The High Electrocatalytic Performance of NiFeSe/CFP for Hydrogen Evolution Reaction Derived from a Prussian Blue Analogue

Abstract

Non-noble-metal-based chalcogenides are promising candidates for hydrogen evolution reaction (HER) by harnessing the architectural design and the synergistic effect between the elements. Herein, a porous bimetallic selenide (NiFeSe) nanocube deposited on carbon fiber paper (NiFeSe/CFP) was synthesized through a facile selenization reaction based on Prussian blue analogues (PBAs) as precursors. The NiFeSe/CFP exhibited excellent HER activity with an overpotential of just 186 mV for a current density of 10 mA cm−2 in 1.0 M KOH at ambient temperature, similar to most of the state-of-the-art transition metal chalcogenides. The corresponding Tafel slope was calculated to be 52 mV dec−1, indicating fast discharge of the proton during the HER. Furthermore, the catalyst could endure long-term catalytic tests and showed remarkable durability. The enhanced electrocatalytic performance of NiFeSe/CFP is attributed to the unique 3D porous configuration inherited from the PBA templates, enhanced charge transfer occurring at the heterogeneous interface due to the synergistic effect between the bimetallic phases, and the high conductivity improved by the formation of amorphous carbon shells during the selenization. These findings prove that the combination of inexpensive metal–organic framework precursors and hybrid metallic compounds is a feasible way to realize the performance enhancement of non-noble-metal-based chalcogenides towards alkaline HER.

Modulating Electronic Structure by Etching Strategy to Construct NiSe2/Ni0.85Se Heterostructure for Urea‐Assisted Hydrogen Evolution Reaction

“…Two sets of well‐defined lattice fringes, which had an intersection angle of about 78.6° and interplanar spacing of 0.267 and 0.267 nm, were assigned to the (01$${{\bar{2}}}$$) and ($${{\bar{2}}}$$10) crystal planes of cubic phase NiSe 2 (JCPDS: 04‐003‐1991). [ 18 ] What is more, the fast Fourier transformation (FFT) pattern in Figure 1d 2 further proved the existence of (01$${{\bar{2}}}$$) and ($${{\bar{2}}}$$10) crystal planes and confirmed the chemical composition and crystal structure of NiSe 2 in the NiSe 2 /Ni 0.85 Se‐2h heterostructure octahedra. In the edge of the NiSe 2 /Ni 0.85 Se‐2h octahedra, the high‐resolution lattice fringes, which exhibited diameters of about 0.150 nm, corresponded to the (201) crystal plane of hexagonal phase Ni 0.85 Se (JCPDS: 00‐018‐0888).…”

“…[ 17 ] Besides, the influence of different reaction times on the preparation of NiSe 2 precursor has been investigated, and the crystal structure and morphology of the obtained samples that underwent 16‐ or 24‐h reactions were almost the same as the sample that underwent 20 h reaction (Figure S2, Supporting Information). [ 18 ] In order to react completely, the reaction time in the first step was therefore set to be 20 h. In addition, Figure S3a, Supporting Information exhibited the transmission electron microscopy (TEM) image of pure NiSe 2 nanooctahedrons. The regular NiSe 2 nanooctahedrons with a mean size of about 250 nm exhibited smooth surfaces.…”

“…Two adjacent groups of well‐defined lattice fringes with an intersection angle of about 78.5° exhibited interplanar spacing of 0.267 and 0.267 nm (Figure S3b, Supporting Information), indexing to the (01$${{\bar{2}}}$$) and ($${{\bar{2}}}$$10) crystal planes of cubic phase NiSe 2 (JCPDS: 04‐003‐1991). [ 18 ] The detailed information of the standard cubic phase NiSe 2 (JCPDS: 04‐003‐1991) card was listed in Table S1, Supporting Information. The selected area electron diffraction (SAED) pattern in Figure S3c, Supporting Information also verified the chemical composition and crystal structure of the NiSe 2 precursor.…”

“…Three diffraction spots, which had interplanar spacing of 0.267, 0.267, and 0.211 nm, were indexed to the ($${{\bar{2}}}$$10), (01$${{\bar{2}}}$$), and (20$${{\bar{2}}}$$) crystal planes of cubic phase NiSe 2 (JCPDS: 04‐003‐1991), respectively. [ 18 ] Figure S3d, Supporting Information exhibited the high‐angle annular dark field scanning transmission electron microscopy (HAADF‐STEM) image of pure NiSe 2 precursor, and the energy dispersive X‐ray (EDX) mapping image in Figure S3e,f, Supporting Information exhibited the homogeneous elements distribution of Ni and Se in the NiSe 2 precursor. After the etching treatment in the second step, partial NiSe 2 was in situ transformed into Ni 0.85 Se, which mainly ascribed to the strong reducibility of NaBH 4 .…”

A Mini Review on Transition Metal Chalcogenides for Electrocatalytic Water Splitting: Bridging Material Design and Practical Application

“…92 The involvement of more than one metal elements offers high tunability of electronic structure. Our group 93,94 developed a facile electrodeposition and selenization process: Ni−Fe Prussian blue analogue (PBA)/ CFP was used as template to prepare Ni−Fe−Se nanocube structure (NiFeSe/CFP). The NiFeSe/CFP not only preserved the morphology characteristics of the MOF but also displayed higher specific surface area and abundant active sites, speeding up the intrinsic catalytic activity of HER and OER.…”