Anhui Normal University

About: Anhui Normal University is a education organization based out in Wuhu, China. It is known for research contribution in the topics: Catalysis & Population. The organization has 7955 authors who have published 7309 publications receiving 117443 citations.

Construction of multi-dimensional core/shell Ni/NiCoP nano-heterojunction for efficient electrocatalytic water splitting

Abstract: Tuning structure, morphology and electronic state of electrocatalysts is essential to achieve highly efficient water splitting. Herein, we report synthesis of snap bean-like multi-dimensional core/shell Ni/NiCoP nano-heterojunctions (NHs) by adopting a solid phase transformation strategy. In the special structure, Ni nanoparticles are enclosed and strung by single phased NiCoP, forming strings of Ni/NiCoP core/shell heterojunctions, which showed improved stability and activity for both hydrogen evolution (HER) and oxygen evolution reactions (OER). X-ray photoelectron spectroscopy and synchrotron-radiation-based X-ray absorption spectroscopy reveal that interactions at the interface of Ni/NiCoP greatly changed electronic structures, which is a key intrinsic factor to underpin the enhanced electrocatalytic performance. Density functional theory calculations demonstrate Ni/NiCoP interface provide more optimal binding strength for H adatom and H2O molecule for HER, strong capture of hydroxyl, high valence Ni/Co species for OER. All these peculiarities facilitate the electrocatalytic process: only 1.57 V was needed to reach the current density of 10 mA·cm−2 for the overall water splitting using Ni/NiCoP NHs as both electrodes. This work demonstrates a facile strategy for synthesis of sophisticated catalytic interface at nano level and endows nano-heterojunction catalysts with enhanced performance for catalytic applications.

Porphyrin-like Fe-N 4 sites with sulfur adjustment on hierarchical porous carbon for different rate-determining steps in oxygen reduction reaction

Abstract: We developed a strategy based on coordination polymer to synthesize singleatom site Fe/N and S-codoped hierarchical porous carbon (Fe1/N,S-PC). The as-obtained Fe1/N,S-PC exhibited superior oxygen reduction reaction (ORR) performance with a half-wave potential (E1/2, 0.904 V vs. RHE) that was better than that of commercial Pt/C (E1/2, 0.86 V vs. RHE), single-atom site Fe/N-doped hierarchical porous carbon (Fe1/N-PC) without S-doped (E1/2, 0.85 V vs. RHE), and many other nonprecious metal catalysts in alkaline medium. Moreover, the Fe1/N,S-PC revealed high methanol tolerance and firm stability. The excellent electrocatalytic activity of Fe1/N,S-PC is attributed to the synergistic effects from the atomically dispersed porphyrin-like Fe-N4 active sites, the heteroatom codoping (N and S), and the hierarchical porous structure in the carbon materials. The calculation based on density functional theory further indicates that the catalytic performance of Fe1/N,S-PC is better than that of Fe1/N-PC owing to the sulfur doping that yielded different rate-determining steps.