Heterogeneous Nanostructure Based on 1T-Phase MoS₂ for Enhanced Electrocatalytic Hydrogen Evolution

Abstract

As an electrocatalyst, conventional 2H-phase MoS suffers from limited active sites and inherently low electroconductivity. Phase transitions from 2H to 1T have been proposed as an effective strategy for optimization of the catalytic activity. However, complicated chemical exfoliation is generally involved. Here, MoS heterogeneous-phase nanosheets with a 1T phase (1T/2H-MoS) generated in situ were prepared through a facile hydrothermal method. The locally introduced 1T-phase MoS can not only contribute more active sites but also markedly promote the electronic conductivity. Because of this unique structure, the as-synthesized 1T/2H-MoS nanosheets exhibit remarkable performance for the hydrogen evolution reaction with a small overpotential of 220 mV at 10 mA/cm, a small Tafel slope of 61 mV/decade, and robust stability. This work facilitates the development of a two-dimensional heterogeneous nanostructure with enhanced applications.

H2‐Directing Strategy on In Situ Synthesis of Co‐MoS2 with Highly Expanded Interlayer for Elegant HER Activity and its Mechanism

“…Therefore, the phase transition (2H → 1T) has also been reported to be an efficient approach to promote the electrocatalytic performance of MoS 2 . [ 25–29 ] Recently, Luxa et al [ 29 ] utilizing alkali metals (Li, Na, K, Rb, and Cs) as additives successfully increased 1T ratio on the prepared MoS 2 samples (41.9% for Li‐MoS 2 ), which thereby significantly improved the related HER activities. The sizes of intercalated cations were reported to strongly affect the final 1T ratio on MoS 2 .…”

A comparative study on the photocatalytic degradation of organic dyes using hybridized 1T/2H, 1T/3R and 2H MoS2 nano-sheets

“…Molybdenum disulde (MoS 2 ) is a 2D layered material with a graphene-like structure, which exhibits a variety of unique properties and enables applications as a catalyst in the hydrogen evolution reaction (HER), as a photo-catalyst, and for electrochemical energy storage. [1][2][3][4][5][6] This important material exists in two stable semiconducting phases with trigonal prismatic molybdenum centres (2H and 3R), and a metastable metallic octahedral phase (1T). 4 The higher conductivity and the more active basal plane of the 1T phase enabled a superior performance in energy storage and HER applications making it, thus, quite desirable.…”

Surface Engineering of MoS2 via Laser‐Induced Exfoliation in Protic Solvents

“…With the laser irradiation longer than 10 min, new Raman peaks have emerged at 147, 196, 236, and 336 cm −1 that are associated with the phonon modes of 1T MoS 2 . Another peak appeared at 284 cm −1 was identified as the E 1g band of 2H MoS 2 , suggesting the partial 2H‐to‐1T phase transition . These 1T peaks intensify with irradiation time, indicating more 1T phase has been produced in L‐MoS 2 ‐15 .…”

“…Another peak appeared at 284 cm -1 was identified as the E 1g band of 2H MoS 2 , suggesting the partial 2H-to-1T phase transition. [4,14,[26][27][28][29] These 1T peaks intensify with irradiation time, indicating more 1T phase has been produced in L-MoS 2 -15. [14] Further prolonged irradiation (20 min), however, results in the formation of metallic Mo, probably due to the excessive S loss (Figure S11, Supporting Information).…”