A lotus-inspired triphase continuous CO₂ photo-thermal reduction system with wide applicability and tunable interface environment

Constructing a collaborative catalytic reaction system can boost the CO₂ photoreduction reaction, beyond developing high-performance photocatalysts. Here, inspired by the photosynthesis of lotus, we propose a continuous triphase reaction system for boosting CO₂ conversion. Compared with the traditional liquid-solid and gas-solid reactions, the experimental and theoretical calculation results show that the system spontaneously optimizes the supply path of reaction gas and reaction liquid by using the phenomena of capillarity and evaporation, and effectively changes the supply ratio of reaction gas and liquid near the catalyst. Using Bi and Ti co-doped g-C₃N₄ as a representative catalyst, the performances of three common reactions with sacrificial agents, non-sacrificial agents and coupled oxidation dual reactions were studied systematically under different reaction systems. The results show that the system has a good promoting effect on all three reaction conditions, a reasonable reactant supply ratio is spontaneously formed near the catalyst, and the auxiliary solution can be easily supplemented. In the dual reaction coupling system, the highest triphase efficiency can reach 0.0458 %, which is nearly 10 times that of the liquid-solid phase reaction. The proposed reaction system can effectively improve the catalytic activity of various reaction modes and supports large-scale application of photocatalysis in the future.