Nanoporous Graphite-like Membranes Decorated with MoSe₂ Nanosheets for Hydrogen Evolution

Abstract

Self-standing binder-free materials have been intensively used as electrocatalytic electrodes for hydrogen production. Herein, the binder-free molybdenum selenide nanosheets on threedimensional macroporous reduced graphene oxide/graphite-like membrane (MoSe 2 /rGO-PGM) were proposed. A unique interconnected macroporous conducting carbon membrane was prepared by cryogelation and subsequent carbonization of the gelatin and graphene oxide cryogel. The conducting membrane is used as a substrate to synthesize MoSe 2 by the solvothermal method in which MoSe 2 -layered nanosheets are vertically grown on the surface. The MoSe 2 /rGO-PGM was applied as an electrocatalyst without binder "binder-free" for the water-splitting "hydrogen evolution reaction (HER)". The excellent electrochemical hydrogen generation exhibited a low onset potential of −0.15 V versus the reversible hydrogen electrode and a Tafel slope of 51 mV/decade. In addition, remarkable stability with no current decay for over 20,000 s of testing was observed. The perpendicular oriented nanostructure of the electrocatalyst on a highly carbon-based macroporous template favored more exposed active sites accompanied by an easily diffused electrolyte. The fabrication concept was successfully extended to synthesize other metal dichalcogenides which can be utilized as alternative nanomaterials for HER catalysts.

NiCoP/Mo3Se4 Nano‐Heterojunction as a Promising Bifunctional Catalyst for Full‐Water Splitting under Low Cell Voltage

“…As shown in Figure 2e, in the Mo 3d spectrum, peaks at 228.65 eV and 231.6 eV are typical peaks of Mo 3d 5/2 and 3d 3/2 , respectively [30] . Due to the inevitable surface oxidation process in the catalyst preparation process, the Mo 6+ at 235.49 eV also appeared [15] . Figure 2f shows the electron energy spectrum of Se 3d, in which 54.3 eV and 55.3 eV belong to Se 3d 5/2 and Se 3d 3/2 electron orbits [31] .…”

“…[30] Due to the inevitable surface oxidation process in the catalyst preparation process, the Mo 6 + at 235.49 eV also appeared. [15] Figure 2f shows the electron energy spectrum of Se 3d, in which 54.3 eV and 55.3 eV belong to Se 3d 5/2 and Se 3d 3/2 electron orbits. [31] The blue shift of combined energy of Se 3d in the as-prepared composites further demonstrated the successful preparation of NiCoP/ Mo 3 Se 4 heterojunction.…”

“…To enhance the dynamics of water splitting and reduce its business costs, active, cost‐effective, and robust electrical catalysts have emerged [5–7] . Among the previously reported catalysts, [8–10] low‐cost transition metal phosphides or selenides with unique charged properties and a wealth of non‐matching P‐atoms [11] or Se‐atoms, [12] which can be further modified have attracted great attention in electrolytic filed [13–15] . For example, NiCoP nanocomposites with high conductivity have been widely studied in HER [9,16–17] .…”

“…[5][6][7] Among the previously reported catalysts, [8][9][10] low-cost transition metal phosphides or selenides with unique charged properties and a wealth of nonmatching P-atoms [11] or Se-atoms, [12] which can be further modified have attracted great attention in electrolytic filed. [13][14][15] For example, NiCoP nanocomposites with high conductivity have been widely studied in HER. [9,[16][17] However, when NiCoP alone is used as a dual-function electrocatalyst for full hydrolysis, its electrocatalytic properties are severely limited.…”

Molecular Engineering Strategies toward Molybdenum Diselenide Design for Energy Storage and Conversion

“…Although the elaborated modification strategies yielded various structures, they increased the overall conductivity, accelerated the electron transfer, and improved the structural stability of MoSe 2 -based composites. [151][152][153][154] Core-shell structures are typical hierarchical structures, which are extensively used in energy applications owing to their rational functional division and synergistic effect. In particular, MoSe 2 can serve as the inner "core" or outer "shell," depending on its role in the composite.…”