Effect of Intercalated Metals on the Electrocatalytic Activity of 1T-MoS₂ for the Hydrogen Evolution Reaction

Abstract

We show that intercalation of cations (Na+, Ca2+, Ni2+, and Co2+) into the interlayer region of 1T-MoS2 is an effective strategy to lower the overpotential for the hydrogen evolution reaction (HER). In acidic media the onset potential for 1T-MoS2 with intercalated ions is lowered by ∼60 mV relative to that for pristine 1T-MoS2 (onset of ∼180 mV). Density functional theory (DFT) calculations show a lowering in the Gibbs free energy for H-adsorption (ΔG H) on these intercalated structures relative to intercalant-free 1T-MoS2. The DFT calculations suggest that Na+ intercalation results in a ΔG H close to zero. Consistent with calculation, experiments show that the intercalation of Na+ ions into the interlayer region of 1T-MoS2 results in the lowest overpotential for the HER.

Hierarchical Structure MnO2 Coated PDMS−Carbon Nanotube Sponge as Flexible Electrode for Electrocatalytic Water Splitting and High Performance Supercapacitor

“…These results strongly illustrate that CNTs join the composite to enhance the electrocatalytic activity, which was further confirmed by the small Tafel slope of 77 mV dec −1 of the PDMS−CNTs@MnO 2 sponge, because of the joint effect of CNTs and MnO 2 on enhancing electrocatalytic activity. The PDMS−CNTs sponge@MnO 2 showed the smallest Tafel slope of 71 mV dec −1 , approximate close to Pt/C in the reported values in the literature . As shown in Figure c, the combination of CNTs and MnO 2 resulted in an efficient functional electrocatalyst of PDMS−CNTs sponge@MnO 2 for HER.…”

Doping‐Assisted Phase Changing Effect on MoS2 Towards Hydrogen Evolution Reaction in Acidic and Alkaline pH

“…The HER performance is comparable with recently reported MoS 2 -based electrocatalysts. [20,22,24,27,38,32] It may be due to the improved in-plane electrical conductivity and carrier concentration of MoS 2 after nitrogen doping as observed in earlier cases for the nitrogen-manganese co-doped MoS 2 and nick-el@N-doped carbon@MoS 2 systems. [38,40] Therefore, the HER activity enhancement can be related to the N dopants in the MoS 2 crystal structure.…”

“…The other two relatively weak characteristic peaks appeared at ∼284 and 450 cm −1 belong to the E 1g and longitudinal acoustic phonon mode (2 nd order Raman scattering) for both 2H phase and hybrid phase composition. The spectrum drawn by a black color line contained three new characteristic peaks at 151, 234 and 340 cm −1 correspond to distinct phonon modes of J 1 , J 2 and J 3 , respectively, evidently signifying the formation of 1T@2H hybrid phase . The Raman spectra (Figure S1) of different phases of NMS1 and NMS3 agreed well with the XRD patterns shown in Figure (a‐c).…”

Ionic Liquid‐Intercalated Metallic MoS2 as a Superior Electrode for Energy Storage Applications

“…Nuvan et al. have also demonstrated that the higher interlayer spacing in 1T‐MoS 2 caused by the intercalation of metal cations showed reduced the overpotentials . Vertically aligned MoS 2 nanoflakes on the CC are very efficient in providing more active edge sites for the proton adsorption.…”

“…Nuvan et al have also demonstrated that the higher interlayer spacing in 1T-MoS 2 caused by the intercalation of metal cations showed reduced the overpotentials. [48] Vertically aligned MoS 2 nanoflakes on the CC are very efficient in providing more active edge sites for the proton adsorption. Furthermore, the direct growth of the MoS 2 onto the CC could reduce the contact resistance between the MoS 2 flakes and the current collector (carbon cloth).…”