硫掺杂对氢氧化钴析氢性能的影响

Effect of Sulfur Doping on Hydrogen Evolution Performance of Cobalt Hydroxide

本文通过电沉积的方法在碳布表面生长了硫掺杂氢氧化钴(S-Co(OH)_(2)/CC)。研究表明:S的引入,使Co(OH)_(2)的部分晶态结构转变为高活性的非晶态结构,且增加了电化学活性面积,进而提高了Co(OH)_(2)在碱性条件下的电催化析氢性能,达到10mA·cm^(-2)电流密度时所需过电位较Co(OH)_(2)降低近80 mV,当电流密度大于90 mA·cm^(-2)时,催化活性优于商业Pt/C,经过3000圈的CV循环,催化活性未衰减。然而由于其结晶度下降,使电子转移速率变慢,动力学性能变差,表现出增大的电荷转移阻抗和Tafel斜率。

In this work,sulfur doped cobalt hydroxide(S-Co(OH)_(2)/CC)is grown on the surface of carbon cloth by electrodeposition.With the introduction of S,the partial crystalline structure of Co(OH)_(2)is transformed into an amorphous structure with high activity,and the electrochemical active area is increased,which improves the electrocatalytic hydrogen evolution performance of Co(OH)_(2)under alkaline conditions.When the current density reaches 10 mA cm^(-2),the required overpotential is reduced by nearly 80 mV compared with Co(OH)_(2).When the current density is greater than 90 mA cm^(-2),the catalytic activity is superior to that of commercial Pt/C.After 3000 CV cycles,the catalytic activity do not attenuate.However,due to the decrease of crystallinity,the electron transfer rate slows down and the kinetic performance deteriorates,showing an increased charge transfer impedance and Tafel slope.