142 / 2022-02-03 23:22:56
Controllable preparation and doping modification of two-dimensional tellurium nanosheets as bifunctional electrocatalysts
Te nanosheets, hydrothermal reaction, morphology control, doping modification, electrocatalytic performance
(7)矿物与先进能源材料 > 8. 新型能源材料
摘要录用
广兰 王 / 中国矿业大学
亚波 朱 / 中国矿业大学

ABSTRACT: As an important new energy, the conversion efficiency of hydrogen is a research hotspot today. The electrocatalytic performance of the electrode for hydrogen production has a decisive effect on this efficiency. Two-dimensional tellurium (2D Te) is a newly discovered layered material, which has aroused great interest in the field of electrocatalysis, yet its production remains challenging. Herein, Te nanomaterials were synthesized by hydrothermal reaction. It was found that the morphology of Te crystals could present from nanowire to nanosheet and irregular bulk particle by changing pH value and reaction time when hydrazine as reducing agent. Moreover, their electrocatalytic performance was tested and showed that Te nanosheets had the optimal comprehensive performance. On the basis, the Te nanosheets were doped with transition metal for better performance. The results indicated that the electrocatalytic properties of the samples varied greatly after doping various transition metals. Specifically, doping Co can greatly improve the hydrogen evolution performance, and the optimal sample only needs a hydrogen evolution overpotential of 147mV to reach a current density of 10 mA·cm-2. However, doping Fe can greatly improve the oxygen evolution performance and the oxygen evolution overpotential of the optimal sample is 277mV at 10 mA·cm-2. It was suggested that different transition metals doped into Te nanosheets should produce different functions, resulting in different electrocatalytic performance. Practically, doping Co usually causes optimized adsorption energy to promote hydrogen formation, while doping Fe facilitates the formation of lattice oxygen which promotes oxygen evolution. This influence mechanism is worthy of in-depth exploration. This work provides a promising route to design and optimize layered two-dimensional materials as electrocatalysts.

登录 注册缴费 提交稿件 酒店预订