Rational Regulation of Crystalline/Amorphous Microprisms‐Nanochannels Based on Molecular Sieve (VSB‐5) for Electrochemical Overall Water Splitting

Abstract

Rational regulation of the composition and structure of electrocatalysts is crucial to the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). Herein, a new electrocatalyst of nickel phosphate microprism (VSB/NiPO) is developed via a simple solvothermal reaction. The microprism is mainly composed of Versailles‐Santa Barbara‐5 (VSB‐5, molecular sieve) with unique nanochannels, which contribute to accelerating mass transfer and exposing more active sites, thus displaying excellent HER activity. Subsequently, the crystallinity and electronic structure of the framework are modulated by incorporating Fe with the combination of calcination and impregnation. The nanochannels are converted to the amorphous arrangement, and the Ni centers are regulated to the higher valence. The resultant Fe‐VSB/NiPO‐500 exhibits a low OER overpotential of 227 mV at 50 mA cm−2. Interestingly, an integrated electrolyzer assembled by VSB/NiPO(−) and Fe‐VSB/NiPO‐500(+) performs well for overall water splitting, which requires only 1.487 V to achieve 10 mA cm−2, and remains stable at 100 mA cm−2 over 100 h. This finding opens a new avenue for developing VSB‐5 in the field of electrocatalysis.

Hollow Mo-doped NiSx nanoarrays decorated with NiFe layered double-hydroxides for efficient and stable overall water splitting

“…This characteristic can be attributed to the special hollow core–shell structure that improves the solvent wettability, and thus in turn favors the exposure of more –OH groups to form hydrogen bonds with hydrogen protons in the water. 49 The as-prepared super-hydrophilic electrode facilitates close contact between the electrode and electrolyte, which effectively improves the surface utilization efficiency of the whole reaction process. 50 Likewise, the CA of underwater gas bubbles is measured to be 130.8°, 138.7°, 145.6° and 160.6° for NF, NiMoO 4 · x H 2 O/NF, Mo-NiS x /NF and Mo-NiS x @NiFe LDH/NF, respectively, indicating that the Mo-NiS x @NiFe LDH/NF is more aerophobic than others (Fig.…”

Prelithiated, Multiscale Nickel Phosphate Octahydrate Platelets by a Tailored Nanoarchitectonics Approach

“…The former corresponds to P−P bonds and the latter to phosphates. 18,23,50 The Ni 2p spectrum displays peaks at 855.1 and 872.8 eV correlating to Ni 2p 3/2 and Ni 2p 1/2 , respectively. Each is resolved into two components, Ni 2+ (low BE) and Ni 3+ (high BE), and followed by its satellite peaks.…”

Enabling Internal Electric Fields to Enhance Energy and Environmental Catalysis

“…[ 73 ] With the help of different additives, such as surfactants, catalysts, end‐capping agents, the same structural unit can be converted into different morphologies with different exposed lattice planes, which can achieve controllable lattice matching and exposure. [ 74 ] Interestingly, subsequent pyrolysis of the precursor prepared by wet chemical methods can produce core–shell or island heterostructures accompanied by largely continued heterointerfaces, and the choice of annealing atmosphere, annealing temperature and time can dominate the transformation of the precursor to other materials (e.g., sulfides, phosphides, and carbides, etc.). [ 75 ] Different formation energies drive precursor decomposition into multiple materials, leading to the in situ formation of atomic heterostructures with abundant heterointerfaces.…”