TY - JOUR
T1 - Catalysts for the hydrogen evolution reaction in alkaline medium
T2 - Configuring a cooperative mechanism at the Ag-Ag2S-MoS2 interface
AU - Bar-Hen, Avraham
AU - Hettler, Simon
AU - Ramasubramaniam, Ashwin
AU - Arenal, Raul
AU - Bar-Ziv, Ronen
AU - Bar Sadan, Maya
N1 - Funding Information:
This research was supported by the United States-Israel Binational Science Foundation (BSF), Jerusalem, Israel and the United States National Science Foundation (NSF) grant 2017642, and partly from the Israeli Atomic Energy Commission–Prof. A. Pazy joint foundation, ID126-2020. S.H. and R.A. acknowledge funding from the European Union’s Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 889546 as well as from the Spanish MICINN (project grant PID2019-104739GB-100/AEI/10.13039/501100011033). R.A. also support the funding from the European Union H2020 program Graphene Flagship CORE3 (881603). Some of the TEM measurements were performed in the Laboratorio de Microscopias Avanzadas (LMA) at the Universidad de Zaragoza (Spain).
Funding Information:
This research was supported by the United States-Israel Binational Science Foundation (BSF), Jerusalem, Israel and the United States National Science Foundation (NSF) grant 2017642, and partly from the Israeli Atomic Energy Commission–Prof. A. Pazy joint foundation, ID126-2020. S.H. and R.A. acknowledge funding from the European Union's Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant agreement No 889546 as well as from the Spanish MICINN (project grant PID2019-104739GB-100/AEI/10.13039/501100011033). R.A. also support the funding from the European Union H2020 program Graphene Flagship CORE3 (881603). Some of the TEM measurements were performed in the Laboratorio de Microscopias Avanzadas (LMA) at the Universidad de Zaragoza (Spain).
Publisher Copyright:
© 2022 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences
PY - 2022/11/1
Y1 - 2022/11/1
N2 - Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen economy. To this end, delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and, specifically, making use of hybrid structures, can produce synergistic effects that lead to highly active catalysts. Here, we present a core-shell catalyst of Ag@MoS2 that shows promising results towards the hydrogen evolution reaction (HER) in both 0.5 M H2SO4 and 0.5 M KOH. In this hybrid structure, the MoS2 shell is strained and defective, and charge transfer occurs between the conductive core and the shell, contributing to the electrocatalytic activity. The shelling process results in a large fraction of Ag2S in the cores, and adjusting the relative fractions of Ag, Ag2S, and MoS2 leads to improved catalytic activity and fast charge-transfer kinetics. We suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces, where the Ag(I) sites in Ag2S drive the water dissociation step, and the formed hydrogen subsequently recombines on the defective MoS2 shell. This study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS2 for HER in alkaline conditions.
AB - Designing electrocatalysts for HER in alkaline conditions to overcome the sluggish kinetics associated with the additional water dissociation step is a recognized challenge in promoting the hydrogen economy. To this end, delicately tuning the atomic-scale structure and surface composition of nanoparticles is a common strategy and, specifically, making use of hybrid structures, can produce synergistic effects that lead to highly active catalysts. Here, we present a core-shell catalyst of Ag@MoS2 that shows promising results towards the hydrogen evolution reaction (HER) in both 0.5 M H2SO4 and 0.5 M KOH. In this hybrid structure, the MoS2 shell is strained and defective, and charge transfer occurs between the conductive core and the shell, contributing to the electrocatalytic activity. The shelling process results in a large fraction of Ag2S in the cores, and adjusting the relative fractions of Ag, Ag2S, and MoS2 leads to improved catalytic activity and fast charge-transfer kinetics. We suggest that the enhancement of alkaline HER is associated with a cooperative effect of the interfaces, where the Ag(I) sites in Ag2S drive the water dissociation step, and the formed hydrogen subsequently recombines on the defective MoS2 shell. This study demonstrates the benefits of hybrid structures as functional nanomaterials and provides a scheme to activate MoS2 for HER in alkaline conditions.
KW - 2D materials
KW - Catalytic mechanism
KW - Core-shell
KW - Electrocatalysis
KW - Water splitting
UR - http://www.scopus.com/inward/record.url?scp=85136461275&partnerID=8YFLogxK
U2 - 10.1016/j.jechem.2022.07.020
DO - 10.1016/j.jechem.2022.07.020
M3 - Article
AN - SCOPUS:85136461275
SN - 2095-4956
VL - 74
SP - 481
EP - 488
JO - Journal of Energy Chemistry
JF - Journal of Energy Chemistry
ER -
