Well-defined cuprous oxide (Cu₂O) thin film electrodes were electrodeposited on indium-doped tin oxide (ITO) substrates from a slightly acidic Cu(II) acetate solution. The morphologies of Cu₂O film were tunable by altering the deposition potential, reaction time, solution temperature and the NaCl concentration. In particular, the Cu₂O morphologies evolved from dendritic branching to cube-like with the increasing of the NaCl concentration. A growth mechanism was proposed according to the experimental results. In addition, a photocurrent of 0.06 mA cm⁻², an open-circuit photovoltage (V_oc) of 0.38 V, and a significant energy conversation efficiency of 0.01% were obtained under 100 mW cm⁻² UV-visible illumination of the dendritic Cu₂O thin film.

Semiconductor/metal composite nanomaterials have been used as surface-enhanced Raman scattering (SERS) active substrates and have attracted increasing attention due to their widespread applications in both optical and material fields. Here, we report a facile strategy to prepare highly sensitive SERS substrates with excellent reproducibility and stability based on uniform and well-controlled Ag nanoparticle (NP) decorated Cu₂O nanoframes. Our strategy is a unique one-pot procedure. Simply, hollow Cu₂O/Ag composite nanoframes (Cu₂O/Ag CNFs) with tunable silver content have been successfully designed and constructed by reduction of Ag⁺ with sodium citrate in a 14 day old Cu₂O-containing mother solution, and then a second component (Ag) was directly deposited onto primary nanomaterials (Cu₂O nanoframes). There is an optimum amount of Ag NPs. When 0.40 mM AgNO₃ is used, the prepared Cu₂O/Ag CNFs show significantly improved SERS properties with an enhancement factor of ~10⁵. Furthermore, the enhancement mechanism, reproducibility and stability of Cu₂O/Ag CNFs are investigated in detail. The excellent properties of the prepared Cu₂O/Ag CNFs suggest that this substrate has a potential application in SERS detection.

The enhanced photoelectric performance of quantum dot sensitized solar cells via hydrogenated TiO₂ is proposed. The best energy conversion efficiency is 1.5 times higher than cells without hydrogen treatment. We demonstrated that introducing oxygen vacancies by hydrogenation is an effective and feasible method for enhanced photoelectric performance.