Yan Shenglin, Chen Chengzhen, Zhang Fanghua, Mahyoub Samah A, Cheng Zhenmin
State Key Laboratory of Chemical Engineering, School of Chemical Engineering, East China University of Science and Technology, Shanghai 200237, People's Republic of China.
Nanotechnology. 2021 Apr 16;32(16):165705. doi: 10.1088/1361-6528/abd6af.
To increase the specific surface area, high-density (i.e. number per unit area) Ag nanosheets (ANS) with large electrochemically active surface area and rich edge active sites over Ag plates were synthesized via a facile electrodeposition approach in a double electrode system at a constant current of -1 mA for 1800 s. By adjusting the concentration of HBO (0.5 M, 0.1 M and 0.05 M), which is used to control the growth direction of ANS, ANS-20, -50, -350 were obtained with varying thickness of 20 nm, 50 nm, and 350 nm, respectively. Notably, ANS-20 showed a remarkable current density of -6.48 mA cm at -0.9 V versus the reversible hydrogen electrode (RHE), which is almost 1.6 and 2.4 times as high as those of ANS-50 and -350, respectively. Furthermore, ANS-20 exhibits the best CO selectivity of 91.2% at -0.8 V versus RHE, while the other two give 84.6% and 77.9% at the same potential. The excellent performance of ANS-20 is attributed to its rich edge active sites and large electrochemically active surface area (ECSA).
为了增加比表面积，通过在双电极系统中以-1 mA的恒定电流进行1800 s的简便电沉积方法，在银板上合成了具有大电化学活性表面积和丰富边缘活性位点的高密度（即单位面积数量）银纳米片（ANS）。通过调节用于控制ANS生长方向的HBO浓度（0.5 M、0.1 M和0.05 M），分别获得了厚度为20 nm、50 nm和350 nm的ANS-20、ANS-50、ANS-350。值得注意的是，相对于可逆氢电极（RHE），ANS-20在-0.9 V时显示出-6.48 mA cm的显著电流密度，分别几乎是ANS-50和ANS-350的1.6倍和2.4倍。此外，相对于RHE，ANS-20在-0.8 V时表现出最佳的CO选择性，为91.2%，而其他两种在相同电位下的选择性分别为84.6%和77.9%。ANS-20的优异性能归因于其丰富的边缘活性位点和大的电化学活性表面积（ECSA）。
