Interface Engineering of Partially Phosphidated Co@Co–P@NPCNTs for Highly Enhanced Electrochemical Overall Water Splitting

Abstract

Interface engineering is promising but still challenging for developing highly efficient and stable non‐noble‐metal‐based electrocatalysts for water splitting. Herein, partially phosphidated core@shell Co@Co–P nanoparticles encapsulated in bamboo‐like N, P co‐doped carbon nanotubes (denoted as Part‐Ph Co@Co–P@NPCNTs) are prepared through a pyrolysis–oxidation–phosphidation strategy. In this structure, each Co nanoparticle is covered with a thin Co–P layer to form a special core@shell heterojunction interface, and the core@shell structure is further encapsulated by N, P co‐doped CNTs that not only protect the Co from corrosion but also guarantee an effective and fast electron transfer on cobalt phosphide. As a bifunctional catalyst for both the hydrogen evolution reaction and oxygen evolution reaction, it exhibits an excellent activity for overall water splitting, and enables long‐term operation without significant degradation. Density functional theory calculations demonstrate that the interface of the Co/Co2P heterojunction could lower the values of ΔGH* (hydrogen adsorption) and ΔGB (water dissociation), which are negatively correlated to the j10, because of the electronic structures of up‐shifted d‐band center. This study not only presents an efficient and stable electrocatalyst for overall water splitting but also provides a special route for the interface engineering of heterostructures.

Sub‐Thick Electrodes with Enhanced Transport Kinetics via In Situ Epitaxial Heterogeneous Interfaces for High Areal‐Capacity Lithium Ion Batteries

“…However, the Raman peaks of Ni 2 P cannot be detected, [35,36] which were perpetual to Ni 2 P. Noticeably, the Raman vibration of NiO cannot be observed in the Raman spectrum of NF-CNNOP sample but its intensity significantly decreases, suggesting the partial phosphidation of the ternary hybrid sample. [37,38] The cross-sectional morphological studies on the pristine NF and as-prepared samples are presented in Figure 1c-f to have detailed understanding of the surface morphological reaction. The pristine NF itself had an internal thickness of 3.20 µm.…”

Doping Ruthenium into Metal Matrix for Promoted pH‐Universal Hydrogen Evolution

“…As the Ru content increases, the peak positions for Co 5 Ru 1 @NCNT/PF shift smoothly from hexagonal phases Co (PDF# 05-0727) to Ru (PDF# 06-0663). [3,30] Obviously, no Ru diffraction peaks can be found in XRD patterns of Co 5 Ru 1 @NCNT/PF, suggesting that the Ru atoms are incorporated into the Co lattice in the sample. [30][31][32] The morphology and size of as-synthesized samples are shown in Figure 1b-d.…”

Electrocatalysis in confined spaces: interplay between well-defined materials and the microenvironment

“…68 Unfortunately, the development of efficient bifunctional electrocatalysts to simultaneously promote HER and OER in the same electrolyte remains challenging. 69,70 Wang et al reported a bifunctional catalyst for HER and OER with Co NPs encapsulated in nitrogen-doped carbon (Co@N-C) which was prepared by pyrolysis of cobalt acetate and imidazole followed by acid leaching. 71 The unique encapsulation structure in Co@N-C leads to high activity and stability for HER in a wide pH range.…”