Riri Jonuarti, Maulana Reizqy Anugrah, Rahmat Hidayat, Yenni Kurniawati, Wilson Agerico Diño, Anjar Anggraini Harumningtyas
This study reports the engineering of core@shell Fe2O3@CuO nanocubes synthesized via a two-step hydrothermal method and their evaluation as Fe2O3-based heterostructured photocatalysts. Fe2O3 nanocubes were used as the core material, while CuO was incorporated as the shell component to construct an interfacial oxide heterostructure. SEM observations showed that the nanocubic morphology was retained after CuO incorporation, with the average cube-edge size increasing from approximately 22.93 nm for Fe2O3 to 25.25 nm for Fe2O3@CuO. XRF analysis indicated that the Fe2O3@CuO sample contained approximately 66 wt% Fe2O3 and 26 wt% CuO, while XRD confirmed the coexistence of hematite α-Fe2O3 and monoclinic CuO phases. UV–vis analysis showed that CuO incorporation modified the optical response, with the estimated optical band gap changing from 0.88 eV for Fe2O3 to 1.11 eV for Fe2O3@CuO. Photocatalytic tests using methylene blue degradation demonstrated that Fe2O3@CuO achieved 72.72% degradation after 120 min of UV irradiation, compared with 37.00% for pristine Fe2O3. The apparent pseudo-first-order rate constant also increased from 0.0024 min−1 for Fe2O3 to 0.0045 min−1 for Fe2O3@CuO. XPS analysis further indicated surface chemical modification after CuO incorporation, including a weak Cu-related signal and changes in Fe 2p and O 1 s spectral features. Density functional theory calculations revealed that the Cu↑O↓ configuration adsorbed on the hollow site of the Fe2O3 surface forms the more favorable interfacial arrangement, showing stronger orbital interaction, larger bond-order contribution, and more pronounced local charge polarization than the bridge-site configuration. These combined experimental and theoretical results indicate that CuO incorporation enhances the photocatalytic behavior Fe2O3 nanocubes by modifying the surface chemistry, strengthening interfacial bonding, and promoting charge redistribution across the Fe2O3–CuO interface. © 2026 Elsevier B.V.
Department of Physics, Universitas Negeri Padang, Jalam Prof. Dr. Hamka Air Tawar Barat, Padang, 25171, Indonesia; Department of Statistics, Univeristas Negeri Padang, Jalan Prof. Dr. Hamka Air Tawar Barat, Padang, 25171, Indonesia; Department of Applied Physics, Grad. School of Engineering, The University of Osaka, 2-1 Yamadaoka, Suita, Osaka, 565-0871, Japan; Research Center for Food Technology and Processing, National Research and Innovation Agency (BRIN), Jalan Jogja-Wonosari km 31.5 Gading, Playen, Gunungkidul, Yogyakarta, Indonesia
