Se molarity tuned composition and configuration of Ni3Se2/NiSe core-shell nanowire heterostructures for hydrogen evolution reaction

NiSe/Ni3Se2 on nickel foam as an ultra-high-rate HER electrocatalyst: common anion heterostructure with built-in electric field and efficient interfacial charge transfer

“…1e-g) of NiSe/Ni 3 Se 2 @NF shows two distinct lattice structures, i.e., the broader lattice fringe spaces of 0.28 and 0.31 nm correspond to the (012) and (110) planes of hexagonal Ni 3 Se 2 , while the narrower lattice fringe spaces of 0.20 and 0.267 nm correspond to the (102) and (021) planes of hexagonal NiSe. 6,7 The HR-TEM images also reveal that Ni 3 Se 2 is the dominant and skeleton phase with NiSe located at the edge of the nanorods, i.e., Ni 3 Se 2 nanorods wrapped by a thin NiSe layer. The HR-TEM elemental mapping (Fig.…”

“…2c). 7 Based on the above morphological and spectroscopic results, the growth and formation mechanisms of different nickel selenide coatings are proposed as follows. At the beginning of the reaction, N 2 H 4 $H 2 O assists the dissolution of Se powder to produce H + and Se 2À (eqn (1)).…”

“…At elevated hydrothermal temperature of 200 C, Ni 2+ can be reduced by hydrazine hydrate to reactive Nic atoms (eqn (4)) upon heating, which further reacts with NiSe to form Ni 3 Se 2 (eqn (5)) under hydrothermal conditions. 7,12 At a low dosage of Se powder, pure Ni 3 Se 2 coating on nickel foam is formed, i.e., Ni 3 Se 2 @NF. At higher Se dosage, NiSe continues to form on the surface of Ni 3 Se 2 , leading to the formation of heterostructured NiSe/Ni 3 Se 2 @NF.…”

Sulfidation and selenidation of nickel nanoparticles

“…The overpotential of these NPs for the HER is comparable with those reported for other sulfide and selenide NPs. [55][56][57] The electrocatalytic performance cannot be assigned to a specific phase or feature of the NPs, because the samples have mixed phases, and the surfaces and defects in these NPs have not been characterized. The ability of these NPs to catalyze the HER raises a question about the fate and potential role of the ligands coating NPs in the electrochemical environment.…”

Facile Synthesis of Cobalt Oxide as an Efficient Electrocatalyst for Hydrogen Evolution Reaction

“…Because of their Pt-like catalytic behaviors for HER, well electrocatalysts originated from the most abundant elements (Co, Fe, Mo, Ni, Ti, W, and so on) has experienced rapid development over the past decade (Jung et al, 2014;Kuznetsov et al, 2019;Liu et al, 2020). Scientists design and develop various catalysts including transition metal oxides (CoO, Fe 3 O 4 , MoO 2 , TiO 2 , WO 2 ) (Park and Kolpak, 2019;Protsenko et al, 2019;Qian et al, 2019;Li L. et al, 2020;Li S. et al, 2020), metal sulfides (CoS, CuS, FeS 2 , MoS 2 , NiS 2 , V 3 S 4 , WS 2 ) (Li et al, 2018;Shi et al, 2019;Singh et al, 2019;Cao et al, 2020;Hao et al, 2020;Thangasamy et al, 2020), metal carbides (MoC 2 , WC) (Ji et al, 2018;Hussain et al, 2019), metal phosphides (CoP, NiP, FeP, WP, MoP) (Ojha et al, 2017;Zhang C. et al, 2018;Wang P. et al, 2019;Ji et al, 2020;Lin et al, 2020), metal selenides (CoSe 2 , MoSe 2 , NiSe 2 , WSe 2 ) (Wang et al, 2012(Wang et al, , 2020Chen et al, 2020;Nam et al, 2020) and metal boron (Huang et al, 2019;.…”