Photocatalytic CO₂ conversion is vital technology to realize global carbon neutrality and generate future energy supplies. This review proposes fundamentals, challenges, strategies, and prospects for photocatalytic CO₂ conversion research.

Controlled shifting of the CO ₂ reduction product from C ₁ to C ₂ hydrocarbons obtained with graphene wrapped blue titania under solar light.

In the current work, we demonstrate that single Cu atoms, which are site-specifically stabilized in Ti vacancy of TiO₂, interact with surrounding TiO₂ and control the overall electronic properties (reducibility and defect formation) of TiO₂.

Photocatalytic CO₂ conversion to fuel offers an exciting prospect for solar energy storage and transportation thereof. Several photocatalysts have been employed for CO₂ photoreduction; the challenge of realizing a low-cost, readily synthesized photocorrosion-stable photocatalytic material that absorbs and successfully utilizes a broad portion of the solar spectrum energy is as yet unmet. Herein, a mesoporous p-type/n-type heterojunction material, Cu_xO–TiO₂ (x = 1, 2), is synthesized via annealing of Cu/Cu₂O nanocomposites mixed with a TiO₂ precursor (TiCl₄). Such an experimental approach in which two materials of diverse bandgaps are coupled provides a simultaneous opportunity for greater light absorption and rapid charge separation because of the intrinsic p–n heterojunction nature of the material. As detailed herein, this heterostructured photocatalyst demonstrates an improved photocatalytic activity. With the CO₂ reduction of our optimal sample (augmented light absorption, efficacious charge separation, and mesoporosity) that utilizes no metal cocatalysts, a remarkable methane yield of 221.63 ppm·g⁻¹·h⁻¹ is achieved.

Cu–Pt bimetallic nanoparticles deposited over blue titania exhibiting record photoconversion efficiency for CO ₂ photoreduction into fuels.