Solar vapor generation is a facile and an efficient way for solar energy harvesting, which is applied to address the issue of fresh water extraction from sewage or brine. Several solar vapor generation devices have been developed in the past few years, but the low evaporation rate still remains as a challenge. In this work, a novel double-layer solar vapor generation device, named as Ag-PSS-AG/AG device, is reported. This device is based on the hierarchical composition of silver nanoparticles (Ag NPs) and poly (sodiump-styrenesulfonate) (PSS) decorated agarose gel (AG). The device reveals a synergetic effect of the two layers with high light-harvesting and watertransfer performance, respectively, leading to an ultrahigh vapor generation rate of 2.10 kg m −2 h −1 with a solar thermal efficiency of 92.8% under 1 sun illumination. This high evaporation rate is mainly owing to the powerful light-thermal conversion of Ag NPs as well as the outstanding water transfer capability of agarose hydrogel. Consequently, this device can be directly used for the purification of sewage and muddy water. It is also promising for applications in separation, humidity management, and others.NPs embedded in AG skeleton ensures the adequate transfer and full utilization of the converted heat energy. Therefore, the Ag-PSS-AG/AG device exhibits an ultrahigh vapor generation rate of 2.10 kg m −2 h −1 with a solar thermal efficiency of 92.8% under 1 sun illumination.

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In this work, CO2 hydrogenation over In2O3-supported rhenium (Re) catalysts was found to be highly size-dependent. When the Re loading was less than 1 wt %, the strong interaction between Re and In2O3 caused atomically dispersed Re species with a positive charge, resulting in high activity for CO2 hydrogenation to methanol with enhanced stability at elevated temperatures. The space–time yield of methanol over the 1 wt % Re/In2O3 catalyst reached 0.54 gMeOH gcat –1 h–1 with a methanol selectivity of 72.1% at 5 MPa and 573 K. With increasing Re loading, the In2O3 supported Re catalysts become more favored for CO2 methanation. Under the same experimental conditions, the methane selectivity is close to 100.0% over the 10 wt % Re/In2O3 catalyst. Catalyst characterizations and density functional theoretical (DFT) calculations further confirm that the size of the Re/In2O3 catalyst has a significant effect on hydrogen activation and the selectivity of the CO2 hydrogenation reaction. Due to the strong Re–In2O3 interaction, the atomically dispersed Re in the In2O3 surface lattice not only stabilizes oxygen vacancies but also results in Hδ+ formation upon hydrogen adsorption. This significantly promotes methanol synthesis from CO2 hydrogenation. Meanwhile, the 10 wt % Re/In2O3 catalyst with supported Re nanoclusters induces H δ‑ formation, which eventually leads to more methane production. The present study demonstrates the atomically dispersed Re/In2O3 catalyst is promising for CO2 hydrogenation to methanol.