To date, infrared (IR) light constituting almost 50% of the solar energy has never been utilized, owing to an insurmountable contradiction between IR light utilization and CO₂ photoreduction. To break through this limitation, we designed an ultrathin intermediate-band semiconductor, and hence first realized IR-driven CO₂ overall splitting on a single material without using any sacrificial reductants. Taking the synthetic ultrathin cubic-WO₃ layers as an example, theoretical calculations disclose that the created oxygen vacancies reaching a critical density results in an intermediate band, verified by synchrotron-radiation valence-band spectra, photoluminescence spectra, UV-vis-NIR spectra, and synchrotron-radiation IR reflectance spectra. As a result, the oxygen-deficient WO₃ atomic layers display IR-driven CO₂ overall splitting to CO and O₂, while their catalytic activity proceeds without deactivation even after 3 days. Also, the higher oxygen vacancy concentration favors CO₂ adsorption and activation into COOH* radical, affirmed by CO₂ temperature-programmed desorption spectra and in situ FTIR spectra, hence guaranteeing increased CO and O₂ formation rates.

迄今为止，由于IR光的利用与CO _2的光还原之间存在无法克服的矛盾，所以几乎没有利用构成太阳能的近50％的红外（IR）光。为了克服此限制，我们设计了超薄中带半导体，因此首先在不使用任何牺牲还原剂的情况下，在单一材料上实现了红外驱动的CO ₂整体分解。取合成的超薄立方WO ₃以计算层为例，理论计算表明，所产生的氧空位达到临界密度会产生中间带，并通过同步辐射价带光谱，光致发光光谱，UV-vis-NIR光谱和同步辐射IR反射光谱进行验证。结果，缺氧的WO ₃原子层显示出IR驱动的CO ₂整体分裂成CO和O ₂，而它们的催化活性甚至在3天后仍未失活。同样，较高的氧空位浓度有利于CO ₂吸附和活化成COOH *自由基，这是由CO ₂温度编程的解吸光谱和原位证实的FTIR光谱，从而保证增加的CO和O ₂形成速率。