A review on fabricating heterostructures from layered double hydroxides for enhanced photocatalytic activities

There is growing interest in photocatalytic applications of layered double hydroxides (LDHs) because of their unique two-dimensional (2D) lamellar structural features and optical properties. This review initially reveals that adjustable components of LDHs control their electronic structures. On the basis of this characteristic, LDHs have emerged as very promising candidates for constructing highly efficient photocatalysts. As a result, 2D LDH-containing heterostructures were prepared according to two strategies: one generated the desired structural configurations, including horizontally and vertically stacked hierarchical heterostructures, and the other comprised band gap engineering with staggered-gap heterojunctions. The heterojunctions that were obtained displayed enhanced photocatalytic activities because of the facilitated transfer of photogenerated carriers and their prolonged lifetime and extended light-response range. Thus, LDH-containing heterostructures exhibited better photocatalytic effects than their individual components in the same applications. Finally, this review provides a brief perspective on the future of the fabrication of LDH-containing heterostructures.