Miri, AshkanAshkanMiriXiao, YonghaoYonghaoXiaoChan, Wei XinWei XinChanGuan, HaoranHaoranGuanVenkatesan, PrashanthPrashanthVenkatesanSoo, Han SenHan SenSooYANG-HSIN SHIH2026-02-252026-02-252026-0422132929https://www.scopus.com/pages/publications/105029187910https://scholars.lib.ntu.edu.tw/handle/123456789/735979Article number 121441The photocatalytic activity of g-C3N4 is hindered by the rapid recombination of photogenerated charge carriers. To improve the photocatalytic performance, various strategies have been implemented, including the development of novel hybrid nanocomposites utilizing two semiconductor materials. Herein, we present novel visible-light-driven 3D/2D heterojunction photocatalysts composed of 2D g-C3N4 nanosheets and a lead-free BA2CsAg0.95Na0.05BiBr7 perovskite, which was re-structured during the synthesis to form a 3D Cs2Ag0.95Na0.05BiBr6 perovskite. The photocatalytic efficiency of the 3D/2D Cs2Ag0.95Na0.05BiBr6/g-C3N4 was assessed through the photodegradation of bisphenol A (BPA). The Cs2Ag0.95Na0.05BiBr6/g-C3N4 exhibited a BPA degradation rate of 4.4 × 10−2.min−1, which was 2.3 and 4.4 times higher than that of bulk-g-C3N4 and pure Cs2Ag0.95Na0.05BiBr6, respectively. The enhanced activity was attributed to the synergistic effects of Cs2Ag0.95Na0.05BiBr7/g-C3N4, characterized by strong internal interaction and a 3D/2D structure, resulting in a reduced recombination rate of the photogenerated electrons and holes. Scavenger tests and EPR analyses indicated that ●O2¯,1O2, and h + were the primary radicals involved in the BPA degradation. A plausible photocatalytic mechanism consistent with an S-scheme heterojunction was proposed. The findings of this study demonstrated that the fabrication of a 3D/2D heterojunction is an effective strategy to addressing the limitations of conventional photocatalysts, thereby enhancing their performances in the context of more sustainable photocatalysis and green chemistry.false3D perovskiteBPAG-C3N4Photocatalytic reactionsWater treatmentjournal article10.1016/j.jece.2026.1214412-s2.0-105029187910