Nanoengineering Construction of Cu₂O Nanowire Arrays Encapsulated with g‑C₃N₄ as 3D Spatial Reticulation All-Solid-State Direct Z‑Scheme Photocatalysts for Photocatalytic Reduction of Carbon Dioxide

Artificial photosynthesis is a promising strategy to convert carbon dioxide into value-added fuels and chemicals with efficient sunlight utilization. Nevertheless, there are many shortcomings, such as high photogenerated electron–hole recombination rate and poor light stability, that hinder the further development of artificial photosynthesis. Thus, inspired by the natural photosynthesis of green plants, a 3D spatial reticulation all-solid-state artificial direct Z-scheme photocatalyst is manufactured to solve the above problems by using a graphite phase carbon nitride (g-C₃N₄) shell encapsulating Cu₂O nanowire arrays/Cu mesh (g-C₃N₄/Cu₂O NAs/CM). Consequently, the CH₃OH formation rate and the selectivity of g-C₃N₄/Cu₂O NAs reached 22.6 ppm cm^–2 h^–1 and 94.9% under solar light irradiation, respectively. More importantly, the material retained 94.7% of its primary catalytic activity after 60 h test (ten reaction cycles). It is attributed to the protective g-C₃N₄ layer and the synergetic effect between interface carrier separation modulation and relatively short radial transmission channel design. This strategy provides unique insights into the design and preparation of efficient practical photocatalysts for energy synthesis.