Atomic‐Level Surface Engineering of Nickel Phosphide Nanoarrays for Efficient Electrocatalytic Water Splitting at Large Current Density

Abstract

The self-supported NiP nanosheet array electrode with enriched P vacancies and atomic-level Co doping is achieved by a controlled cation-exchange strategy excluding complicated chemical reactions and post-treatment steps. Such NiP nanoarray electrode exhibits excellent performance and long-term stability (over 500 h) for electrocatalytic water splitting at large current density, outperforming noble-metal catalysts in electrocatalytic hydrogen evolution reaction and oxygen evolution reaction.

Deep Reconstruction of the NiFeSP Nanosheet Catalyst for Large Current–Density Water Oxidation

“…The SEM images demonstrate that the nanosheet characteristics of the NiFeSP/NF-600 electrode was well preserved with decreased thickness (Figure b,c), and the number of nanosheets increased significantly, which possibly resulted from surface rearrangement of the catalyst during OER. A close contact with the electrolyte is made possible by such a highly open network, which is regarded to be advantageous for mass transfer during electrocatalysis . From the XRD patterns in Figure S13 (Supporting Information), expect for the diffraction peaks of NF (PDF#04-0850), NiFeSP/NF-600 only displays tiny characteristic peaks of FeOOH (PDF#22-0353) due to the poor crystallinity of metal (oxy)­hydroxides.…”

Hydrothermal-Dependent Oxygen Vacancy-Rich NiFe Layered Double Hydroxide/BiVO4 Photoanodes for Stable Solar Water Splitting

“…42 The peak valleys in an atomic intensity profile along the green line further verify the distribution of O vac interrupting the ordered atomic arrangement (Figure 2e). 32,43 The EPR spectrum is also collected and reveals relatively obvious defects in the v-NiFe-LDH/BiVO 4 photoanode around g = 2.00 (Figure 2f), indicating that the NiFe-LDH cocatalyst increases the content of O vac by virtue of O vac engineering.…”

A Facile Molecular Approach to Amorphous Nickel Pnictides and Their Reconstruction to Crystalline Potassium‐Intercalated γ‐NiOOHx Enabling High‐Performance Electrocatalytic Water Oxidation and Selective Oxidation of 5‐Hydroxymethylfurfural

“…[11,12] Nickel pnictides, especially phosphides, have been extensively explored as efficient OER electrocatalysts. [32][33][34] However, the majority of the reported nickel pnictides have been synthesized using high-temperature, energy-intensive, conventional hydrothermal, or solid-state approaches that lead to the formation of large and crystalline particles. [35,36] Therefore, it is crucial to develop novel, energy-efficient, room-temperature synthetic routes toward the controlled formation of especially amorphous nickel pnictide nanomaterials for the OER.…”