Piezoelectric performance enhancement of ZnO flexible nanogenerator by a NiO–ZnO p–n junction formation. (May 2015)

• Record Type: Journal Article
• Authors: Yin, Bing; Qiu, Yu; Zhang, Heqiu; Lei, Jixue; Chang, Yue; Ji, Jiuyu; Luo, Yingmin; Zhao, Yu; Hu, Lizhong
• Is Part Of: Nano energy. Volume 14(2015:May)
• Page Start: 95
• Page End: 101
• Publication Date: 2015-05
• Subjects: Piezoelectric nanogenerator -- Zinc oxide -- p–n junction; Nanoscience -- Periodicals; Nanotechnology -- Periodicals; Nanostructured materials -- Periodicals; Power resources -- Technological innovations -- Periodicals; Nanoscience; Nanostructured materials; Nanotechnology; Power resources -- Technological innovations; Periodicals; 621.042
• DOI: 10.1016/j.nanoen.2015.01.032
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: Enhancing the output power of a nanogenerator is essential in applications as a sustainable power source for wireless sensors and personal electronic devices. As one possible solution, NiO–ZnO heterojunction is used for piezoelectric performance enhancement via both suppressing the screening effect in the ZnO film and forming a reliable p–n junction at the interfaces instead of the Schottky barriers. From pristine ZnO nanogenerators, alternating current (AC)-type output signal was observed, while from NiO–ZnO nanogenerators, direct current (DC)-type output signal was surprisingly obtained under the same vertical compressive force. By forming a NiO–ZnO heterostructure, the DC output voltage was up to 430 mV and the maximum output current density was of 40 nA cm −2, which are approximately 21-fold higher voltage and 13 times larger current density by comparison to the pristine ZnO nanogenerators. The results provide a simple, low-cost and effective approach for enhancing the piezoelectric performance. Graphical abstract: Piezoelectric performance enhancement of ZnO flexible nanogenerator by a NiO–ZnO p–n junction formation. Highlights: NiO is used to improve the piezoelectric performance by forming a NiO–ZnO p–n junction. The energy harvesting device uses a semiconductor p–n junction, rather than a metal–semiconductor Schottky barrier. The NiO–ZnO p–n junction reduces the excess electrons in the ZnO film. The NiO–ZnO p–n junction can enhance the output signs by reducing the capacitance of the device.