Polycrystalline CoP/CoP₂ Structures for Efficient Full Water Splitting

Abstract

Transition-metal phosphides (TMPs) have attracted extensive attention for use in the field of full water splitting. Various methods have been investigated to obtain high catalytic activity, but in these synthetic processes other active materials are inevitably introduced to modify or load onto the surface of the TMP to further improve the catalytic performance. Herein, we describe a novel approach for preparing CoP/CoP 2 structures (650 8C) by pyrolysis of a complex formed from Co ions crosslinked with phytic acid (PA) using 2-methylimidazole (MeIM). The integration of CoP 2 and CoP in the structures can enhance the intrinsic electrical conductivity, and facilitate electron transfer from solution to the electrode. Overpotentials of only 250 and 239 mV were required to support the current densities of 10 and 20 mA cm À2 for the oxygen evolution reaction and hydrogen evolution reaction, respectively, demonstrating the potential of the novel material for practical overall water splitting.[a] S.

DFT Study on the Hydrogen Evolution Reaction for Different Facets of Co2P

“…Although lots of experiments have been done about Co 2 P, the facet‐dependent HER activity of Co 2 P has not been systemically studied experimentally or theoretically, which is important to understand the facet effects on HER activity for Co 2 P. In this paper, DFT calculations for different adsorption sites on several facets of Co 2 P have been performed to investigate the facet‐dependent HER activity of Co 2 P. Beyond that, multiple linear regression has been applied to quantitatively analyze the relationship between the local structures and the corresponding Gibbs free energy of H* (ΔG H* ). The mathematical model of multiple linear regression is helpful in understanding the facet impact on HER activity and finding out the facet with best HER activity.…”

“…In particular, the transition metal phosphides (TMPs) have been proved to have both high stability and high activity like MoP,, FeP/FeP 2 ,, CoP/Co 2 P, and Ni 2 P ,. Among numerous TMPs developed, the Co−P compounds, which are non‐noble metal catalysts, have attracted extensive interest in the field of HER catalysis in the past years, owing to their good performance, such as high activity,, outstanding stability both in acidic electrolytes,, and alkaline solutions,, high conductivity, large‐scaled production and so on. So far, there are two major Co−P components explored experimentally as CoP and Co 2 P. Callejas et al .…”

Tungsten‐Doped CoP Nanoneedle Arrays Grown on Carbon Cloth as Efficient Bifunctional Electrocatalysts for Overall Water Splitting

“…The fine XPS peaks of Co 2p 3/2 at 778.5, 782.4 and 786.8 eV observed from WÀ CoP/CC can be attributed to the CoÀ P, CoÀ O and the satellite peak, respectively ( Figure 2b). [24] Compared to the P 2p spectra of CoP/CC, the binding energy of CoÀ P in WÀ CoP/CC shifted negatively by~0.2 eV also suggest- 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 ing that W weakens the CoÀ P bind. The two peaks at 129.8 and 130.7 eV are attributed to the P 2p 1/2 and P 2p 3/2 of CoÀ P and the other two peaks at 129.6 and 130.5 eV are related to WÀ P. The broad peak at 134 eV arises from PÀ O due to surface oxidation.…”

Mo‐Doped Ni3S2 Nanowires as High‐Performance Electrocatalysts for Overall Water Splitting

“…With the rapid growth of energy consumption and associated environmental issues, developing clean and renewable energy is highly desirable . Hydrogen, producing H 2 O as the only by‐product, has been considered as the ideal candidate for the replacement of fossil fuels in the future due to the zero emission of greenhouse gas during its utilization .…”