Self-Supported Ceramic Electrode of 1T-2H MoS₂ Grown on the TiC Membrane for Hydrogen Production

Abstract

Binder-free, cost-effective, and stable hydrogen evolution reaction electrocatalytic electrodes with a customized size are urgently needed for large-scale industrial hydrogen production. Toward this challenge, self-supported TiC@MoS 2 (TCMS) ceramic membrane electrodes were fabricated by a self-template strategy. Porous TiC ceramic membranes with straight finger-like pores were first fabricated by phase inversion tape-casting and sintering. Then, a 1T-2H MoS 2 nanosheet layer grew on the porous conductive TiC skeleton. The high conductivity of the TCMS skeleton promotes charge transfer, while the porous structure, which consists of abundant finger-like and cavernous pores, favors proton transfer and bubble transfer during the electrolysis process. The optimal TCMS composition displayed an overpotential of −127 mV at −10 mA•cm −2 , a Tafel slope of 41 mV•dec −1 , and an extremely high electrochemical active area of 1079.4 mF•cm −2 as well as remarkable stability in 0.5 M H 2 SO 4 . A high Faradaic efficiency of 99.7% was also achieved. The superior electrocatalytic performance was ascribed to the synergistic effect of the tight bonding and the crystal matching between TiC and MoS 2 , the unique dual pore structure, the abundant exposed active sites of MoS 2 nanoflakes, and the high 1T-MoS 2 content. First-principles density functional calculations showed that the 1T-MoS 2 /TiC hybrid has the lowest free energy for H adsorption (0.116 eV) and the highest density of states near the Fermi level, which leads to a strong catalytic activity.

Robust Porous WC‐Based Self‐Supported Ceramic Electrodes for High Current Density Hydrogen Evolution Reaction

“…It is worth noting that, owing to the open pore structure of the membrane, it is proposed that C dl can be further significantly improved by optimizing the thermal‐treatment procedure. [ 12a ] Moreover, the intrinsic activity of the catalyst can be evaluated by calculating the ECSA. The WC‐N/W‐1200 electrode exhibited the largest ECSA among the prepared membrane electrodes in 0.5 m H 2 SO 4 (Table S3, Supporting Information).…”

“…The flexural strength ( σ F ) was calculated by the formula $$\begin{equation}\ {\sigma _F} = \frac{{3FL}}{{2b{h^2}}}\end{equation}$$where F is the maximum force applied, and L , b , and h are the length, width, and thickness of the ceramic membrane, respectively. [ 12b,48 ]…”

“…Hydrogen (H 2 ) was analyzed by Techcomp GC‐7900 gas chromatograph. [ 12a ] 5.0 mg Pt/C (20 wt% Pt) was dispersed in a mixed solution of 380 µL deionized water, 100 µL absolute ethanol, and 20 µL 0.5 wt% Nafion, and sonicated for 2 h to form a uniform catalyst ink. Then, 20 µL of the catalyst ink was deposited on the glassy carbon electrode with a mass loading of 1.0 mg cm −2 .…”

“…[ 11 ] Porous conductive ceramics are attractive candidates for self‐supported electrodes because of their high thermal and chemical stability, easy tailoring of pore structure, and high mechanical strength. [ 12 ] Additionally, the inherent hydrophilic properties of ceramic surfaces enhance the contact between the catalyst and the electrolyte, facilitate the transfer of charge and ions, and favor the detachment of bubbles. [ 13 ]…”

Biaxially Strained MoS2 Nanoshells with Controllable Layers Boost Alkaline Hydrogen Evolution

“…The phase transformation from 2H to the conductive 1T provides a new pathway to dramatically enhance the HER activity for TMDs, but this phase transition strategy generally requires critical condition and the metallic 1T-phase is thermodynamically less stable than the semiconducting 2H phase. [7] Very recently, nanomaterials with highly curved surfaces have been proved effective in energy-related reactions benefited from the inherent tensile strain and enhanced local electric field. [8][9][10] Introducing tensile strain into MoS 2 can favor the generation of sulfur vacancies as active sites to unlock the inert plane.…”