1. Preparation of nanostructured Cu and Cu-based catalysts for photocatalytic, electrocatalytic and photoelectrocatalytic carbon dioxide reduction; 2. Non-noble metal catalysts for efficient water electrolysis; 3. Energy storage materials and devices such as aqueous batteries and supercapacitors; 4. Preparation of nanostructured semiconductors for photocatalytic degradation of organic pollutants; 5. DFT calculation about the band structure of semiconductors and catalytic mechanism.