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Ag and Au nanocrystals, is able to increase the temperature of nanocrystals.[8–10] However, most of efficient catalysts for CO2 hydrogenation do not possess photothermal effect.[11] If these catalysts can also take advantage of photothermal effect, it is promising to realize CO2 hydrogenation at relatively low temperature (≤ 100 C). Herein, we achieved localized heating under light irradiation to reduce the reaction temperature of CO2 hydrogenation by encapsulating Pt nanocubes and Au nanocages into a zeolitic imidazolate framework (ZIF-8) to form a hybrid structure (Au&Pt@ ZIF). Specifically, Pt nanocubes serve as a catalyst toward CO2 hydrogenation. As photothermal nanocrystals, Au nanocages with strong extinction in the near-infrared region could efficiently transform light to thermal energy. Notably, metal–organic frameworks (MOFs) function as “heat insulators” to prevent heat from dispersing in solution. Under light irradiation, the heat generated from Au nanocages was confined in MOFs to form a localized high-temperature region, thereby significantly improving the catalytic activity of Pt nanocubes. The entire process is illustrated in Figure 1A. In comparison, when Au nanocages were injected into aqueous solution with only Pt nanocubes immobilized in ZIF-8 (denoted as Pt@ ZIF+ Au), the temperature of Pt nanocubes was barely raised (Figure 1B). The reason is that the heat generated by light-to-heat conversion on Au nanocages was mainly dispersed in solution rather than localized in the catalytic system. When the reaction was conducted under light irradiation at 150 C, the turnover frequency (TOF) number for Au&Pt@ ZIF reached …