Effect of pH on the growth of MoS2 (002) plane and electrocatalytic activity for HER
Effect of pH on the growth of MoS2 (002) plane and electrocatalytic activity for HER
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DOI：
10.1016/j.ijhydene.2015.09.076
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发表时间：
2016-01-05
影响因子：
7.2
通讯作者：
Liu, Chen-Guang
中科院分区：
文献类型：
--
作者：
Hu, Wen-Hui;Han, Guan-Qun;Liu, Chen-Guang
用水热法在不同pH值下合成了不同(002)强度的MoS_2用于析氢反应(HER)。在pH=2~3时得到的MoS_2具有最小的(002)和(100)峰强度比(I(002)/(100))和最大的BET比表面积，这意味着在低pH条件下MoS_2的(002)面生长受到抑制，堆积层减少。由于(002)晶面是HER的惰性晶面，因此低pH(pH=2-3)比高pH更适合增加MoS_2的活性中心。电催化的结果表明，在pH=2-3的条件下合成的MoS_2比pH=7-8或pH=12-13合成的MoS_2具有更小的塔菲尔斜率和更低的电阻。相应的电容性质表明，在pH=2~3时得到的MoS_2具有最高的比电容，这表明在低pH时MoS_2的分散性最好，比表面积最大。因此，pH对控制(002)晶面的生长和改善MoS_2的活性位有重要影响。版权所有(C)2015，氢能源出版有限责任公司。爱思唯尔有限公司出版。保留所有权利。
MoS2 with different (002) intensity have been synthesized for hydrogen evolution reaction (HER) through a facile hydrothermal method at different pH value. MoS2 obtained at pH = 2 -3 exhibits the smallest intensity ratio between (002) and (100) peaks (I ((002)/(100))) and the largest BET surface area, which implying the restrained growth of (002) plane and the decreasing of stacking layers of MoS2 at low pH. Because (002) plane is inert plane for HER, low pH (pH = 2-3) is more suitable for increasing the active sites of MoS2 than high pH. The results of the electrocatalytic HER confirm that MoS2 synthesized at pH = 2-3 has the smaller Tafel slope and the lower resistance than pH = 7-8 or pH = 12-13. The corresponding capacitive properties show similar results that MoS2 obtained at pH = 2-3 has the highest specific capacitance among the different pH, which identified the best dispersion and largest BET surface area of MoS2 at low pH. Therefore, pH has made important impact on the controlling growth of (002) plane and the improved active sites of MoS2. Copyright (C) 2015, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.