Natural photosynthesis converts carbon dioxide (CO₂) and water (H₂O) into hydrocarbons, providing a model for artificial systems designed to utilize the greenhouse gas CO₂ as a resource. However, artificial photosynthesis remains a significant challenge, primarily due to the short lifetimes of photogenerated electrons and holes—an issue that hinders the synchronized, sustained reduction of CO₂ and oxidation of H₂O.

Drawing inspiration from natural photosynthesis, a research team from the Institute of Earth Environment of the Chinese Academy of Sciences, has developed a universal approach to co-convert CO₂ and H₂O. Taking cues from plastoquinone's role in temporarily storing electrons during natural photosynthesis, the team designed a silver-modified tungsten trioxide (Ag/WO₃) material that acts as a charge reservoir through reversible W⁶⁺/W⁵⁺ transitions under irradiation. This capability allows the material to store photoexcited electrons and release them on demand, decoupling the two half-reactions in time and enabling more precise control over the reaction process.

Using this approach, the researchers combined Ag/WO₃ with cobalt phthalocyanine (CoPc) to develop a composite catalyst. This catalyst achieved a carbon monoxide (CO) production rate of approximately 1.5 mmol per gram of CoPc per hour—roughly 100 times higher than that of pure CoPc and comparable to the performance of systems using organic sacrificial agents.

Furthermore, the system operates stably under natural sunlight, offering a practical pathway to harness solar energy for converting CO₂ into clean fuels such as CO and methane (CH₄).

This work, recently published in Nature Communications, was supported by the National Natural Science Foundation of China and the State Key Laboratory of Loess Science.