Key Laboratory of Optoelectronic Materials Chemistry and Physics, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fuzhou, 350002, China.
Advanced Energy Science and Technology Guangdong Laboratory, 29 Sanxin North Road, Huizhou, Guangdong, 116023, China.
Angew Chem Int Ed Engl. 2023 Mar 13;62(12):e202300480. doi: 10.1002/anie.202300480. Epub 2023 Feb 14.
Introducing pores in single crystals creates a new type of porous materials that incorporate porosity and structural coherence. Herein, we use in situ transmission electron microscopy to disclose the porosity formation by converting KTiOPO (KTP) single crystals into porous single-crystalline (PSC) TiO monoliths in a solid-solid transformation. The isolated crystalline nuclei of TiO clusters with identical lattice orientation on KTP surface moves TiO /KTP interface toward mother phase for growing PSC TiO monoliths. The relative density in PSC TiO monoliths dominates porosity while the macroscopic dimensions remain unchanged in the transformation. The single-crystalline nature of porous architecture stabilizes oxygen vacancy to activate lattice oxygen while the three-dimensional percolation enhances species diffusion. PSC TiO monoliths with deposited Pt clusters show enhanced and stable catalytic CO oxidation in air at ∼75 °C for 200 hours of operation.
在单晶中引入孔道可产生一种新型多孔材料，兼具多孔性和结构连贯性。在此，我们通过在固态转变中将 KTiOPO（KTP）单晶转化为多孔单晶（PSC）TiO 整体，使用原位透射电子显微镜揭示了其孔道形成。KTP 表面上具有相同晶格取向的 TiO 团簇的孤立晶核向母相向 TiO/KTP 界面迁移，从而生长 PSC TiO 整体。在转变过程中，PSC TiO 整体的相对密度决定了其孔隙率，而宏观尺寸保持不变。多孔结构的单晶本质稳定了氧空位，从而激活晶格氧，而三维渗流则增强了物质扩散。沉积有 Pt 团簇的 PSC TiO 整体在空气中于约 75°C 下运行 200 小时时表现出增强且稳定的 CO 氧化催化活性。
