Hierarchically Self-Supporting Phosphorus-Doped CoMoO₄ Nanoflowers Arrays toward Efficient Hydrogen Evolution Reaction

Abstract

Advances in non-noble-metal electrocatalysts for sustainable hydrogen evolution reactions (HERs) have had a significant impact on the production of renewable clean energy (H 2 ). Benefitting from high-efficiency synthesis methods, a controlled catalyst P-CoMoO 4 @Ni with a hierarchical structure with different morphologies on the surface of nickel foam (NF) has been synthesized. In particular, the optimized nanoflower oxide array electrode P-CoMoO 4 @Ni-1 performed as the best catalyst for HER with a large specific surface area and low charge-transfer resistance and was capable of delivering current densities of 100 and 150 mA cm −2 under low overpotentials of 98 and 162 mV, respectively. In addition, this work demonstrated that catalyst arrays adopted by polyoxometalates (POMs) as precursors with uniform nanoflower structures might be able to improve electrocatalytic performance as well as provide fundamental research of catalyst materials with high efficiency at low potentials in HER.

Construction of Mo-Based p–n Heterojunction with Enhanced Oxidase–Mimic Activity for AOPs and Antibiofouling

“…Compared with pure CoMoO 4 , these peaks shift to a low energy direction obviously, which is also confirmed in CoMoO 4 /MoS 2 , electrons move from MoS 2 to CoMoO 4 . In the high-resolution O 1s spectrum of CoMoO 4 /MoS 2 , the peaks located at 530.8 can be attributed to lattice oxygen (Figure d) . Two peaks appear in the high-resolution S 2p spectrum of CoMoO 4 /MoS 2 (Figure e).…”

Tuning Electrochemical Hydrogen-Evolution Activity of CoMoO4 through Zn Incorporation

“…Recently, there has been a surge of interest in the electrochemical properties of bimetallic oxides in comparison to single-component oxides due to their improved characteristics [11][12][13]. Bimetallic oxide catalysts could alter the electronic structures of the catalysts by regulating the composition, physical, and chemical aspects of the metals in the structure [14,15]. Moreover, bimetallic oxides offer multiple active sites, trap inactive active sites, and elevate the conductivity at the same time [14,16].…”

“…Bimetallic oxide catalysts could alter the electronic structures of the catalysts by regulating the composition, physical, and chemical aspects of the metals in the structure [14,15]. Moreover, bimetallic oxides offer multiple active sites, trap inactive active sites, and elevate the conductivity at the same time [14,16]. TM molybdates, as a subgroup of bimetallic compounds, have received much attention because of their high electrochemical activities, which can be ascribed to their rich polymorphism and high conductivity originating from metal molybdates [12,17].…”

“…Only a few reports have been released that elaborate on the effect of elemental doping on the HER activity of CoMoO 4 , and those which have done so mostly focused on anion doping. Wen et al [14] utilized a phosphorous doping technique to fabricate a controlled catalyst P-CoMoO 4 @Ni with a hierarchical structure with different morphologies on the surface of nickel foam (NF). The best HER performances reported by this group were obtaining current densities of 100 and 150 mA cm −2 under low overpotentials of 98 and 162 mV, respectively.…”

Advances in Interfacial Engineering and Their Role in Heterostructure Formation for HER Applications in Wider pH

“…In this regard, water splitting with the lowest carbon footprint as the most promising method to generate hydrogen has been extensively researched with a rich reserve of electrocatalysts for hydrogen evolution (HER). With the practical use of high cost noble metal Pt as the state of the art catalyst, a pool of non-noble metal catalysts have been explored, yet it still leaves behind unfilled gaps. − A clear understanding of the HER mechanism described in acidic/basic medium will provide education about the challenges and possibilities (Figure ). Briefly, H 2 evolution takes place at the cathode of a water electrolyzer and follows two elementary steps. , …”