Imperial College London
Dr Xingyuan Shi

Dr Xingyuan Shi

Faculty of Natural Sciences, Department of Physics

Research Associate in Materials Chemistry
 
 
 
//

Contact

 

xingyuan.shi

 
 
//

Location

 

H704Huxley BuildingSouth Kensington Campus

//

Summary

 

Publications

Citation

BibTex format

@article{Hillman:2022:10.1021/jacs.2c07103,
author = {Hillman, SAJ and Sprick, RS and Pearce, D and Woods, DJ and Sit, W-Y and Shi, X and Cooper, AI and Durrant, JR and Nelson, J},
doi = {10.1021/jacs.2c07103},
journal = {Journal of the American Chemical Society},
pages = {19382--19395},
title = {Why do sulfone-containing polymer photocatalysts work so well for sacrificial hydrogen evolution from water?},
url = {http://dx.doi.org/10.1021/jacs.2c07103},
volume = {144},
year = {2022}
}
Download

RIS format (EndNote, RefMan)

TY  - JOUR
AB  - Many of the highest-performing polymer photocatalysts for sacrificial hydrogen evolution from water have contained dibenzo[b,d]thiophene sulfone units in their polymer backbones. However, the reasons behind the dominance of this building block are not well understood. We study films, dispersions, and solutions of a new set of solution-processable materials, where the sulfone content is systematically controlled, to understand how the sulfone unit affects the three key processes involved in photocatalytic hydrogen generation in this system: light absorption; transfer of the photogenerated hole to the hole scavenger triethylamine (TEA); and transfer of the photogenerated electron to the palladium metal co-catalyst that remains in the polymer from synthesis. Transient absorption spectroscopy and electrochemical measurements, combined with molecular dynamics and density functional theory simulations, show that the sulfone unit has two primary effects. On the picosecond timescale, it dictates the thermodynamics of hole transfer out of the polymer. The sulfone unit attracts water molecules such that the average permittivity experienced by the solvated polymer is increased. We show that TEA oxidation is only thermodynamically favorable above a certain permittivity threshold. On the microsecond timescale, we present experimental evidence that the sulfone unit acts as the electron transfer site out of the polymer, with the kinetics of electron extraction to palladium dictated by the ratio of photogenerated electrons to the number of sulfone units. For the highest-performing, sulfone-rich material, hydrogen evolution seems to be limited by the photogeneration rate of electrons rather than their extraction from the polymer.
AU  - Hillman,SAJ
AU  - Sprick,RS
AU  - Pearce,D
AU  - Woods,DJ
AU  - Sit,W-Y
AU  - Shi,X
AU  - Cooper,AI
AU  - Durrant,JR
AU  - Nelson,J
DO  - 10.1021/jacs.2c07103
EP  - 19395
PY  - 2022///
SN  - 0002-7863
SP  - 19382
TI  - Why do sulfone-containing polymer photocatalysts work so well for sacrificial hydrogen evolution from water?
T2  - Journal of the American Chemical Society
UR  - http://dx.doi.org/10.1021/jacs.2c07103
UR  - https://www.webofscience.com/wos/woscc/full-record/WOS:000874707600001
UR  - https://pubs.acs.org/doi/10.1021/jacs.2c07103
UR  - http://hdl.handle.net/10044/1/100344
VL  - 144
ER  -
Download