Hollow Cu–TiO2/C nanospheres derived from a Ti precursor encapsulated MOF coating for efficient photocatalytic hydrogen evolution

Abstract

Here we report an effective approach for preparing hollow carbon nanospheres with Cu–TiO₂ from a Ti precursor encapsulated surface mounted MOF (SURMOF) coating. Firstly a core–shell structured Cu-based SURMOF HKUST-1 on SiO₂ nanospheres (SiO₂@HKUST-1) with a thin and homogeneous shell coating has been prepared by a liquid-phase epitaxial layer by layer immersion method. Then the uniform SiO₂@HKUST-1 nanospheres were loaded with a Ti precursor Ti(O-ipr)₄, followed by calcination at 800 °C; hollow carbon nanospheres with Cu–TiO₂ (Cu–TiO₂/C) could be obtained after etching SiO₂ nanosphere templates. As a result of their unique structure, such hollow, thin, uniform and homogeneous Cu–TiO₂/C nanospheres had efficient photocatalytic H₂ production and excellent recyclability under simulated sunlight irradiation. The method developed here provides a new approach for the preparation of hollow hybrid carbon nanospheres with various applications.