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钙钛矿相SrTiO3在太阳能电池、光催化、燃料电池,超导等领域均有广泛应用,这些应用均与其晶体质量、形貌、暴露晶面和光学吸收等特性息息相关.本文通过微弧氧化-水热两步法原位制备了两种典型形貌的SrTiO3纳米晶.结果表明,随着微弧氧化电解液锶源浓度的降低,SrTiO3形貌从立方块状转变为超薄片状.进一步分析表明,所得的SrTiO3立方块和Sr1-δTiO3纳米片均为结晶质量良好的单晶体,通过分析两种形貌样品的紫外-可见漫反射光谱,发现Sr1-δTiO3纳米片相对于SrTiO3立方块,具有明显的尺寸效应诱导的光学吸收蓝移特性.最后,本研究提出了SrTiO3的原位生长及形貌演变机制.“,”As a perovskite family member, SrTiO3 shows significant applications in the fields of solar cells, photocatalysis, fuel cells and superconducting as a dependence of its crystallinity, morphology, crystal facet and optical properties. In this work, we reported an in-situ synthetic approach of SrTiO3 nanostructures with modified morphology and tunable optical absorption properties based on conventional plasma electrolytic oxidation (PEO) associated with hydrothermal method. The morphology of SrTiO3 nanostructures can be selectively modified from microcubes with smooth facets to ultrathin nanosheets by controlling the concentration of Sr source during PEO process. It is found that both SrTiO3 microcubes and Sr1–δTiO3 nanosheets are well-crystallized single crystals. UV-Vis diffuse reactance spectrum (DRS) measurement reveals that Sr1–δTiO3 nanosheets with thin thickness show obvious blue-shift of absorption edge in comparison with SrTiO3 microcubes due to the size effect. Finally, the morphology evolution and nucleation mechanism of SrTiO3 nanostructures in-situ grown on PEO film is discussed.