Tunable Pt−MoSx Hybrid Catalysts for Hydrogen Evolution

Tunable Pt−MoSx Hybrid Catalysts for Hydrogen Evolution

Článek WoS

Platinum (Pt)-based materials are inevitably among the best-performing electrocatalysts for hydrogen evolution reaction (HER). MoS2 was suggested to be a potent HER catalyst to replace Pt in this reaction by theoretical modeling; however, in practice, this dream remains elusive. Here we show a facile one-pot bottom-up synthesis of Pt−MoSx composites using electrochemical reduction in an electrolytic bath of Pt precursor and ammonium tetrathiomolybdate under ambient conditions. By modifying the millimolar concentration of Pt precursors, composites of different surface elemental composition are fabricated; specifically, Pt1.8MoS2, Pt0.1MoS2.5, Pt0.2MoS0.6, and Pt0.3MoS0.8. All electrodeposited Pt−MoSx hybrids showcase low overpotentials and small Tafel slopes that outperform MoS2 as an electrocatalyst. Tantamount to electrodeposited Pt, the rate-limiting process in the HER mechanism is determined to be the Heyrovsky desorption across Pt−MoSx hybrids and starkly swings from the ratedetermining Volmer adsorption step in MoS2. The Pt−MoSx composites are equipped with catalytic performance that closely mirrors that of electrodeposited Pt, in particular the HER kinetics for Pt1.8MoS2 and Pt0.1MoS2.5. This work advocates electrosynthesis as a cost-effective method for catalyst design and fabrication of competent composite materials for water splitting applications.

Platinum (Pt)-based materials are inevitably among the best-performing electrocatalysts for hydrogen evolution reaction (HER). MoS2 was suggested to be a potent HER catalyst to replace Pt in this reaction by theoretical modeling; however, in practice, this dream remains elusive. Here we show a facile one-pot bottom-up synthesis of Pt−MoSx composites using electrochemical reduction in an electrolytic bath of Pt precursor and ammonium tetrathiomolybdate under ambient conditions. By modifying the millimolar concentration of Pt precursors, composites of different surface elemental composition are fabricated; specifically, Pt1.8MoS2, Pt0.1MoS2.5, Pt0.2MoS0.6, and Pt0.3MoS0.8. All electrodeposited Pt−MoSx hybrids showcase low overpotentials and small Tafel slopes that outperform MoS2 as an electrocatalyst. Tantamount to electrodeposited Pt, the rate-limiting process in the HER mechanism is determined to be the Heyrovsky desorption across Pt−MoSx hybrids and starkly swings from the ratedetermining Volmer adsorption step in MoS2. The Pt−MoSx composites are equipped with catalytic performance that closely mirrors that of electrodeposited Pt, in particular the HER kinetics for Pt1.8MoS2 and Pt0.1MoS2.5. This work advocates electrosynthesis as a cost-effective method for catalyst design and fabrication of competent composite materials for water splitting applications.

molybdenum disulfide, platinum, doping, electrodeposition, hydrogen evolution

molybdenum disulfide, platinum, doping, electrodeposition, hydrogen evolution

CHIA, X.; SUTRISNOH, N.; PUMERA, M.

2020

14.03.2018

1944-8244

ACS Applied Materials & Interfaces

10

10

Spojené státy americké

8702

8711

10

https://pubs.acs.org/doi/abs/10.1021/acsami.7b19346