Rapid growth in the world’s economy depends on a significant increase in energy consumption. As is known, most of the present energy supply comes from coal, oil, and natural gas. The overreliance on fossil energy brings serious environmental problems in addition to the scarcity of energy. One of the most concerning environmental problems is the large contribution to global warming because of the massive discharge of CO2 in the burning of fossil fuels. Therefore, many efforts have been made to resolve such issues. Among them, the preparation of valuable fuels or chemicals from greenhouse gas (CO2) has attracted great attention because it has made a promising step toward simultaneously resolving the environment and energy problems. This article reviews the current progress in CO2 conversion via different strategies, including thermal catalysis, electrocatalysis, photocatalysis, and photoelectrocatalysis. Inspired by natural photosynthesis, light-capturing agents including macrocycles with conjugated structures similar to chlorophyll have attracted increasing attention. Using such macrocycles as photosensitizers, photocatalysis, photoelectrocatalysis, or coupling with enzymatic reactions were conducted to fulfill the conversion of CO2 with high efficiency and specificity. Recent progress in enzyme coupled to photocatalysis and enzyme coupled to photoelectrocatalysis were specially reviewed in this review. Additionally, the characteristics, advantages, and disadvantages of different conversion methods were also presented. We wish to provide certain constructive ideas for new investigators and deep insights into the research of CO2 conversion.

We constructed hierarchical complexes via the peptide-regulated assembly of porphyrin and Pt for converting light energy into chemical energy and storing it as NADH.

Natural photosynthesis provides a perfect example of solar energy utilization that converts CO2 to carbohydrates at high efficiency. Herein, an innovative approach was developed to construct light-harvesting antennas via the precise control of porphyrin aggregation and platinum organization on the surface of the self-assembled structures of Fmoc-blocked peptides (Fmoc-ChaChaGK-NH2 and Fmoc-FFGK-NH2). The photophysical properties and the photocatalytic activity of the antenna are dependent on the aggregating structure of porphyrin and arrangement of Pt nanoparticles, which are related closely to the molecular structure of peptides, as well as to the peptide/porphyrin molar ratio and their concentrations. The Fmoc-ChaChaGK/porphyrin complexes prepared at a peptide (Fmoc-ChaChaGK)/TPPS molar ratio of 2 and TPPS concentration of 500 μM possess the highest photo-to-electric conversion efficiency and photocatalytic ability in transforming light energy into chemical energy and storing in the energy-storage molecules (reduced nicotinamide adenine dinucleotide, NADH). The results demonstrate the correlation between the hierarchical structure and light-responsive properties of the antenna and highlight the mediating effect of noncovalent interactions in the construction and stabilization of the photoresponsive materials.

No abstract