Role of micro-concentration field on morphology of silver particles

doi:10.11949/0438-1157.20200090

Abstract

Abstract:

To reveal the role of interface micro-concentration distribution on the evolution of materials structure, silver crystallization was investigated by the in-situ optical microscopy and lattice Boltzmann simulations. Silver particles were synthesized by electrodeposition, in which silver oxide colloid particles were generated as the by-products. The migration velocity of colloid particles in the electrolyte was regulated by the electric field. With the increase of migration velocity of colloid particle, mass transfer increased, the diffusion layer in the front of the growth became thinner, and the concentration gradient became sharper. As a result, the morphology of silver particles changed from spherical nanocrystals to symmetrical dendrites, and the growth rate increased from 10 μm²/s to 60 μm²/s simultaneously. Finally, it was proposed that the micro-concentration field in the diffusion layer is the main mechanism dominating the evolution of particle morphology, which was verified by the lattice Boltzmann simulation of convection diffusion and phase transition.

Key words: micro-concentration field, silver particle, in-situ investigation, dynamic growth, morphology evolution, concentration gradient

摘要：

利用原位光学显微镜和计算模拟技术研究了材料生长界面微观浓度场对材料结构演化的影响。在电沉积法制备银颗粒中，通过调控电位在电解液中生成氧化银胶体粒子。在外加电场作用下胶体粒子在溶液中运动，进而带动溶质的定向迁移；通过外加电场控制胶体粒子迁移速度，调控生长界面溶质浓度分布。随胶体粒子迁移速度增加，界面传质增强，颗粒生长前沿扩散层变薄，浓度梯度变大，银颗粒形貌由球状纳米晶变为对称枝晶结构，生长速度由10 μm²/s 增大到60 μm²/s。最后结合格子Boltzmann模拟结果，验证了界面浓度场对银颗粒形貌演化的调控作用。

关键词: 微观浓度场, 银颗粒, 原位研究, 动态生长, 形貌演化, 浓度梯度

CLC Number:

TQ 151.5

Yonghui XU, Daoliang CHEN, Dongke SUN, Jinbing LI, Yongsheng HAN. Role of micro-concentration field on morphology of silver particles[J]. CIESC Journal, 2020, 71(S2): 281-288.

胥永辉, 陈道梁, 孙东科, 李金兵, 韩永生. 微观浓度场对银生长形貌的调控作用[J]. 化工学报, 2020, 71(S2): 281-288.

Figures/Tables 8

Fig.1 Experimental setup for in-situ observation of silver particles growth (a) and direction of colloidal particle transmission (b)

Table 1 Physical parameters

参数	符号	数值
初始溶质浓度	c₀	3%
溶质分配系数	k_p	0.17
液相线斜率	m_L	-2.6 K/%(质量)
Gibbs-汤姆逊系数	Γ₀	2.36^-7 mK
液态扩散系数	D_L	3.0^-9 m²/s
固态扩散系数	D_s	3.0^-12
流体运动黏度	ν	5.65657^-7 m²/s
界面动力学各向异性	ε	0.30 m²/s
运动学系数	μ_k,0	2.0^-3 m/(K·s)

Fig.2 An illustration of solute micro-concentration field regulated by colloidal particles (a)， colloidal particles at the cathode front during reaction (b)， XRD pattern and SEM image of colloidal particles (c)

Fig.3 Migration velocity of colloidal particles regulated by electric field intensity

Fig.4 Morphology and growth velocity of silver particles after solute micro-concentration field being regulated

Fig.5 Growth velocity of three morphologies of silver particles

Fig.6 Regulation mechanism of solute micro-concentration field on silver particle morphology

Fig.7 Variation of diffusion layer and concentration gradient at grain tip with flow velocity obtained by lattice Boltzmann simulation(a), visualization of diffusion layer at u = 0.0001 (b) and u = 0.1 (c)

References 31

1	Wiley B, Chen Y, McLellan J, et al. Synthesis and optical properties of silver nanobars and nanorice [J]. Nano Letters, 2007, 7(4): 1032-1036.
2	Nikonorova N A, Barmatov E B, Pebalk D A, et al. Electrical properties of nanocomposites based on comb-shaped nematic polymer and silver nanoparticles [J]. Journal of Physical Chemistry C, 2007, 111(24): 8451-8458.
3	Kamal T, Ahmad I, Khan S, et al. Synthesis and catalytic properties of silver nanoparticles supported on porous cellulose acetate sheets and wet-spun fibers [J]. Carbohydrate Polymers, 2016, 157: 294-302.
4	Prabhu S, Poulose E K. Silver nanoparticles: mechanism of antimicrobial action, synthesis, medical applications, and toxicity effects [J]. International Nano Letters, 2012, 2(1): 32.
5	Kwon S G, Hyeon T. Colloidal chemical synthesis and formation kinetics of uniformly sized nanocrystals of metals, oxides, and chalcogenides [J]. Accounts of Chemical Research, 2008, 41(12): 696-709.
6	Wang Y W, He J T, Liu C C, et al. Thermodynamics versus kinetics in nano-synthesis [J]. Angewandte Chemie International Edition, 2015, 54(7): 2022-2051.
7	Liu W, Yang T, Liu J M, et al. Controllable synthesis of silver dendrites via an interplay of chemical diffusion and reaction [J]. Industrial & Engineering Chemistry Research, 2016, 55(30): 8319-8326.
8	Xiong Y J. Morphological changes in Ag nanocrystals triggered by citrate photoreduction and governed by oxidative etching [J]. Chemical Communications, 2011, 47(5): 1580-1582.
9	Park J E, Kim S, Son J, et al. Highly controlled synthesis and super-radiant photoluminescence of plasmonic cube-in-cube nanoparticles [J]. Nano Letters, 2016, 16(12): 7962-7967.
10	Logaranjan K, Raiza A J, Gopinath S C B, et al. Shape- and size- controlled synthesis of silver nanoparticles using Aloe vera plant extract and their antimicrobial activity [J]. Nanoscale Research Letters, 2016, 11(1): 520-529.
11	Kabashin A V, Delaporte P, Pereira A, et al. Nanofabrication with pulsed lasers [J]. Nanoscale Research Letters, 2010, 5(3): 454-463.
12	Wang H, Han Y S. Shaping particles via controlling the diffusion of building blocks [J]. Industrial & Engineering Chemistry Research, 2015, 54(40): 9742-9749.
13	Ma J Q, Li Z, Lin Q, et al. Diffusion controlling porphyrin assembled structures [J]. Chemical Engineering Journal, 2016, 283: 1051-1058.
14	Wang H, Han Y S, Li J H. Dominant role of compromise between diffusion and reaction in the formation of snow-shaped vaterite [J]. Crystal Growth & Design, 2013, 13(5): 1820-1825.
15	Yang T, Liu J, Dai J H, et al. Shaping particles by chemical diffusion and reaction [J]. CrystEngComm, 2016, 19: 72-79.
16	Yang T, Han Y S. Quantitatively relating diffusion and reaction for shaping particles [J]. Crystal Growth & Design, 2016, 16: 2850-2859.
17	Gradl J, Peukert W. Characterization of micro mixing for precipitation of nanoparticles in a T-mixer [M]// Bockhorn H, Mewes D, Peukert W, et al. Micro and Macro Mixing. Berlin, Heidelberg: Springer, 2010: 105-124.
18	Metthias L, Kind M. Influence of mixing on particle formation of fast precipitation reactions - a new coarse graining method using CFD calculations as a “measuring”instrument [J]. Chemical Engineering Research & Design, 2016, 108: 176-185.
19	Bourne J R. Mixing and the selectivity of chemical reactions [J]. Organic Process Research & Development, 2003, 7(4): 791-797.
20	Sun D K, Wang Y, Yu H Y, et al. A lattice Boltzmann study on dendritic growth of a binary alloy in the presence of melt convection [J]. International Journal of Heat and Mass, 2018, 123: 213-226.
21	Sun D K, Pan S Y, Han Q Y, et al. Numerical simulation of dendritic growth in directional solidification of binary alloys using a lattice Boltzmann scheme [J]. International Journal of Heat & Mass Transfer, 2016, 103: 821-831.
22	Yang T, Han Y S, Li J H. Manipulating dendritic structures via diffusion and reaction [J]. Chemical Engineering Science, 2015, 138: 457-464.
23	Liu W, Yang T, Liu J M, et al. Controllable synthesis of silver dendrites via an interplay of chemical diffusion and reaction [J]. Industrial & Engineering Chemistry Research, 2016, 55(30): 8319-8326.
24	Chen Y, Wang H M. Growth morphologies and mechanism of TiC in the laser surface alloyed coating on the substrate of TiAl intermetallics [J]. Journal of Alloys and Compounds, 2003, 351(1/2): 304-308.
25	Yang T, Doris S, Thaseem T, et al. The effect of mixing on silver particle morphology in flow synthesis [J]. Chemical Engineering Science, 2018, 192: 254-263.
26	Sekerka R F. A stability function for explicit evaluation of the mullins-ekerka interface stability criterion [J]. Journal of Applied Physics, 1965, 36(1): 264-268.
27	Avizienis A V, Martin-Olmos C, Sillin H O, et al. Morphological transitions from dendrites to nanowires in the electroless deposition of silver [J]. Crystal Growth & Design, 2013, 13(2): 465-469.
28	Hurle D T. Interface stability during the solidification of a stirred binary-alloy melt [J]. Journal of Crystal Growth, 1969, 5(3): 162-166.
29	Qian Y H, Humières D, Lallemand P. Diffusion simulation with a deterministic one-dimensional lattice-gas model [J]. Journal of Statistical Physics, 1992, 68(3): 563-573.
30	Humieres R. Multiple-relaxation-time lattice Boltzmann models in three dimensions [J]. Phil. Trans. R. Soc., 2002, 360(1972): 437–451.
31	Sun D K, Xing H, Dong X L, et al. An anisotropic lattice Boltzmann-phase field scheme for numerical simulations of dendritic growth with melt convection [J]. International Journal of Heat and Mass Transfer, 2019, 133: 1240-1250.

[1]	Shiming XU, Zhiqiang LIU, Xi WU, Youwen ZHANG, Junyong HU, Debing WU, Qiang LENG, Dongxu JIN, Ping WANG. Experimental study on the hydrogen production with RED reactor powered by concentration gradient energy [J]. CIESC Journal, 2020, 71(5): 2283-2291.
[2]	ZHANG Fei, WANG Jiabing, YOU Xingwang, LIU Wei, YANG Kun. Stability analysis of natural convection in porous channel with heat generation [J]. , 2015, 66(S1): 146-153.