Fabrication of Hollow CoP/TiO_x Heterostructures for Enhanced Oxygen Evolution Reaction

Abstract

Transition‐metal phosphides have flourished as promising candidates for oxygen evolution reaction (OER) electrocatalysts. Herein, it is demonstrated that the electrocatalytic OER performance of CoP can be greatly improved by constructing a hybrid CoP/TiOx heterostructure. The CoP/TiOx heterostructure is fabricated using metal–organic framework nanocrystals as templates, which leads to unique hollow structures and uniformly distributed CoP nanoparticles on TiOx. The strong interactions between CoP and TiOx in the CoP/TiOx heterostructure and the conductive nature of TiOx with Ti3+ sites endow the CoP–TiOx hybrid material with high OER activity comparable to the state‐of‐the‐art IrO2 or RuO2 OER electrocatalysts. In combination with theoretical calculations, this work reveals that the formation of CoP/TiOx heterostructure can generate a pathway for facile electron transport and optimize the water adsorption energy, thus promoting the OER electrocatalysis.

Highly Efficient Oxygen Reduction Reaction Activity of N‐Doped Carbon–Cobalt Boride Heterointerfaces

“…The charge density difference plot further suggests that the heterointerface formation leads to a substantial charge redistribution at the interface and graphene (Figure 5e), affecting the adsorptions of reactant molecules and boosting the reaction kinetics. [47,48] Figure 5f shows the density of states of CoB, N-doped carbon, and CoB-N x heterointerface structures. The CoB-N x heterointerface has abundant density of states (DOS) near the Fermi level, implying an enhanced electric conductivity.…”

Constructed Interfacial Oxygen‐Bridge Chemical Bonding in Core‐Shell Transition Metal Phosphides/Carbon Hybrid Boosting Oxygen Evolution Reaction

“…For example, the synergistic effect between two components is capable of optimizing the electronic structure of active sites, and the adjusted adsorption energy of water can lead to greatly promoted reaction kinetics to further accelerate the reaction rates. [23] Heterostructure construction and interface engineering are deemed as effective way to take advantage of the synergistic effect between the components, such as constructing covalent metalÀ OÀ C bonds. Xue and co-workers proposed that the CoÀ OÀ C bond between transition metal oxides and carbon played a critical role in improving the OER activity by introducing an extra reaction step in deprotonation of HO*.…”

Structural dependence of electrosynthesized cobalt phosphide/black phosphorus pre-catalyst for oxygen evolution in alkaline media

“…Furthermore, the synergistic effect between the CoP and its oxidized species promotes the OER kinetics. 13 As a case study, the XPS spectra and TEM image of the CoP/ BP-30 heterojunction after activation were obtained (named as CoP/BP-30R). In the high-resolution XPS spectra for Co 2p, P 2p, and O 1s (Fig.…”

“…Unfortunately, their scarcity and high cost hinder their production on a large scale as well as their practical applications. 13 Science and industry would greatly benefit if alternative OER electrocatalysts could be synthesized and if expensive noble catalysts could be replaced.…”