Climate change is in full swing and will continue unabated as long as CO2 emissions continue. One possible solution is to return CO2 to the energy cycle: CO2 could be processed with water into methanol, a fuel that can be easily transported and stored. However, the reaction, which is reminiscent of a partial process of photosynthesis, requires energy and catalysts. Developing light-active photocatalysts from abundant, easily obtained materials would enable green, climate-neutral solar fuels.