TY - JOUR
T1 - Reaction Intermediates in Artificial Photosynthesis with Molecular Catalysts
AU - Hong, Young Hyun
AU - Lee, Yong Min
AU - Nam, Wonwoo
AU - Fukuzumi, Shunichi
N1 - Funding Information:
The authors gratefully acknowledge the significant contributions of their collaborators and co-workers cited in the references and financial support from JSPS (grant number 16H02268 to S.F.) from Ministry of Education, Culture, Sports, Science and Technology (MEXT), Japan, the NRF of Korea through the CRI (NRF-2021R1A3B1076539 to W.N.), and Basic Science Research Program (NRF-2020R1I1A1A01074630 to Y.-M.L. and NRF-2020R1A6A3A13072451 to Y.H.H.).
Publisher Copyright:
© 2023 American Chemical Society. All rights reserved.
PY - 2023/1/6
Y1 - 2023/1/6
N2 - In nature, water oxidation is catalyzed by Mn4Ca clusters in the oxygen-evolving complex (OEC) of photosystem II (PSII), in which a manganese(V)-oxo species acts as an active reaction intermediate. Electrons and protons taken from water in PSII are used to reduce plastoquinone to plastoquinol via photoinduced charge separation in the photosynthetic reaction center. In photosystem I (PSI), NADP+coenzyme is reduced by plastoquinol via photoinduced charge separation in the photosynthetic reaction center to produce NADPH, which is used as a reductant to reduce CO2to carbohydrates in the Calvin cycle. Extensive efforts have so far been made to mimic functions of PSII and PSI for photocatalytic water oxidation and reduction to produce O2and H2, respectively. Characterization and reactivity of high-valent metal-oxo, -hydroperoxo, -peroxo, and -superoxo intermediates have been investigated to clarify the mechanisms of water oxidation. Metal hydride complexes have also been studied in relation with the catalytic reactivity for water reduction to produce H2as well as NAD+reduction to NADH. This Review is intended to provide an overview on the functional model reactions of PSII and PSI for the photocatalytic water oxidation and reduction, respectively. The roles of high-valent metal-oxo, -hydroperoxo, -peroxo, and -superoxo complexes as the reaction intermediates in photocatalytic water oxidation are focused in relation with the catalytic mechanisms of water oxidation. The roles of metal hydride complexes are also discussed in relation with the catalytic mechanisms of hydrogen evolution and NAD+reduction to NADH. The combination of functional model reactions of PSII and PSI leads to construct molecular artificial photosynthetic systems in which water is split to H2and O2in a 2:1 ratio, providing a way to realize artificial photosynthesis in molecular levels.
AB - In nature, water oxidation is catalyzed by Mn4Ca clusters in the oxygen-evolving complex (OEC) of photosystem II (PSII), in which a manganese(V)-oxo species acts as an active reaction intermediate. Electrons and protons taken from water in PSII are used to reduce plastoquinone to plastoquinol via photoinduced charge separation in the photosynthetic reaction center. In photosystem I (PSI), NADP+coenzyme is reduced by plastoquinol via photoinduced charge separation in the photosynthetic reaction center to produce NADPH, which is used as a reductant to reduce CO2to carbohydrates in the Calvin cycle. Extensive efforts have so far been made to mimic functions of PSII and PSI for photocatalytic water oxidation and reduction to produce O2and H2, respectively. Characterization and reactivity of high-valent metal-oxo, -hydroperoxo, -peroxo, and -superoxo intermediates have been investigated to clarify the mechanisms of water oxidation. Metal hydride complexes have also been studied in relation with the catalytic reactivity for water reduction to produce H2as well as NAD+reduction to NADH. This Review is intended to provide an overview on the functional model reactions of PSII and PSI for the photocatalytic water oxidation and reduction, respectively. The roles of high-valent metal-oxo, -hydroperoxo, -peroxo, and -superoxo complexes as the reaction intermediates in photocatalytic water oxidation are focused in relation with the catalytic mechanisms of water oxidation. The roles of metal hydride complexes are also discussed in relation with the catalytic mechanisms of hydrogen evolution and NAD+reduction to NADH. The combination of functional model reactions of PSII and PSI leads to construct molecular artificial photosynthetic systems in which water is split to H2and O2in a 2:1 ratio, providing a way to realize artificial photosynthesis in molecular levels.
KW - artificial photosynthesis
KW - molecular catalyst
KW - photosystems I and II
KW - reaction intermediate
KW - reaction mechanism
KW - water splitting
UR - http://www.scopus.com/inward/record.url?scp=85144465821&partnerID=8YFLogxK
U2 - 10.1021/acscatal.2c05033
DO - 10.1021/acscatal.2c05033
M3 - Review article
AN - SCOPUS:85144465821
SN - 2155-5435
VL - 13
SP - 308
EP - 341
JO - ACS Catalysis
JF - ACS Catalysis
IS - 1
ER -