Metal oxide mesocrystals (MCs) and mesoporous single crystals (MSCs) exhibit superior carrier transport ability, high specific surface area, shortened photo-carrier diffusion lengths to interfaces and enhanced absorbance of the incident sunlight. These advanced features make metal oxide MCs and MSCs be a promising candidate material in photocatalysis, photoelectrocatalysis, dye sensitized solar cells (DSSCs) and perovskite solar cells (PSCs). Recently, remarkable advances of applying metal oxide MCs and MSCs in these areas have been achieved. Therefore, it is extremely important to deeply understand the influence of the unique properties of metal oxide MCs and MSCs on solar energy conversion systems. Herein, we presented a brief introduction on the synthesis and carrier transfer behavior of metal oxide MCs and MSCs. Then, the rational structure design and modification of metal oxide MCs and MSCs for photocatalysis, photoelectrocatalysis, DSSCs and PSCs are systematically discussed. Finally, the perspectives on extending the application of metal oxide MCs and MSCs are addressed.

金属氧化物介晶（MCs）和介孔单晶（MSCs）表现出优异的载流子传输能力，高比表面积，缩短了界面的光载流子扩散长度并增强了入射太阳光的吸收率。这些先进的功能使金属氧化物MC和MSC成为光催化，光电催化，染料敏化太阳能电池（DSSC）和钙钛矿太阳能电池（PSC）的有希望的候选材料。最近，在这些领域中应用金属氧化物MC和MSC取得了显着进展。因此，深刻理解金属氧化物MC和MSC的独特性能对太阳能转换系统的影响极为重要。本文中，我们简要介绍了金属氧化物MC和MSC的合成和载流子迁移行为。然后，系统地讨论了用于光催化，光电催化，DSSC和PSC的金属氧化物MC和MSC的合理结构设计和改性。最后，讨论了扩展金属氧化物MC和MSC应用的观点。