Boosting alkaline hydrogen evolution reaction kinetics by a local electric field created by polarization of CeO2(100)

作者：Huang, Zanling; Pi, Yuancheng; Tan, Zicong; Peng, Yung-Kang; Zhang, Xuming; Jian, Jing-Xin; Chu, Paul K.; Tong, Qing-Xiao^*; Hu, Liangsheng^*

来源：International Journal of Hydrogen Energy, 2024, 49: 75-86.

DOI：10.1016/j.ijhydene.2023.06.320

• Hydrogen evolution reaction
• Local electric field
• Acid-like local environment
• Polar surface
• Ceria

In this study, a simple and versatile strategy is demonstrated to create acid-like local en-vironments (ALLE) to boost alkaline hydrogen evolution reaction (HER) kinetics of Pt/C, Pt/ CoS2, and other electrocatalysts by introducing a local electric field (LEF) stemming from the polar-faceted cubic CeO2 (C-CeO2). The surface polarity of the C-CeO2 facets is confirmed by trimethylphosphine oxide -31P nuclear magnetic resonance. Operando Raman scattering provides evidence that H3O+ intermediates produce the ALLE. This ALLE shows great enhancement in alkaline HER with activities of the C-CeO2 modified Pt/C and Pt/CoS2 promoted by 2.5 and 5.5 times compared to the counterparts, respectively. The LEF changes the mechanism from slow Volmer-Heyrovsky to fast Volmer-Tafel process. As a result, Pt/ CoS2 + C-CeO2 shows a small Tafel slop of 23.8 mV dec-1 and low overpotentials of 20 and 59 mV at current densities of 10 and 100 mA cm-2, respectively. Importantly, the LEF produces similar effects in other electrocatalysts.

• 单位
  汕头大学