Engineering 2D Metal–Organic Framework/MoS₂ Interface for Enhanced Alkaline Hydrogen Evolution

Abstract

2D metal–organic frameworks (MOFs) have been widely investigated for electrocatalysis because of their unique characteristics such as large specific surface area, tunable structures, and enhanced conductivity. However, most of the works are focused on oxygen evolution reaction. There are very limited numbers of reports on MOFs for hydrogen evolution reaction (HER), and generally these reported MOFs suffer from unsatisfactory HER activities. In this contribution, novel 2D Co‐BDC/MoS2 (BDC stands for 1,4‐benzenedicarboxylate, C8H4O4) hybrid nanosheets are synthesized via a facile sonication‐assisted solution strategy. The introduction of Co‐BDC induces a partial phase transfer from semiconducting 2H‐MoS2 to metallic 1T‐MoS2. Compared with 2H‐MoS2, 1T‐MoS2 can activate the inert basal plane to provide more catalytic active sites, which contributes significantly to improving HER activity. The well‐designed Co‐BDC/MoS2 interface is vital for alkaline HER, as Co‐BDC makes it possible to speed up the sluggish water dissociation (rate‐limiting step for alkaline HER), and modified MoS2 is favorable for the subsequent hydrogen generation step. As expected, the resultant 2D Co‐BDC/MoS2 hybrid nanosheets demonstrate remarkable catalytic activity and good stability toward alkaline HER, outperforming those of bare Co‐BDC, MoS2, and almost all the previously reported MOF‐based electrocatalysts.

Designing MOF Nanoarchitectures for Electrochemical Water Splitting

“…[8,20] In one study, novel 2D Co-BDC/MoS 2 hybrid nanosheets (Figure 10Ba) were designed and fabricated as efficient electrocatalysts for alkaline HER via a simple sonication-assisted solution strategy. [154] As shown in Figure 10Bb, the introduction of Co-BDC in the Co-BDC/MoS 2 resulted in a partial phase transfer from 2H-MoS 2 to 1T-MoS 2 , which contributes significantly to enhanced HER activity. The Co-BDC/MoS 2 required a lower overpotential at −10 mA cm −2 , lower Tafel slope, and lower charge-transfer resistance than bare Co-BDC and MoS 2 in 1 m KOH (Figure 10Bc,e,f).…”

“…e) Tafel plots and f) Nyquist plots of Co-BDC/MoS 2 and corresponding counterparts. B) Reproduced with permission [154]. Copyright 2019, Wiley-VCH.…”

Structure Engineering of MoS2 via Simultaneous Oxygen and Phosphorus Incorporation for Improved Hydrogen Evolution

“…Nevertheless, bulk MoS 2 often shows poor performance for HER, due to the limited active sites. To overcome this drawback, a variety of nanostructured MoS 2 (e.g., nanosheets, nanoparticles, nanofilms, nanocomposites, and quantum dots) has been fabricated to release the active sites. Despite the relatively improved HER performance, there are still some concerns associated with nanostructured MoS 2 .…”

Mesoporous Carbon Nanotablets Coupled with Mo2C Nanoparticles: Combining Morphology and Structure to Realize High Activity for Efficient Hydrogen Evolution

“…[3] However, the challenges of hydrogen evolution reaction (HER) rely on design and synthesis of outstanding electrocatalysts. [4] Although Ptbased catalysts are confirmed to be high active electrocatalyst for HER, [5,6] Pt-free materials including transition metal carbides, [7] sulfides, [8][9][10] and oxide materials [11] are expected to substitute for noble metal as electrocatalysts for water splitting because of their low cost and high abundance in nature.…”