Catalysis

Adsorption

Photochemistry

Metallurgy

Materials science

Absorption edge

Nuclear physics

Single crystal

Semiconductor

Band gap

Physical chemistry

Visible spectrum

Physics

Organic chemistry

Irradiation

Metal-organic framework

Crystallography

Chemistry

Photocatalysis

Optoelectronics

Cadmium

Advanced Materials

The development of new metal–organic frameworks (MOFs) with dual functions of both water reduction and oxidation under visible-light irradiation is highly desirable for promising solar water splitting, but is not yet reported. Herein, a cadmium-based MOF (denoted as “Cd-TBAPy”) single crystal with a 2D layered framework by employing 1,3,6,8-tetrakis(p-benzoic acid)pyrene (H4TBAPy) as an organic linker is reported, which exhibits good visible-light absorption with edge of ≈600 nm. The Mott–Schottky (M–S) measurement and UV–vis analysis integrally reveal that the Cd-TBAPy is an n-type semiconductor with a bandgap of ≈2.15 eV whose conduction and valence band are estimated to be −0.05 and 2.10 eV, respectively. Together with loading of Pt or CoPi cocatalyst, the Cd-TBAPy is active for both water reduction and oxidation in the presence of scavengers under visible-light irradiation. Especially, the optimized apparent quantum efficiency for O2 evolution reaches 5.6% at 420 nm, much higher than that of previous MOF-based photocatalysts reported so far. This is thought to be the first MOF that functions as a photocatalyst for both water reduction and oxidation under visible light, demonstrating the intriguing future of MOF materials in solar-to-chemical energy conversion.

Visible-Light-Responsive 2D Cadmium-Organic Framework Single Crystals with Dual Functions of Water Reduction and Oxidation