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Title: Rational Design of Porous Conjugated Polymers and Roles of Residual Palladium for Photocatalytic Hydrogen Production

Abstract

Developing high efficient photocatalyts for splitting water into oxygen and hydrogen is one of the biggest chemical challenges in solar energy utilization. In this paper, we report our effort in rationally designing conjugated porous polymer (CPP) photocatalysts for photocatalytic hydrogen production (PHP) from water. A series of CPP photocatalysts with different chromophore components and bipyridyl (bpy) contents were synthesized and found to evolve hydrogen photocatalytically from water. The PHP activity of bpy-containing CPPs can be greatly enhanced due to the improved light absorption, better wettability, higher crystallinity and the improved charge separation process. Moreover, the CPP photocatalyst made of strong and fully conjugated donor chromo-phore DBD shows the highest hydrogen production rate ~ 33 μmol/h. The results indicate that copolymerization between a strong donor and weak acceptor is a useful strategy for the devel-opment of efficient photocatalysts. This study clarifies that the residual palladium in the CPP networks plays a key role for the catalytic performance. The PHP activity of CPP photocatalyst can be further enhanced to 164 μmol/h with an apparent quantum yield of 1.8% at 350 nm by loading 2 wt% of extra platinum cocat-alyst.

Authors:
 [1];  [1];  [1];  [1];  [1];  [2];  [1]
  1. Department of Chemistry and the James Franck Institute, The University of Chicago, 929 East 57th Street, Chicago, Illinois 60637, United States
  2. Chemical Sciences and Engineering Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, United States; Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
OSTI Identifier:
1391992
DOE Contract Number:
AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of the American Chemical Society; Journal Volume: 138; Journal Issue: 24
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 36 MATERIALS SCIENCE

Citation Formats

Li, Lianwei, Cai, Zhengxu, Wu, Qinghe, Lo, Wai-Yip, Zhang, Na, Chen, Lin X., and Yu, Luping. Rational Design of Porous Conjugated Polymers and Roles of Residual Palladium for Photocatalytic Hydrogen Production. United States: N. p., 2016. Web. doi:10.1021/jacs.6b03472.
Li, Lianwei, Cai, Zhengxu, Wu, Qinghe, Lo, Wai-Yip, Zhang, Na, Chen, Lin X., & Yu, Luping. Rational Design of Porous Conjugated Polymers and Roles of Residual Palladium for Photocatalytic Hydrogen Production. United States. doi:10.1021/jacs.6b03472.
Li, Lianwei, Cai, Zhengxu, Wu, Qinghe, Lo, Wai-Yip, Zhang, Na, Chen, Lin X., and Yu, Luping. 2016. "Rational Design of Porous Conjugated Polymers and Roles of Residual Palladium for Photocatalytic Hydrogen Production". United States. doi:10.1021/jacs.6b03472.
@article{osti_1391992,
title = {Rational Design of Porous Conjugated Polymers and Roles of Residual Palladium for Photocatalytic Hydrogen Production},
author = {Li, Lianwei and Cai, Zhengxu and Wu, Qinghe and Lo, Wai-Yip and Zhang, Na and Chen, Lin X. and Yu, Luping},
abstractNote = {Developing high efficient photocatalyts for splitting water into oxygen and hydrogen is one of the biggest chemical challenges in solar energy utilization. In this paper, we report our effort in rationally designing conjugated porous polymer (CPP) photocatalysts for photocatalytic hydrogen production (PHP) from water. A series of CPP photocatalysts with different chromophore components and bipyridyl (bpy) contents were synthesized and found to evolve hydrogen photocatalytically from water. The PHP activity of bpy-containing CPPs can be greatly enhanced due to the improved light absorption, better wettability, higher crystallinity and the improved charge separation process. Moreover, the CPP photocatalyst made of strong and fully conjugated donor chromo-phore DBD shows the highest hydrogen production rate ~ 33 μmol/h. The results indicate that copolymerization between a strong donor and weak acceptor is a useful strategy for the devel-opment of efficient photocatalysts. This study clarifies that the residual palladium in the CPP networks plays a key role for the catalytic performance. The PHP activity of CPP photocatalyst can be further enhanced to 164 μmol/h with an apparent quantum yield of 1.8% at 350 nm by loading 2 wt% of extra platinum cocat-alyst.},
doi = {10.1021/jacs.6b03472},
journal = {Journal of the American Chemical Society},
number = 24,
volume = 138,
place = {United States},
year = 2016,
month = 6
}
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