad
45550, Pakistan.
b
Department of Physics, Tamkang University, Tamsui Dist., New Taipei City 25137,
Taiwan (R.O.C.).
*corresponding address: [email protected], [email protected] , Ph. +92-51-90495406
Abstract –Coalescence of tiny particles into extended shapes has been an overlooked
phenomenon since long. Present study discusses the formation of tiny shaped particles
and their packing into large-sized particles under varying concentration of gold
precursor in homemade built pulse-based electronphoton-solution interface process.
Under fixed ratio of bipolar pulse OFF to ON time, the amount of precursor decides tiny
shaped particles. At air-solution interface, tailored energy-shape photons cropped atoms
of monolayer assembly into tiny particles of connecting equilateral triangles in each
case. For precursor concentration between 0.07 mM to 0.90 mM, a large number of tiny
particles are made in two connecting equilateral triangles, maximum at 0.30 mM and
0.60 mM. On division into triangular-shaped tiny particles while self-bearing field force
elongated at electron-solution interface followed by packing under uniform drive into
various geometric anisotropic shaped particles at center of photon-solution interface. In
the course of packing, travelling photons of hard X-rays modified elongated structure
into smooth elements at photon solution interface. At 0.05 mM and 1.20 mM, tiny
particles rarely observed are made in tiny shaped particles, their non-uniform drives
resulting into pack where distorted particles were developed. Changing argon gas flow
rate does not influence the shape of particles but structure at minute level, apparently.
Reflected photons patterns at the surface of various geometric anisotropic shaped
particles validate formation of smooth elements and in case of distorted ones, it does
1
not. This study purely determines that under what concentration of gold precursor a
certain size and shape of tiny-sized particle and large-sized particle is required while
utilizing tailored energy-shape photons.
Keywords: precursor concentration; tailored energy-shape photons; tiny particles;
dynamics; tiny shaped particles; two-dimensional materials.
Introduction:
Possible structural change in any material is an unusual phenomenon and to control the
shape of colloidal particles is a great challenge. To assemble tiny particles precisely is
an ultimate goal for developing advanced functional materials. Metallic colloids in
different shapes under varying concentration of precursor may indicate unexplored
factors responsible for their development. When material is shaped due to atom-to-atom
amalgamation, attained dynamics of atoms should be the main cause to manipulate
both shape and structure of tiny particle. It is expected that varying the concentration of
gold precursor in appropriate range may result into depict the overall picture of size and
shape of particles.
Several approaches have been enlisted in the literature to synthesize colloidal tinysized particles and large-sized particles where citrate reduction method is one of the
most widely adopted procedures [1]. Development of large-sized particles on likely
coalescence of tiny-sized particles has been the subject of several studies [2-12]. Metal
clusters behave like simple chemical compounds and could find several applications in
catalysis, sensors and molecular electronics [2]. Discrete features of nanocrystals and
their tendency to extend into superlattices suggest ways and means for the design and
fabrication of advanced materials with controlled characteristics [3]. An ordered array of
nanoparticles instead of agglomerate might present new properties different from the
individual particles [4]. Coalescence of nanocrystals into extended shapes has been
appeared to be a realistic goal [5]. Self-assembly means to design specific structure,
which cannot be achieved alternatively [6]. Potential long-term use of nanoparticle
technology is to develop small electronic devices [7]. Assembling of nanoparticles may
be an initial effort towards selective positioning and patterning at large area [8].
Organization of nanometer size building blocks into specific structures to construct
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functional materials and devices is one of the current challenges [9]. On assembling
nanocrystals into useful structures ‘atoms and molecules’ will be treated as materials of
tomorrow [10]. Precise control on the assemblies of nanoparticles enables synthesis of
complex shapes and will provide pathways to fabricate new materials and devices [11].
Coalescing nanocrystals into long-range crystals allow one to develop materials with
endless selections [12]. Anisotropic shapes have the size-dependent surface plasmon
absorption, but it remained challenging to take benefit of the phenomenon at
macroscopic level [13].
On trapping mobile electrons, tiny particles of gold collectively oscillate [14]. The
existing mechanistic interpretations are insufficient to explain several observations and
rate of reactant addition/reduction can be estimated to produce subsequent specific
shaped particles in high yields [15]. On locating the specific mode of excitation of
surface plasmon in metallic nanocrystals will bring intense consequences on the
research fields [16]. More work is required to develop in-depth understanding of metallic
colloids [17].
Attempts have also been made to synthesize different geometric anisotropic shapes
and distorted shapes of the nanoparticles/particles in different employed plasma
solution processes [18-25] where mainly four strategies remained under utilization; DC
plasma discharge in contact with the liquid, DC glow discharge plasma in contact with
liquid, pulse plasma discharge inside the liquid, and gas-liquid interface discharge.
Quite a few reaction mechanisms were proposed by different groups are to be the most
probable underlying mechanism such as plasma electrons [20], hydrogen radicals in
liquid [22], aqueous electrons [21] and hydrogen peroxide [18, 19]. Gold nanoplates and
nanorods have been synthesized at the surface of solution while spherical-shaped
particles inside the solution [22]. Again, probing matter at a length scale comparable to
the subwavelength of light can deliver phenomenal optical properties [26, 27] and
different phase-controlled syntheses give an improved catalytic activity of metal
nanostructures as compared to bulk ones [28, 29].
Present study deals developing tiny shaped particles and tiny non-shaped particles
as well made under varying concentration of gold precursor following by development of
various geometric anisotropic shaped particles and distorted particles. We briefly
3
discussed the role of different precursor concentration under the ‘tailored energy-shape
photons’ while developing various gold nanoparticles and particles.
Experimental details:
Solid powder of HAuCl4 was purchased from Alfa Aesar to obtain the aqueous solutions
of different molar concentrations. Briefly, aqueous solution of about one gram
HAuCl4·3H2O and ~ 100 ml DI water was prepared in a glass bottle. This was followed
by the preparation of several different molar concentrations by dissolving various
amounts of precursor in DI water in such a way that total quantity of solution obtained
each time was ~ 100 ml.
Schematic of homemade methodology is shown in Figure 1. A copper capillary with
internal diameter ~ 3 mm (outer diameter: ~ 6 mm) was used to maintain the flow of
argon gas. At the bottom of tube the argon gas atoms splitted under field of photonic
current. A graphite rod with a width of 1 cm was used to maintain the required field to
split flowing inert gas atoms. The distance between copper capillary bottom and solution
surface was ~ 0.5 mm and kept constant in all experiments. Distance between graphite
rod and copper capillary was set ~ 4 cm and was kept constant in each experiment.
Layout of air-solution interface and electronphoton-solution interface is shown
elsewhere [30].
Bipolar pulse of fixed ON/OFF time was controlled by the pulse DC power controller
(SPIK2000A-20, MELEC GmbH; Germany). Input DC power was provided by
SPIK2000A-20. Symmetric-bipolar mode of pulse power controller was employed and
equal time periods of pulses was set; ton (+/-) = 10 µsec and toff (+/-) = 10 µsec. The
input power slightly fluctuated, initially. Fluctuation of input power was highest at the
start of the process, dropped to nearly half in a second and remained almost stable in
the remaining period where split of inert gas atoms were controlled auto throughout the
process under the running voltage (32 V and noted current 1.3 A), which was enhanced
~ 40 times by employing step-up transformer. The variation in power was more or less 1
% throughout processing solution for each concentration of precursor.
Temperature of the solution was recorded with laser-controlled temperature meter
(CENTER, 350 Series). In each experiment, temperature was measured at the start (~
4
20 °C), middle (~ 27 °C) and at the end (~ 37 °C) of process with ±1 °C accuracy.
Different molar concentrations prepared (~ 0.10 mM, ~ 0.30 mM, ~ 0.60 mM, ~ 0.90 mM
and ~ 1.20 mM) where duration of the process was 10 minutes and kept constant in
each experiment. Total argon gas flow rate was 100 sccm and maintained through
mass flow controller. Different molar concentrations were also prepared (~ 0.07 mM, ~
0.10 mM, ~ 0.30 mM and ~ 0.60 mM) while maintaining argon gas flow rate 50 sccm.
Copper grid covered by carbon film was used and samples were prepared by dipcasting. Samples were placed into Photoplate degasser (JEOL EM-DSC30) for ~ 24
hours to eliminate moisture. Bright field transmission microscope images, selected area
photons reflection (SAPR; known as SAED patterns) and high resolution transmission
microscope images were taken under the application of microscope known as HR-TEM
(JEOL JEM2100F) while operating at 200 kV.
Results and discussion:
Layout of a pulse-based electronphoton-solution interface process is shown in Figure 1
where nanoparticles/particles developed under varying concentration of gold precursor.
At precursor concentration of 0.05 mM, spherical-shaped nanoparticles/less-distorted
shapes were developed as shown in various bright field transmission microscope
images (a-d) of Figures S1 and their average size is between 20 to 25 nm. On
increasing the concentration of precursor upto 0.10 mM, the average size of different
particles increased and many of them developed into geometric anisotropic shapes as
shown in bright field transmission microscope images of (a-c) of Figure S2. On
increasing the precursor concentration from 0.10 mM to 0.30 mM, the average size of
particles (different shape) further increased and their bright field transmission
microscope images (a, b) are shown in Figure 2; triangle-, hexagon-, isosceles
trapezoid-, rhombus-, pentagon-, rod- and belt-shaped particles developed. Some of the
shapes reveal high aspect ratio. The increase in the size of different geometric
anisotropic shapes is mainly related to packing of large-sized triangular-shaped tiny
particles. Several high aspect ratio shapes are shown in various bright field
transmission microscope images (a-f) of Figures 3 along with SAPR patterns (A-F in
Figure 3); each image shows a unique geometric anisotropic shape along with SAPR
5
pattern. SAPR patterns of various geometric anisotropic shapes indicate modification of
their structure into smooth elements. In Figure 3 (g), difference in the lengths of
particles’ sides were only in the margin of an atoms/or few atoms indicating packing of
tiny particles of same size and shape under the maintenance of equal rate at all sides
while developing (triangle- and hexagon-shaped). In some cases, the particle shapes
bond via sides (Figure 3h) and in other cases, overlaid (Figure 3i). For precursor
concentration 0.90 mM, particles of different geometric anisotropic shapes are shown in
bright field transmission microscope images (a-h) of Figure S3, which reveal the similar
shapes of particles as in the case of precursor concentrations 0.10 mM, 0.30 mM and
0.60 mM except that they have slightly lower aspect ratios. At 1.20 mM, very large size
tiny particles packed under non-uniform drives resulted into develop highly-distorted
particles as shown in various bright field transmission microscope images (b-j) of Figure
4. Only the hexagon-like shape reveals the geometric anisotropic shape (Figure 4a).
SAPR patterns of different particles’ shape show different orientation of the structure
and diffraction patterns shown in Figures 4 (a) and (b) indicate made smooth elements
in different orientation as well (in Figure 4A) and Figure 4B) and in only few square
nanometers area. However, the formation of smooth elements in few square
nanometers spoiled in the case of distorted particles shown in Figures 4 (c) and (d), and
their SAPR patterns shown in Figure 4 (C) and Figure 4 (D) presented information about
surface structure where reflected photons spotted in the form of intensity spots. The
packing of large-sized tiny particles reveal no specific geometry of shape as shown in
Figure 4 (d). Distorted particle shape like flower is shown in Figure 4 (e) and several
particles in identical features are shown in Figure 4 (i). In Figure 4 (e), an average size
of tiny particle is 50 nm, which have highly disordered structure.
The processed solutions under different molarities of precursor’s concentration are
shown in Figure S4 (left to right: 0.05 mM, 0.10 mM, 0.30 mM, 0.60 mM, 0.90 mM and
1.20 mM). Besides 100 sccm, solutions were also processed at 50 sccm argon gas flow
rate and different colors of the solutions are shown in Figure S5 (left to right: 0.07 mM,
0.10 mM, 0.30 mM and 0.60 mM), whereas, bright field transmission microscope
images of nanoparticles and particles shapes are shown in Figures S6-S9. A different
color of each solution is related to overall size and shape of particles along with their
6
quantity, where modes of refraction and reflection of travelling light determine the
certain nature of that color (observed). Various distorted-shaped particles as well as
geometric anisotropic shaped particles developed at 50 sccm reveal identical features
to the ones developed at 100 sccm. In Figures S6, S7 and S9, some of the shapes
developed lengths of sides in the precision of an atom/few atoms, for example, a
triangular-shaped
particle
in
Figure
S9
(g).
Several
different
shapes
of
nanoparticles/particles are shown in Figure S10 (a). A triangular-shaped nanoparticle
encircled in Figure S10 (a) was dealt with high resolution transmission microscope
image as in Figure S10 (b) where width of each smooth element is ~ 0.12 nm equal to
inter-spacing distance. In SAPR patterns of particles, shapes other than rod-like shape,
distance between parallel printed intensity spots is ~ 0.24 nm as labeled in Figures 3 (AC), Figure 4 (A) and also in Figure S3 (B). On the other hand, the distance between
parallel printed intensity spots (which are now intensity lines) in the case of rod-shaped
particles is ~ 0.27 nm as shown in Figure 3 (F) and also in Figure S3 (E).
However, it appears from the feature of different shaped nanoparticles/particles as
they are darker in the case synthesized at 50 sccm where rate of elongation of tiny
shaped particles as well as rate of travelling hard X-ray photons slightly reduced due to
lower concentration of flowing argon gas. At 100 sccm argon flow rate, both electrons’
quantity as well as travelling photons at interface increased resulting into sharp and flat
formation of the smooth elements of structure of various shapes.
Orientation-dependent packing at uniform drive of tiny particles prevailed in any
geometric anisotropic shaped particle can be drawn from the distributed intensity spots
in SAPR pattern. In Figure S3 (C), SAPR pattern also revealed reflected pattern of
structure underneath hexagonal-shaped particle, in same shape, where photons (not
electrons) reflected at the surface of structure of smooth elements in the abovepositioned particle as well as the underneath one; in the case of latter, it is clear that
photons reflected at the surface of underlying structure while entering through interspacing distance of smooth elements of above-positioned particle. In
pulse-based
electronphoton-solution interface process, gold atoms dissociated from the precursor
and amalgamated at air-solution interface depending on the localized process
parameters.
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Splitting argon atoms switched propagating photons characteristic current to
travelling increasing wavelength photons on leaving inter-state electron’s gap, thus,
revealing the glow of light on reaching their wavelength in the visible range [31].
Photons characteristic current configure their ‘force energy’ in inter-state electron’s gap,
thus, propagate between two electron states [32]. The amalgamated atoms bind under
the heat energy of suitable merged photons or squeezed photons [33]. On
amalgamation of atoms depending on set precursor concentration, they evolve
geometric structure of tiny particles under the ‘tailored energy-shape photons’ resulted
in each set pulse ON time. A ratio of pulse OFF to ON time delivers a tailored energy
photon shape-like two connecting equilateral triangles, thus, resulting into crop atoms of
monolayer assembly in the shape of two connecting equilateral triangles of a tiny
particle. Such tiny particle divide into two equal triangular-shaped tiny particles prior to
go for elongation at electron-solution interface resulting into alter them in suitable
electronic structures where elongation of all atoms were uniform, thus, they modified
into smooth elements while travelling hard X-rays photons at photon-solution interface
[34]. Carbon atoms bind as well in tiny grains, grains or crystallites under the suitable
localized heating as given elsewhere [35, 36], then in other related studies of gold [3739], silver and binary composition of gold silver [37].
At the lowest concentration of precursor (0.05 mM) very few gold atoms were
available, which evacuated at interface but the tailored photons possess the same size
and energy under set ratio of bipolar pulse resulting into crop tiny particles which didn’t
possess shape of two connecting equilateral triangles. The atoms below those photons
are insufficient dealing an average size of tiny particle ~ 1.3 nm with no specific shape.
Thus, dynamics of the process at unity ratio of pulse OFF to ON time do not let to
evolve tiny particle shape in two connecting equilateral triangles at 0.05 mM. As shown
in Figure 5 (a1) such tiny particles do not evolve in triangle shape. Obviously, under the
process of synergy as well as impinging electron streams from the regular external
source, their atoms elongated as well as deformed as shown in Figure 5 (a2) and, their
packing under non-uniform
drives
resulted
into
less-distorted/spherical-shaped
nanoparticle (Figure 5a3). At fixed bipolar pulse ON/OFF time, increasing the precursor
concentration from 0.07 nm to 0.90 mM, a large number of tiny particles were made in
8
two connecting triangles for each where the size of such tiny particles increased on
increasing the precursor concentration, however, in certain regions tiny particles were
also made in no specific shape due to uneven distribution of atoms per unit area and
they are said to be moderately-disordered tiny particle as shown in Figure 5 (b1). Such
tiny particle doesn’t divide into two equal triangular-shaped tiny particles as a tiny
particle having two connecting triangles can only divide into two equal equilateral
triangular-shaped tiny particles under self-bearing the minute difference of field force.
Obviously, such tiny particles don’t elongate uniformly as sketched in Figure 5 (b2) and
said to be moderately-distorted tiny particle. So, they pack under non-uniform drives
where moderately-distorted particle were developed as shown in Figure 5 (b3).
At 1.20 mM, precursor concentration is very large and assembly of atoms made at
air-solution doesn’t reveal compact monolayer, it contained disorderness which was at
greater extent at initial stage of the process, thus, resulted tiny particles under the
application of same ‘tailored energy-shape photons’ resulted into crop highly-disordered
tiny particles. A highly-disordered tiny particle neither evolve in shaped geometry nor
two-dimensional as shown in Figure 5 (c1) where groups of atoms (total atoms: 171)
were arranged in different orderings. Thus, a highly-disordered tiny particle elongated in
various orientations as well and termed as highly-distorted tiny particle as show in
Figure 5 (c2). Packing of such tiny particles under non-uniform drives resulted into
highly-distorted particle as shown in Figure 5 (c3).
A connected triangular-shaped tiny particle is shown in Figure 5 (d1). Under the
difference of the field force behavior, it was divided into two equal equilateral triangularshaped tiny particles and impinging electron streams elongated them uniformly. A tiny
particle elongated at 60° angle is shown Figure 5 (d2). Six uniformly elongated tiny
particles arriving from the same orientations (at 60° angle) from six different zones
nucleated the hexagonal-shaped particle at the center of pulse-based electronphotonsolution interface process as shown in Figure 5 (d3). Packing of several such tiny
particles under retaining intact initially originated symmetry resulted into evolution of
hexagonal-shaped particle. Photons wavelength in hard X-rays while travelling at
interface and in the course of placing over developing geometric anisotropic shaped
particles resulting into modify their electronic structure into smooth elements as shown
9
in Figure 5 (d4); width of the smooth element and inter-spacing distance is ~ 0.12 nm,
which is the same as shown in Figure S10 (b) where the widths are measured with
original scale marker. Further details of formation of smooth elements on modification of
elongated structure are given elsewhere [34] along with greater measured inter-line
distance in the photons printed energy patterns in one-dimensional shape where low
degree packing prevails to inter-dot distance in the photons printed energy patterns in
two-dimensional shape where higher degree packing prevails [39].
On terminating the packing of developing large-sized particles sink under free fall.
The developing of various geometric anisotropic shaped particles and their sinking
enables arriving new stock of gold atoms at air-solution interface under levitation
behavior, thus, forming new monolayer assembly at air-solution interface under neutral
behavior of levity-gravity. These geometric anisotropic shaped particles validating the
behavior of levitation and gravitation exist at electronic level in the development process
and further detail of these behaviours are discussed elsewhere [40]. Again, a recent
study reveals the impact of such field force behaviours at electronic level while using
nanoparticles as nanomedicine applications [41].
Under very high concentration of gold precursor (1.20 mM), at the start of process
average size of tiny particles was 50 nm and on prolonging the process time resulted
into tiny particles having decreased size, discussed elsewhere [32]. Therefore, the
geometric anisotropic shaped particle shown in Figure 4 (a) is due to smaller size tiny
particles shape in triangle developed at the later stage of the process. This indicates
that by increasing the process duration, the favorable conditions prevailed and tiny
particles of disordered structure turned into ordered structure under envisaging
favorable conditions of the process following by dividing into triangular-shaped tiny
particles prior to go for elongation and packing. Therefore, initial concentration of
precursor is not the only parameter controlling the geometry of tiny particles and it
depends on time-to-time change in the precursor concentration too. It has been pointed
out that upto certain numbers of atoms tiny particles are made in hcp structures [42] and
tiny particle size upto a point shows metallic character [43]. It has been acknowledged
that besides geometry and entropy, progress research efforts are considering the use of
geometry and entropy to explain not only structure but also dynamics [44] and
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disordered jammed configuration is not the only one in any known protocol but there are
also ordered metrics, which characterize the order of packing [45].
From the application point of view, nanoparticles/particles having distorted shapes
reveal potential in various catalytic applications, whereas, those in geometric anisotropic
shapes have potential for being used as ultra-high-speed devices along with their
diversified applications in many areas of optics, medical and photonic devices, etc.
Again, electronic structures of tiny particles under varying concentration of precursor
may change catalytic activities, as different size of tiny particles may have different
behaviors. Effects of varying ratios of pulse OFF to ON time on the tiny shaped particles
along with development of extended shapes having various sorts of features have been
discussed elsewhere [38]. Here term ‘extended shapes’ refer to particles having both
distorted shapes and geometric anisotropic shapes in varying size and don’t include
single tiny particle or building block that evolves at the first stage of the process
following division into triangular-shaped tiny particles.
Conclusions:
A certain amount of precursor concentration under the fixed ratio of bipolar pulse OFF
to ON time results into formation of a tiny shaped particle having two connecting
triangles, which divides into two equal triangular-shaped tiny particles under self-bearing
the opposite field force behavior. By increasing the molar concentration of gold
precursor from 0.05 mM to 1.20 mM, the average size of gold tiny particles increases
from ~ 1.3 nm to ~ 50 nm where arisen dynamics of the process have pronounced
effects on the formation of their tiny shaped particles. At 0.05 mM, tiny particles do not
made in triangle shape and their packing results into less-distorted spherical-shaped
nanoparticles. At 0.07 to 0.90 mM, a large number of tiny particles are made in
connecting triangles resulting into divide in two equilateral triangular-shaped tiny
particles for each case and their maximum trend is observed at 0.30 mM and 0.60 mM.
On impinging electron streams to divided triangular-shaped tiny particles elongate
resulting into pack into various geometric anisotropic shaped particles as per acquired
orientations of packing under uniform drive. At 1.20 mM, a large number of tiny particles
were not made in connecting triangles, so they didn’t divide into two triangular-shaped
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tiny particles as well as didn’t pack under uniform drive, thus, they evolve distorted
particles while packing under non-uniform drives of highly-distorted tiny particles and
SAPR patterns of their particles agreed that they possess undefined structure. At
precursor concentration 0.30 mM and 0.60 mM, maximum tiny particles are made in
connecting triangles for each case where they divided into two triangular-shaped tiny
particles as well, thus, maximum particles are developed in geometric anisotropic
shapes. On decreasing argon gas flow rate from 100 sccm to 50 sccm doesn’t influence
the overall behavior of developing particles. The color of the solution is changed due to
the overall impact of configuring modes of refraction and reflection of incident light
through the certain size and shape particles available in that solution. Overall, under
varying the concentration of gold precursor changed the behavior of made monolayer
assembly at air-solution interface resulting into alters the size and shape of particles
where ‘tailored energy-shape photons’ placing horizontally remained the same along
with other process conditions.
Acknowledgements:
Mubarak Ali thanks National Science Council (now MOST) Taiwan (R.O.C.) for
awarding postdoctorship: NSC-102-2811-M-032-008 (August 2013- July 2014). Authors
wish to thank Dr. Kamatchi Jothiramalingam Sankaran, National Tsing Hua University
and Mr. Vic Chen, Tamkang University, Taiwan (R.O.C.) for assisting in transmission
microscope operation. Mubarak Ali greatly appreciates useful suggestions of Dr. M.
Ashraf Atta while writing the paper.
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32. Ali, M (2017) Revealing the Phenomena of Heat and Photon Energy on Dealing
Matter at Atomic level. http://www.preprints.org/manuscript/201701.0028/
33. Ali, M (2016) Structure evolution in atoms of solid state dealing electron transitions.
http://arxiv.org/abs/1611.01255.
34. Ali, M. (2016) The study of tiny shaped particle dealing localized gravity at solution
surface. http://arxiv.org/abs/1609.08047.
35. Ali M, Lin, I N (2016) Phase transitions and critical phenomena of tiny grains thin
films synthesized in microwave plasma chemical vapor deposition and origin of v1
peak. http://arXiv.org/abs/1604.07152.
36. Ali M, Ürgen, M (2016) Switching dynamics of morphology-structure in chemically
deposited carbon films-a new insight. http://arxiv.org/abs/1605.00943.
37. Ali M, Lin, I N (2016) Tapping opportunity of tiny shaped particles and role of
precursor in developing shaped particles. http://arxiv.org/abs/1605.02296.
38. Ali M, Lin, I N (2016) Controlling morphology-structure of particles at different pulse
rate, polarity and effect of photons on structure. http://arxiv.org/abs/1605.04408.
39. Ali M, Lin, I N (2016) Formation of tiny particles and their extended shapes-origin of
physics and chemistry of materials. http://arxiv.org/abs/1605.09123.
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40. Ali, M (2017) Why some atoms are in gaseous state and some in solid state but
carbon work on either side. (Submitted for consideration)
41. Ali, M. Nanoparticles –Photons: Effective or Defective Nanomedicine. Preprints
(2017). http://www.preprints.org/manuscript/201703.0174/v1
42. Negishi Y, et al. (2015) A Critical Size for Emergence of Nonbulk Electronic and
Geometric Structures in Dodecanethiolate-Protected Au Clusters. J. Am. Chem.
Soc. 137; 1206-1212.
43. Moscatelli A (2015) Gold nanoparticles: Metallic up to a point. Nature Nanotechnol.
DOI:10.1038/nnano.2015.16.
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349; 1253751.
45. Atkinson S, Stillinger, F H, Torquato S (2015) Existence of isostatic, maximally
random jammed monodisperse hard-disk packings, Proc. Natl. Acad. Sci. U.S.A.
Pulse power controller
DC Power supply
Argon gas
111; 18436-18441.
Copper tube
Height:
~ 13 cm
Diameter of beaker: 10.5 cm
Diameter of glow: 3 mm
Height: 100
ml ~1 cm
Step-up transformer
Graphite rod:
2
1cm
Cover
4.00 cm
Water surface
area: 346 cm2
Electronphoton-solution interface
(HAuCl4:3H2O + DI water)
Figure 1: Schematic of pulse-based electronphoton-solution interface process.
16
Figure 2: (a) & (b) Bright field transmission microscope images of nanoparticles/particles made in
various geometric anisotropic shapes and distorted shapes; precursor concentration 0.30 mM and argon
gas flow rate 100 sccm.
17
18
19
20
Figure 3: (a-i) Bright field transmission microscope images of particles showing mixed behavior of
geometric anisotropic shapes and distorted shapes along with SAPR patterns (A-F); precursor
concentration 0.60 mM and argon gas flow rate 100 sccm.
21
22
23
Figure 4: (a-j) Bright field microscope images of particles showing mixed behaviour of distorted
particles (except in ‘a’)/ SAPR patterns (A-D); precursor concentration 1.20 mM and argon flow rate 100
sccm.
24
Development of geometric
anisotropic shaped particle
Development of less-, moderatelyand highly-distorted particles
(d)
(a)
(3)
(2)
(2)
(1)
(1)
(b)
(4)
(3)
(3)
(1)
(2)
(c)
(3)
(2)
(1)
Figure 5: (a1) Less-disordered tiny particles, (a2) elongation of ‘less-disordered tiny particles’ nonuniformly, (a3) less-distorted particle; (b1) Moderately-disordered tiny particle, (b2) elongation of
‘moderately-disordered tiny particle’ non-uniformly, (b3) partially-distorted particle; (c1) Highly-disordered
tiny particle, (c2) elongation of ‘highly-disordered tiny particle’ non-uniformly, (c3) highly-distorted particle;
(d1) connecting triangles tiny particle divide into two equal triangular-shaped tiny particles under
difference of minute opposite field force behavior, (d2) elongation of triangular-shaped tiny particle
uniformly, (d3) nucleation of hexagonal-shaped particle and (d4) particle of structure of smooth elements.
25
Authors’ biography:
Mubarak Ali graduated from University of the Punjab with B.Sc. (Phys& Maths) in 1996 and
M.Sc. Materials Science with distinction at Bahauddin Zakariya University, Multan, Pakistan
(1998); thesis work completed at Quaid-i-Azam University Islamabad. He gained Ph.D. in
Mechanical Engineering from Universiti Teknologi Malaysia under the award of Malaysian
Technical Cooperation Programme (MTCP;2004-07) and postdoc in advanced surface
technologies at Istanbul Technical University under the foreign fellowship of The Scientific and
Technological Research Council of Turkey (TÜBİTAK; 2010). He completed another postdoc in
the field of nanotechnology at Tamkang University Taipei (2013-2014) sponsored by National
Science Council now M/o Science and Technology, Taiwan (R.O.C.). Presently, he is working
as Assistant Professor on tenure track at COMSATS Institute of Information Technology,
Islamabad campus, Pakistan (since May 2008) and prior to that worked as assistant
director/deputy director at M/o Science & Technology (Pakistan Council of Renewable Energy
Technologies, Islamabad; 2000-2008). He was invited by Institute for Materials Research (IMR),
Tohoku University, Japan to deliver scientific talk on growth of synthetic diamond without
seeding treatment and synthesis of tantalum carbide. He gave several scientific talks in various
countries. His core area of research includes materials science, physics & nanotechnology. He
was also offered the merit scholarship (for PhD study) by the Government of Pakistan but he
couldn’t avail. He is author of several articles published in various periodicals
(https://scholar.google.com.pk/citations?hl=en&user=UYjvhDwAAAAJ) and also a book.
I-Nan Lin is a senior professor at Tamkang University, Taiwan. He received the
Bachelor degree in physics from National Taiwan Normal University, Taiwan, M.S.
from National Tsing-Hua University, Taiwan, and the Ph.D. degree in Materials
Science from U. C. Berkeley in 1979, U.S.A. He worked as senior researcher in
Materials Science Centre in Tsing-Hua University for several years and now is faculty
in Department of Physics, Tamkang University. Professor Lin has more than 200
referred journal publications and holds top position in his university in terms of
research productivity. Professor I-Nan Lin supervised several PhD and Postdoc
candidates around the world. He is involved in research on the development of high
conductivity diamond films and also on the transmission microscopy of materials.
26
Supplementary Materials:
Figure S1: (a-d) Bright field transmission microscope images of nanoparticles showing various lessdistorted shapes; precursor concentration 0.05 mM and argon gas flow rate 100 sccm.
27
Figure S2: Bright field transmission microscope images of nanoparticles showing mixed behavior
various geometric anisotropic shapes and distorted shapes; precursor concentration 0.10 mM and argon
gas flow rate 100 sccm.
28
29
30
31
Figure S3: Bright field transmission microscope images of particles showing mixed behavior of various
geometric anisotropic shapes and distorted shapes along with SAPR patterns (A-F); precursor
concentration 0.90 mM and argon gas flow rate 100 sccm.
Figure S4: Different color of solutions processed under different molar concentration of precursor (0.05
mM, 0.10 mM, 0.30 mM, 0.60 mM, 0.90 mM and 1.20 mM, left to right) and argon gas flow rate 100 sccm.
32
Figure S5: Different color of solutions processed under different molar concentration of precursor (0.07
mM, 0.10 mM, 0.30 mM and 0.60 mM, left to right) and argon gas flow rate 50 sccm.
33
Figure S6: Bright field transmission microscope images of nanoparticles showing mixed behavior of
various geometric anisotropic shapes and distorted shapes; precursor concentration 0.07 mM and argon
gas flow rate 50 sccm.
34
Figure S7: Bright field transmission microscope images of nanoparticles showing mixed behavior of
various geometric anisotropic shapes and distorted shapes; precursor concentration 0.10 mM and argon
gas flow rate 50 sccm.
35
Figure S8: Bright field transmission microscope images of nanoparticles/particles showing mixed
behavior of geometric anisotropic shapes and distorted shapes; precursor concentration 0.30 mM and
argon gas flow rate 50 sccm.
36
37
Figure S9: Bright field transmission microscope images of particles showing mixed behavior of various
geometric anisotropic shapes and distorted shapes; precursor concentration 0.60 mM and argon gas flow
rate 50 sccm.
Figure S10: (a) Bright field transmission microscope image of nanoparticles/particles showing mixed
behavior of various geometric anisotropic shapes and distorted shapes at 0.10 mM and (b) magnified
high resolution transmission microscope image taken from the encircled triangle in ‘a’ shows equal widths
of smooth elements and inter-spacing distance; precursor concentration 0.10 mM and argon gas flow rate
50 sccm.
38