Unveiling the Interfacial Effects for Enhanced Hydrogen Evolution Reaction on MoS₂/WTe₂ Hybrid Structures

Abstract

Using the MoS2‐WTe2 heterostructure as a model system combined with electrochemical microreactors and density function theory calculations, it is shown that heterostructured contacts enhance the hydrogen evolution reaction (HER) activity of monolayer MoS2. Two possible mechanisms are suggested to explain this enhancement: efficient charge injection through large‐area heterojunctions between MoS2 and WTe2 and effective screening of mirror charges due to the semimetallic nature of WTe2. The dielectric screening effect is proven minor, probed by measuring the HER activity of monolayer MoS2 on various support substrates with dielectric constants ranging from 4 to 300. Thus, the enhanced HER is attributed to the increased charge injection into MoS2 through large‐area heterojunctions. Based on this understanding, a MoS2/WTe2 hybrid catalyst is fabricated with an HER overpotential of −140 mV at 10 mA cm−2, a Tafel slope of 40 mV dec−1, and long stability. These results demonstrate the importance of interfacial design in transition metal dichalcogenide HER catalysts. The microreactor platform presents an unambiguous approach to probe interfacial effects in various electrocatalytic reactions.

Synthesis of tungsten ditelluride thin films and highly crystalline nanobelts from pre-deposited reactants

“…Additionally, WTe 2 has been touted as a promising candidate for large-gap quantum spin Hall insulators [5,21,22]. Lastly, through electrochemical investigations, the possibility of using WTe 2 as a catalyst for the hydrogen evolution reaction (HER) has been examined [24,[27][28][29][30].…”

Design of 2D Layered Catalyst by Coherent Heteroepitaxial Conversion for Robust Hydrogen Generation

“…These results suggest that out‐of‐plane deformation via the transformation of atomic‐scale structures can substantially enhance the interfacial electron‐transfer kinetics of these systems. [ 40 ] One of the important descriptors for HER catalysts is the turnover frequency (TOF, the number of hydrogen molecules evolved per second), which is the basis for determining the inherent electrocatalytic activity. We calculated the TOF values according to previous literature [ 39 ] (Figure S22, Supporting Information).…”

Seamlessly Splicing Metallic SnxMo1−xS2 at MoS2 Edge for Enhanced Photoelectrocatalytic Performance in Microreactor

“…The MoS 2 -based lateral heterointerfaces have been found to markedly enhance H 2 or O 2 production efficiency. [13,17,18] A more elaborate design was the epitaxial M-S heterostructures, which were considered as intriguing building blocks for low-power, high-performance, and flexible electronic and optoelectronic devices. [19][20][21] In the artificially in-plane M-S heterostructures, the metallic 2D materials governed internal electrical transport, and the covalent connection replaced traditional physical electrode contact, which can dramatically improve charge injection, thus enhancing electrical performance.…”