In-situ Constructing AlTiZn/CN Heterojunction Via Memory Effect for Effective Degradation of Naphthalene under UV Irradiation

Improving active sites through thoughtful design of material structure is an effective approach to boost activation efficiency and degradation performance. In this study, a series of x/AlTiZn/CN heterojunctions were successfully fabricated via the in-situ self-assembly of x/AlTiZnO and g-C3N4, utilizing the memory effect of layered double hydroxides (LDH). AlTiZnO was reverted to AlTiZn-LDH framework in deionized water, which provided OH--metal and active sites on the solid surface through memory effect during restoration. Systematic characterizations confirmed that 20/AlTiZn/CN heterojunction, restored from in-situ self-assembly of 20/AlTiZnO and g-C3N4, is a characteristic of mesoporous material with larger specific surface area. Then, photoelectric performance tests of naphthalene (NPT) degradation obviously manifested that a significant enhancement in photocatalytic performance of x/AlTiZn/CN heterojunction. This improvement primarily attributed to the compact contact interface and the synergistic effect between g-C3N4 and AlTiZn-LDH restored from AlTiZn-LDO, which accelerated the charge transfer process at the interface. Consequently, the degradation efficiencies of 20/AlTiZn/CN were 3.5, 1.27 and 2.60 times higher than those of 20/AlTiZn-LDH, 20/AlTiZn-LDH/CN and g-C3N4, respectively. Moreover, photocatalytic degradation of NPT over 20/AlTiZn-LDH/CN followed quasi-first-order kinetics. Finally, the scavenging experiment, ESR, and degradation pathways analysis indicate that the highly efficient NPT photodegradation over 20/AlTiZn/CN is the synergistic results of memory effect and various active substance, such as ·O2−, ·OH and h+. This study exploits a cost-effective, environmentally friendly photocatalyst and provides valuable insights into the photocatalysis degradation of NPT.