Abstract:
The selective electrocatalytic reduction of nitrobenzene (NB) to aniline demands a desirable cathodic catalyst to overcome the challenges of the competing hydrogen evolution reaction (HER), a higher overpotential, and a lower selectivity. Here, we deposit Co-doped 1T MoS2 on Ti mesh by the solvothermal method with different doping percentages of Co as x % Co-MoS2 (where x = 3, 5, 8, 10, and 12%). Because of the lowest overpotential, lower charge-transfer resistance, strong suppression of the competing HER, and higher electrochemical surface area, 8% Co-MoS2 achieves 94% selectivity of aniline with 54% faradaic efficiency. The reduction process follows first-order dynamics with a reaction coefficient of 0.5 h-1. Besides, 8% Co-MoS2 is highly stable and retains 81% selectivity even after 8 cycles. Mechanistic studies showed that the selective and exothermic adsorption of the nitro group at x % Co-MoS2 leads to a higher rate of NB reduction and higher selectivity of aniline. The aniline product is successfully removed from the solution by polymerization at FTO. This study signifies the impact of doping metal atoms in tuning the electronic arrangement of 1T-MoS2 for the facilitation of organic transformations.
摘要:
硝基苯(NB)选择性电催化还原为苯胺需要理想的阴极催化剂来克服竞争析氢反应(HER)的挑战,更高的过电位,和较低的选择性。这里,我们通过溶剂热法将Co掺杂的1TMoS2沉积在Ti网上,其中Co的掺杂百分比不同,为x%Co-MoS2(其中x=3、5、8、10和12%)。因为最低的过电位,较低的电荷转移电阻,强烈压制她的竞争对手,和更高的电化学表面积,8%Co-MoS2实现了94%的苯胺选择性和54%的法拉第效率。还原过程遵循一级动力学,反应系数为0.5h-1。此外,8%Co-MoS2是高度稳定的并且即使在8个循环之后仍保持81%的选择性。机理研究表明,硝基在x%Co-MoS2下的选择性和放热吸附导致更高的NB还原速率和更高的苯胺选择性。通过在FTO下聚合,成功地从溶液中除去苯胺产物。这项研究表明掺杂金属原子对调节1T-MoS2的电子排列以促进有机转化的影响。