TY - JOUR
T1 - Edge-site nano-engineering of WS2 by low temperature plasma-enhanced atomic layer deposition for electrocatalytic hydrogen evolution
AU - Balasubramanyam, Shashank
AU - Shirazi, Mahdi
AU - Bloodgood, Matthew
AU - Wu, Longfei
AU - Verheijen, Marcel
AU - Vandalon, Vincent
AU - Kessels, Erwin
AU - Hofmann, Jan Philipp
AU - Bol, Ageeth A.
PY - 2019/6/25
Y1 - 2019/6/25
N2 - Edge-enriched transition metal dichalcogenides, such as WS
2, are promising electrocatalysts for sustainable production of H
2 through the electrochemical hydrogen evolution reaction (HER). The reliable and controlled growth of such edge-enriched electrocatalysts at low temperatures has, however, remained elusive. In this work, we demonstrate how plasma-enhanced atomic layer deposition (PEALD) can be used as a new approach to nanoengineer and enhance the HER performance of WS
2 by maximizing the density of reactive edge sites at a low temperature of 300 °C. By altering the plasma gas composition from H
2S to H
2 + H
2S during PEALD, we could precisely control the morphology and composition and, consequently, the edge-site density as well as chemistry in our WS
2 films. The precise control over edge-site density was verified by evaluating the number of exposed edge sites using electrochemical copper underpotential depositions. Subsequently, we demonstrate the HER performance of the edge-enriched WS
2 electrocatalyst, and a clear correlation among plasma conditions, edge-site density, and the HER performance is obtained. Additionally, using density functional theory calculations we provide insights and explain how the addition of H
2 to the H
2S plasma impacts the PEALD growth behavior and, consequently, the material properties, when compared to only H
2S plasma.
AB - Edge-enriched transition metal dichalcogenides, such as WS
2, are promising electrocatalysts for sustainable production of H
2 through the electrochemical hydrogen evolution reaction (HER). The reliable and controlled growth of such edge-enriched electrocatalysts at low temperatures has, however, remained elusive. In this work, we demonstrate how plasma-enhanced atomic layer deposition (PEALD) can be used as a new approach to nanoengineer and enhance the HER performance of WS
2 by maximizing the density of reactive edge sites at a low temperature of 300 °C. By altering the plasma gas composition from H
2S to H
2 + H
2S during PEALD, we could precisely control the morphology and composition and, consequently, the edge-site density as well as chemistry in our WS
2 films. The precise control over edge-site density was verified by evaluating the number of exposed edge sites using electrochemical copper underpotential depositions. Subsequently, we demonstrate the HER performance of the edge-enriched WS
2 electrocatalyst, and a clear correlation among plasma conditions, edge-site density, and the HER performance is obtained. Additionally, using density functional theory calculations we provide insights and explain how the addition of H
2 to the H
2S plasma impacts the PEALD growth behavior and, consequently, the material properties, when compared to only H
2S plasma.
UR - http://www.scopus.com/inward/record.url?scp=85070541798&partnerID=8YFLogxK
U2 - 10.1021/acs.chemmater.9b01008
DO - 10.1021/acs.chemmater.9b01008
M3 - Article
C2 - 31371869
VL - 31
SP - 5104
EP - 5115
JO - Chemistry of Materials
JF - Chemistry of Materials
SN - 0897-4756
IS - 14
ER -