Construction of Geopolymer Zeolite‐Graphene/Carbon Nanotube Interface for Strong Metal−Support Interaction (SMSI) Effect to Achieve Efficient Solar Evaporation and Highly Selective Synergistic Catalytic Reduction of CO ₂

ABSTRACT The challenges of CO ₂ energy conversion and the shortage of clean water resources have become critical global issues. Photocatalytic CO ₂ reduction and solar‐driven evaporation technology are promising solutions to address these challenges. In this study, a dual‐functional biomimetic, mushroom‐shaped 3D geopolymer zeolite‐nickel@carbon nanotube‐graphene composite material (3DGZ‐Ni@CNTG) solar evaporator was developed, which integrates high photothermal evaporation with excellent CO ₂ photocatalytic reduction performance. It precisely combines the zeolite water transport layer, carbon nanotube‐graphene (CNTG) photothermal layer, and metallic nickel catalyst, with each component's functions working synergistically. Under 1‐sun intensity, the evaporator achieves an evaporation efficiency of 151% and an evaporation rate of 2.84 kg·m ⁻² ·h ⁻¹ , significantly outperforming similar devices. Additionally, it maintains high operational stability over 14 days of continuous evaporation in simulated seawater salinity without any salt accumulation on the surface. Moreover, the 3DGZ‐Ni@CNTG material efficiently photocatalyzes CO ₂ reduction to produce CO at relatively low temperatures, with high selectivity. The H ₂ O (water vapor) generated by the solar‐driven photothermal evaporation process, along with CO produced from CO ₂ reduction, can serve as key components of the water‐gas shift reaction (mainly CO and H ₂ O), a key process in the synthetic chemical industry. This provides a new idea for the integrated use of “solar energy‐freshwater‐carbon‐based chemicals,” creating a closed‐loop material cycle.