The layered titanium oxide is a useful and unique precursor for the facile and rapid preparation of the peroxide layered titanium oxide H_1.07Ti_1.73O₄·nH₂O (HTO) crystal with enhanced visible light photoactivity. The H₂O₂ molecules as peroxide chemicals rapidly enter into the interlayers of HTO crystal, and coordinate with Ti within TiO₆ octahedron to form a mass of Ti-O-O coordination bond in the interlayers. The introduction of these Ti-O-O coordination bonds result in lowering the band gap of HTO, and promoting the separation efficiency of the photo induced electron–hole pairs. Meanwhile, the photocatalytic investigation indicates that such peroxide HTO crystal has the enhanced photocatalytic performance for RhB degradation and water splitting to generate oxygen under visible light irradiating.

Bismuth chalcogenide iodides Bi ₁₃ S ₁₈ I ₂ and BiSI were synthesized and characterized as light absorbers for solar cells.

A CdS/MnS p–n heterojunction is prepared. The H₂ production rate is 5.92 mmol g⁻¹ h⁻¹ with the apparent quantum efficiency of 5.63% at 420 nm, which is 10.57 times and 49.33 times higher than that of CdS nanorods and MnS, respectively.

A good-performance and low-cost electrocatalyst Ni–rGO/CeO ₂ has been achieved due to the increased oxygen vacancies and active sites brought about by the synergistic effect of rGO decoration and Ni doping.

Bismuth chalcohalides of ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{X}_2$ (X = $\mathrm{Cl},\mathrm{Br},\mathrm{I}$) are solvothermally synthesized and systematically characterized as a light absorber for photovoltaics. Rietveld refinements reveal that ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{X}_2$ compounds adopt the same hexagonal structure with space group P3 and a chemical composition of $({\mathrm{Bi}}^{3+}{)}_{12}({\mathrm{Bi}}_2^{4+}{)}_{0.5}({\mathrm{S}}^{2-}{)}_{18}(X^{-}{)}_2$, where a triangular tunnel is constructed from [${\mathrm{Bi}}_4{\mathrm{S}}_6$]-ribbon spokes in the c-axial direction, $X^{-}$ is located in the tunnel sites, and Bi(II) dimers of (${\mathrm{Bi}}_2^{4+}$) are located at the hexagonal center. The photoelectric behavior is investigated using ultraviolet-to-visible-to-near-infrared (UV-vis-NIR) absorption spectroscopy, ultraviolet photoelectron spectroscopy, x-ray photoelectron spectroscopy, Mott-Schottky plots, and conductivity measurements. The ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{X}_2$ compounds are indirect n-type semiconductors with narrow band gaps of 0.76, 0.80, and 0.81 eV for ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{Cl}}_2$, ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{Br}}_2$, and ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{I}}_2$, respectively, and exhibit strong light absorbance over a wide wavelength range from UV to NIR. A facile physical vapor deposition approach is developed for the fabrication of a homogeneous ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{X}_2$ thin film to study the photovoltaic performances. Solar cells with the architecture fluorine-doped tin oxide/${\mathrm{Ti}\mathrm{O}}_2$/${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{X}_2$/(${\mathrm{I}}_3^{-}/{\mathrm{I}}^{-}$ redox couple)/$\mathrm{Pt}$ demonstrate power conversion efficiencies of 0.91, 1.12, and 0.75% for ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{Cl}}_2$, ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{Br}}_2$, and ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{I}}_2$, respectively. The highest cell performance of ${\mathrm{Bi}}_{13}{\mathrm{S}}_{18}{\mathrm{Br}}_2$ can be attributed to its higher light-absorption ability.