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As a promoter, Mn is widely used in Fischer–Tropsch synthesis (FTS) such as in the form of MnO, but few studies have focused on the effect of CoMn alloy on catalytic performance of FTS. Herein, a catalyst of CoMn alloy–loaded MnO is synthesized by a one‐step wet‐chemical method. The metallic Mn is formed through a segregation process from MnO support, which is induced by Co that is decomposed from Co‐contained precursor; then, the two metals form an alloy in the following growing process. In photothermocatalytic FTS, the optimized catalyst delivers good selectivity for light olefins (27.0% with the ratio of olefins to paraffins = 3.2); meanwhile, low CO2 selectivity (22.6%) ensures the effective use of carbon resources. Characterizations, including X‐ray photoelectron spectroscopy, high‐resolution transmission electron microscopy, and energy dispersive X‐ray mapping, reveal that the catalysts comprise CoMn alloy on MnO support. The formed CoMn alloy is the key for promoting the generation of light olefins. This study demonstrates a novel catalyst of CoMn alloy–loaded MnO for the production of light olefins via CO hydrogenation, which attains a value‐added solar‐to‐chemical energy conversion.

Solar-driven CO hydrogenation to light olefins holds great potential as a petroleum-independent process. Herein, a series of Fe5C2 loading on tunable N-doped carbon as photothermal catalysts are developed to achieve an efficient Fischer–Tropsch synthesis to olefin (FTO) reaction. Under light irradiation, the optimized catalyst delivers a selectivity of 55.3% for light olefins (CO2 free) at a CO conversion of 22.3%, showing 3.5 times the activity of pristine Fe5C2 catalyst. Experimental characterizations reveal electron transfer from the N atoms in support to the active phase of Fe5C2 to construct electron-rich active sites and therefore to boost the catalytic performance. N-concentration-dependent activity evaluation and density functional theory calculations ascertain that pyrrolic N plays a dominant role in promoting CO adsorption and activation. This study provides an alternative strategy of rational modulation of support to enhance solar-to-chemical conversion.

Recognizing the emergency of the global climate issue, the current fossil fuel‐based economic structure with massive carbon emission is urgent to be transformed. Catalytic conversion of CO x , as an emerging alternative technology to produce advanced chemicals and fuels, has received enormous attention. Particularly, photothermal CO x conversion, combining the advantages of high efficiency and low pollution, has shown the potential for the production of solar fuels and chemicals, and the progress of this field is accelerating. This review summarizes the fundamentals of photothermal catalysis as well as the state‐of‐the‐art advances of the photothermocatalytic CO x conversion in the three main parts that involve CO x hydrogenation, water–gas shift reaction, and CO2 reforming of CH4. Moreover, the challenges and perspectives are also briefly discussed, which proposes guidance for future investigation of photothermal C1 conversion and anthropogenic carbon cycle.

Photochemical conversion of CO2 into solar fuels is one of the promising strategies to reducing the CO2 emission and developing a sustainable carbon economy. For the more efficient utilization of solar spectrum, several approaches were adopted to pursue the visible-light-driven SrTiO3. Herein, oxygen vacancy was introduced over the commercial SrTiO3 (SrTiO3−x ) via the NaBH4 thermal treatment, to extend the light absorption and promote the CO2 adsorption over SrTiO3. Due to the mid-gap states resulted from the oxygen deficiency, combined with the intrinsic energy level of SrTiO3, the SrTiO3−x catalyst exhibited excellent CO productivity (4.1 μmolˑg−1ˑh−1) and stability from the CO2 photodissociation under the visible-light irradiation (λ > 400 nm). Then, surface alkalization over SrTiO3−x (OH-SrTiO3−x ) was carried out to further enhance the CO2 adsorption/activation over the surface base sites and provide the OH ions as hole acceptor, the surface alkali OH connected with Sr site of SrTiO3 could also weaken the Sr–O bonding thus facilitate the regeneration of surface oxygen vacancy under the light illumination, thus resulting in 1.5 times higher CO productivity additionally. This study demonstrates that the synergetic modulation of alkali OH and oxygen vacancy over SrTiO3 could largely promote the CO2 photodissociation activity.