RESUMO
Solar-driven high-efficiency conversion of CO2 with water vapor into high-value-added alcohols is a promising approach for reducing CO2 emissions and achieving carbon neutrality. However, the rapid recombination of photogenerated carriers and low CO2 adsorption capacity of photocatalysts are usually the factors that limit their applicability. Herein, a series of low-cost Z-scheme heterostructures Cu2O/PCN-250-x are constructed by in situ growth of ultrasmall Cu2O nanoparticles on PCN-250. A systematic investigation revealed that there is a strong interaction between Cu2O nanoparticles and PCN-250. The resulting Cu2O/PCN-250-2 exhibits excellent photogenerated carrier separation efficiency and CO2 adsorption capacity, which dramatically promote the conversion of CO2 into alcohols. Notably, the total yield of 268 µmol gcat-1 for the production of CH3OH and CH3H2OH is superior to that of isolated PCN-250 and Cu2O. This study provides a new perspective for the design of a Cu2O nanoparticle/metal-organic framework Z-scheme heterojunction for the reduction of CO2 to alcohols with water vapor.
RESUMO
The photocatalytic reduction of CO2 represents an environmentally friendly and sustainable approach for generating valuable chemicals. In this study, a thiophene-modified highly conjugated asymmetric covalent triazine framework (As-CTF-S) is developed for this purpose. Significantly, single-component intramolecular energy transfer can enhance the photogenerated charge separation, leading to the efficient conversion of CO2 to CO during photocatalysis. As a result, without the need for additional photosensitizers or organic sacrificial agents, As-CTF-S demonstrates the highest photocatalytic ability of 353.2 µmol g-1 and achieves a selectivity of ≈99.95% within a 4 h period under visible light irradiation. This study provides molecular insights into the rational control of charge transfer pathways for high-efficiency CO2 photoreduction using single-component organic semiconductor catalysts.