Facile synthesis of ZnO/PdSe2 core-shell heterojunction for efficient photodetector application.

ZnO/PdSe 2 core-shell heterojunction nanorod arrays exhibit higher photocurrent (≈0.75 mA cm−2) and faster response (T off/ZnO@PdSe2 =4.5 ms, T on/ZnO@PdSe2 =4.5 ms) than most of reported commercial ZnO and ZnO composite nanomaterials. [Display omitted] • ZnO/PdSe 2 core-shell HNAs were synthesized by a low temperature selenization method for the first time. • ZnO/PdSe 2 core-shell HNAs possess stable structures and superb active interfaces. • Ultrafast response and high photocurrent density were achieved. • A more profound mechanism for the ZnO/PdSe 2 photoelectrochemical (PEC) reaction was proposed. Palladium diselenide (PdSe 2), a group-10 transition metal dichalcogenide with great optoelectronic and electrical properties due to unique structure, has gained increasing attention in the scientific community. Herein, we demonstrate an effective strategy to synthesis of ZnO/PdSe 2 core–shell heterojunction nanorod arrays (HNAs) through a simple two-step method for the first time. A Pd film was deposited on ZnO NAs by an electron beam evaporation method at first. Then, the selenization process was completed by a chemical vapor deposition (CVD) method. Furthermore, the photoelectric performances of electrodes based on ZnO NAs, PdSe 2 film and ZnO/PdSe 2 core–shell HNAs were investigated, respectively. The ZnO/PdSe 2 core–shell HNA represents better responsitivity with higher photocurrent density (1.3 mA cm−2) comparing to the ZnO NA (0.03 mA cm−2), indicating that the ZnO/PdSe 2 samples are more suitable for photoelectric devices. Besides, photoelectric performance of this work is better than most of reported commercial ZnO and ZnO composite nanomaterials. [ABSTRACT FROM AUTHOR]