Engineering Monolayer 1T-MoS₂ into a Bifunctional Electrocatalyst via Sonochemical Doping of Isolated Transition Metal Atoms

Abstract

There has been an intense research to develop 2-H MoS2 based catalysts to reduce or eliminate the use of Pt/C at higher metal loading for hydrogen evolution reaction (HER) in catalytic hydrolysis of water, which enables the capture of renewable energy sources as fuel and chemical. However, the study of its uncommon polymorph, 1T-MoS2 and particularly the doping effect with transition metal (TM) is rather limited due to the instability of this phase. Here we report a simple ambient temperature modification method using sonication to dope the single layer 1T-S MoS2 with various TM precursors. It is found that 1-T S MoS2 is more superior than corresponding 2H-S MoS2 and the inclusion of 3 wt% Pt or Pd can also further enhance the HER activity. STEM-EELS and XAS show the active single TM atom doping on this surface is to account for the high activity. Kinetic and DFT analyses also illustrate that the metallic nature of 1T-S MoS2 greatly facilitates the first proton reduction step from water, rendering it non-rate limiting as contrast to that of 2H-S MoS2. The inclusion of TM single doper such as Pd, despite at low loading, can offer the dramatic acceleration on the rate limiting recombination of H to H2. As a result, a bifunctional catalysis for HER over this tailored composite structure is demonstrated which outperforms most reported catalysts in this area.

Multifunctional Transition Metal‐Based Phosphides in Energy‐Related Electrocatalysis

“…Admittedly, in most cases, the preparation of TMDs undergoes a much milder condition as compared with TMPs' synthesis. It is worth noting that the most stable and only naturally occurring polymorph of TMDs is the 2H phase . While its semiconductor nature and edge distributed active sites undoubtedly bring detrimental effects on electrocatalysis.…”

Platinum Atoms and Nanoparticles Embedded Porous Carbons for Hydrogen Evolution Reaction

“…Therefore, hydrogen from water splitting is more favorable in view of its relatively long history and environmental protection characteristics. As a result, more and more researchers have focused on the exploration of high efficient electrocatalysts for hydrogen evolution reaction (HER) [19,20]. So far, platinum (Pt)-based electrocatalysts are the benchmark for HER [21][22][23][24], because of their superior performance, although many kinds of electrocatalysts, such as metal alloys [25], oxides [26], carbides [27], nitrides [28], phosphides [29], and carbon-based nanomaterials [30], etc., have been developed.…”

Recent advances in single metal atom-doped MoS2 as catalysts for hydrogen evolution reaction

“…In addition to precious metal dopants, non-precious Co dopant was also predicted and demonstrated as a good candidate for tuning the catalytic activity of MoS 2 [40,43,57,60,61]. SA-Co doped mesoporous MoS 2 foam prepared via an impregnation procedure was reported by Deng et al [47].…”

“…With the fast development of SA-doped MoS 2 and other TMD catalysts, some other intelligently designed synthesis strategies have been reported. For example, sonication was reported to dope single-layer 1T MoS 2 with various transition metal precursors [57]. The chemically exfoliated 1T MoS 2 and H 2 PtCl 4 were used as precursors, and SA-Pt doped MoS 2 was formed after a 24-h sonication treatment.…”

“…[41]. Copyright 2019 ACS the lattices of MoS 2 for HER application and showed an enhanced performance, including Pd [57], Rh [59] and Ru [36].…”