CO₂ Adsorption-Mediated Oxygen Defects for Photothermal Catalysis Self-Decomposition over Low-Crystalline Nb₂O₅ Nanoribbons

The direct decomposition of CO2 to produce CO and O-2 requires extremely high temperatures in catalysis. Here, we proposed the photoassisted oxygen vacancy active sites for CO2 dissociation to lower the reaction temperature. The designed low-crystalline Nb2O5 nanoribbons (LC-Nb2O5 NRs) showed a good CO production rate under mild conditions (<= 250 degrees C) with Xe lamp irradiation. Under light irradiation, the rate of CO yields of LC-Nb2O5 NRs increased to 68 mu mol g(-1) h(-1) at 250 degrees C, with no activity at all under light conditions. The high activity arose from unsaturated coordination with low crystallinity and CO2 reactants as an electron donor for forming an electron cycle with the Nb2O5 NRs, which played a key role in the generation of oxygen vacancies for the subsequent photoexcited electron transfer process at mild temperatures. The feasibility of this approach is further verified over Nb2O5/C nanofibers that make full use of photothermal and photoelectric effects to achieve long-term stable CO2 decomposition.