The photothermal catalysis CO₂ reduction is considered as an attractive means to solve the greenhouse effect and energy crisis. However, due to the slow charge transfer kinetics on the surface of the catalyst and sparse adsorption active site, the CO₂ adsorption rate is low and the carrier life is short. So, the catalytic performance is limited. Here, a core–shell similar structure catalyst for photothermal CO₂ reduction was constructed by growing of Cd_0.3Zn_0.7S (CZS) nanospheres on the surface of sulfur defect rich Cd₂In₂S₅ (CIS) ultra-thin nanosheets, and which was coordinated by the interfacial chemical bond and the interfacial internal electric field. The Cd-S chemical bond became a direct channel to accelerate the transfer of electrons from the conduction band of CZS to the conduction band of CIS, leading to higher surface charge localization of CIS/CZS, and encapsulating the active site of hydrogen evolution of CZS. The core–shell similar structure was favorable for the spatial separation of photogenerated charges. The production of *HCO₃^– and *COOH intermediates on the CIS/CZS surface has been proved to be crucial for CO₂ adsorption and CO generation by in situ Fourier transform infrared spectroscopy. The charge transfer mechanism of Type Ⅱ between CIS and CZS was proved by density functional theory calculation and in situ X-ray photoelectron spectroscopy. The CO yield of the optimized CIS/CZS heterojunction was 64.3 μmol·h⁻¹·g⁻¹, which was about 31.3 times that of pure CZS. This study provided a new idea for accelerating charge transfer dynamics and inhibiting competition reaction to promote the conversion of solar energy to fuel.

光热催化CO ₂还原被认为是解决温室效应和能源危机的一种有吸引力的手段。但由于催化剂表面电荷转移动力学缓慢、吸附活性位点稀疏，导致CO ₂吸附速率低、载体寿命短。因此，催化性能受到限制。_{这里，通过在富含硫缺陷的Cd 2} In ₂ S ₅ (CIS)超薄纳米片表面生长Cd _0.3 Zn _0.7 S (CZS)纳米球，构建了用于光热CO ₂还原的核壳相似结构催化剂，并且它是由界面化学键和界面内电场协调作用的。Cd-S化学键成为加速电子从CZS导带转移到CIS导带的直接通道，导致CIS/CZS更高的表面电荷局域化，并封装了CZS析氢活性位点。核壳相似的结构有利于光生电荷的空间分离。原位傅里叶变换红外光谱证明，CIS/CZS 表面*HCO ₃ ^{-和*COOH 中间体的产生对于CO} ₂吸附和CO 生成至关重要。通过密度泛函理论计算和原位X射线光电子能谱证明了CIS和CZS之间Type Ⅱ的电荷转移机制。优化后的CIS/CZS异质结的CO产率为64.3 μmol·h ^-1 ·g ^-1，约为纯CZS的31.3倍。该研究为加速电荷转移动力学和抑制竞争反应以促进太阳能向燃料的转化提供了新思路。