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Title: Improved transition metal photosensitizers to drive advances in photocatalysis

Journal Article · · Chemical Science
DOI: https://doi.org/10.1039/d3sc04580c · OSTI ID:2228376

To function effectively in a photocatalytic application, a photosensitizer's light absorption, excited-state lifetime, and redox potentials, both in the ground state and excited state, are critically important. The absorption profile is particularly relevant to applications involving solar harvesting, whereas the redox potentials and excited-state lifetimes determine the thermodynamics, kinetics, and quantum yields of photoinduced redox processes. This perspective article focuses on synthetic inorganic and organometallic approaches to optimize these three characteristics of transition-metal based photosensitizers. We include our own work in these areas, which has focused extensively on exceptionally strong cyclometalated iridium photoreductants that enable challenging reductive photoredox transformations on organic substrates, and more recent work which has led to improved solar harvesting in charge-transfer copper(I) chromophores, an emerging class of earth-abundant compounds particularly relevant to solar-energy applications. We also extensively highlight many other complementary strategies for optimizing these parameters and highlight representative examples from the recent literature. It remains a significant challenge to simultaneously optimize all three of these parameters at once, since improvements in one often come at the detriment of the others. These inherent trade-offs and approaches to obviate or circumvent them are discussed throughout.

Research Organization:
Univ. of Houston, TX (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Chemical Sciences, Geosciences & Biosciences Division (CSGB); National Science Foundation (NSF); Welch Foundation; USDOE
Grant/Contract Number:
SC0023394; CHE-1846831; E-1887
OSTI ID:
2228376
Alternate ID(s):
OSTI ID: 2281087
Journal Information:
Chemical Science, Vol. 15, Issue 1; ISSN 2041-6520
Publisher:
Royal Society of ChemistryCopyright Statement
Country of Publication:
United States
Language:
English

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