Zheng Yang, Xu Xinxin
Department of Chemistry, College of Science, Northeastern University, Shenyang 110819, China.
Institute for Frontier Technologies of Low-Carbon Steelmaking, Northeastern University, Shenyang 110819, China.
ACS Appl Mater Interfaces. 2020 Dec 2;12(48):53739-53748. doi: 10.1021/acsami.0c14431. Epub 2020 Nov 17.
The electrocatalytic hydrogen evolution reaction is an ideal method for H production. To improve the performance of polyoxometalate-based electrocatalyst in the hydrogen evolution reaction, one O in polyoxometalate is replaced by S. This weakens the binding of polyoxometalate to H*, facilitates its desorption, and improves the H generation property. Vulcanized polyoxometalate only requires 55 mV to achieve 10 mA·cm current in the hydrogen evolution reaction. This electrocatalyst also exhibits promising performance in phenol degradation reaction, which is an ideal substitute for high-energy-consuming oxygen evolution reaction in H production due to low voltage to drive. To acquire 100 and 200 mA·cm in the phenol degradation reaction, this vulcanized polyoxometalate only consumes 1.38 and 1.41 V. With this electrocatalyst working as a cathode and an anode simultaneously, an electrolyzer is constructed by employing phenol-containing KOH as an electrolyte. To obtain 100 and 200 mA·cm current, the electrolyzer only requires 1.54 and 1.57 V. Because energy-efficient phenol degradation reaction occurs, these values are obviously lower than the oxygen evolution reaction involved in the overall water-splitting H production. This work provides a universal method to enhance the hydrogen evolution reaction (HER) activity of polyoxometalates. Furthermore, a new method is explored, which achieves energy conservation and phenol degradation simultaneously in H production.
电催化析氢反应是一种理想的制氢方法。为了提高基于多金属氧酸盐的电催化剂在析氢反应中的性能，将多金属氧酸盐中的一个氧原子用硫原子取代。这削弱了多金属氧酸盐与H*的结合，促进了其脱附，并改善了产氢性能。硫化多金属氧酸盐在析氢反应中仅需55 mV即可达到10 mA·cm²的电流。这种电催化剂在苯酚降解反应中也表现出良好的性能，由于驱动电压低，它是制氢中高能耗析氧反应的理想替代品。在苯酚降解反应中要达到100和200 mA·cm²的电流，这种硫化多金属氧酸盐仅消耗1.38和1.41 V的电压。以这种电催化剂同时作为阴极和阳极，采用含苯酚的KOH作为电解质构建了一个电解槽。要获得100和200 mA·cm²的电流，该电解槽仅需1.54和1.57 V的电压。由于发生了节能的苯酚降解反应，这些值明显低于全水解制氢中涉及的析氧反应。这项工作提供了一种提高多金属氧酸盐析氢反应（HER）活性的通用方法。此外，还探索了一种新方法，该方法在制氢过程中同时实现了节能和苯酚降解。
