Synthesis of MoWS₂ on Flexible Carbon-Based Electrodes for High-Performance Hydrogen Evolution Reaction

Abstract

We directly synthesize MoWS2 nanosheets on conductive carbon nanotube yarn (MoWS2/CNTY) and carbon fiber cloth (MoWS2/CC) through a fast and low-temperature thermolysis method to obtain flexible catalyst electrodes that show high performance in the hydrogen evolution reaction. Small Tafel slopes of 41.8 and 46.7 mV dec–1 are achieved for MoWS2/CC and MoWS2/CNTY, respectively, by optimizing the density of the exposed active edge sites of vertically aligned MoWS2 on CNTY and CC. Furthermore, the catalyst electrodes demonstrate good electrocatalytic stability over 36 h. The proposed technique for fabricating high-performance, binder-free, and flexible catalyst electrodes is more accessible and faster than conventional methods.

Few‐Layered MoxW1−xS2‐Modified CdS Photocatalyst: One‐Step Synthesis with Bifunctional Precursors and Improved H2‐Evolution Activity

“…To be more interesting, some well‐marked layered structures are firmly sticked to the surface of CdS nanoparticles and these few‐layered structures can be undoubtedly indexed to the Mo x W 1− x S 2 cocatalyst (Figure 3A). Furthermore, as clearly observed in the high‐resolution image (Figure 3B), the Mo x W 1− x S 2 cocatalyst on CdS surface is in a few‐layered structure of 5–7 layers with an interlayer spacing of 0.65 nm, which is in high accordance with the (002) interlayer distance of Mo x W 1− x S 2 , [ 41,43 ] fully illustrating the successful fabrication of few‐layered Mo x W 1− x S 2 cocatalyst. In addition, as is evident in the element mapping results (Figure 3C), the Mo and W elements are uniformly distributed on the CdS surface, further elucidating the effective formation of few‐layered Mo x W 1− x S 2 cocatalyst on CdS surface.…”

“…In addition, based on the recent report in electrocatalytic H 2 evolution, Mo x W 1− x S 2 possesses significantly improved electrical conductivity compared with MoS 2 , which would lead to the high‐efficiency separation of photoinduced electron−hole pairs by quickly trapping and transferring the photoinduced electrons. [ 41,43 ] Apart from the above two facts, the seamless connection between the few‐layered Mo x W 1− x S 2 cocatalyst and CdS host photocatalyst, which is realized via the in situ conversion of MoS 4 2− and WS 4 2− into Mo x W 1− x S 2 on CdS surface, can also make contributions to the rapid shift of photoinduced electrons from CdS to Mo x W 1− x S 2 . In brief, considering the improved electrical conductivity and active‐site density by W‐introduction and the compact interface between Mo x W 1‐ x S 2 and CdS, the remarkable enhancement of photocatalytic H 2 ‐evolution activity for the few‐layered Mo x W 1− x S 2 /CdS photocatalyst can be ascribed to the significant promotion of photoexcited electron transport and interfacial H 2 ‐evolution process.…”

“…[ 39,40 ] For example, Nguyen et al synthesized vertically aligned MoWS 2 nanosheets on carbon‐based electrodes, which showed a high electrocatalytic H 2 ‐evolution performance due to more H 2 ‐evolution active sites and improved charge transfer from electrodes to MoWS 2 after incorporating W into the MoS 2 . [ 41 ] Lei et al fabricated a superior‐performance rGO/W x Mo 1− x S 2 heterostructure for electrocatalytic H 2 evolution, which could be ascribed to the excellent activation of inert basal plane in the binary MoS 2 via the formation of W x Mo 1− x S 2 alloys. [ 42 ] In addition, Wang et al confirmed that Mo 0.5 W 0.5 S 2 has the optimal H‐adsorption free energy and electric conductivity compared with the binary MoS 2 and WS 2 , which lead to the best electrocatalytic H 2 ‐evolution activity.…”

2D Layered Material Alloys: Synthesis and Application in Electronic and Optoelectronic Devices

“…Each of these techniques manifests its own advantages and disadvantages, and they will be critically introduced in detail below. It is noteworthy that a series of solution‐processed synthesis methods, such as, hydrothermal reaction, [ 99 , 100 , 101 ] thermolysis, [ 102 ] Schlenk line synthesis, [ 103 ] and liquid exfoliation, [ 104 , 105 ] suffer from insurmountable contamination issues (e.g., dispersants, residuals and by‐products), low crystalline quality of products and poor compatibility with the state‐of‐the‐art micro‐fabrication technology, which severely hamper their application in the field of electronic and optoelectronic devices. Therefore, these approaches have not been included in this review.…”

Boosting Hydrogen Evolution on MoS2/CNT Modified by Poly(sodium‐p–styrene sulfonate) via Proton Concentration in Acid Solution

“…However, their high cost and natural rarity restrict their large-scale industrial applications. [3,4] Thus, transition-metal-based materials are considered as the most promising substitute for the noblemental-based catalysts, such as alloys, [5,6] phosphides, [7,8] nitrides, [9,10] carbides, [11,12] sulfides, [13,14] selenides [15,16] and so on.…”