Interface engineering on p-CuI/n-ZnO heterojunction for enhancing piezoelectric and piezo-phototronic performance. (August 2016)

• Record Type: Journal Article
• Authors: Liu, Caihong; Peng, Mingzeng; Yu, Aifang; Liu, Jingyu; Song, Ming; Zhang, Yang; Zhai, Junyi
• Is Part Of: Nano energy. Volume 26(2016:Aug.)
• Page Start: 417
• Page End: 424
• Publication Date: 2016-08
• Subjects: Interface engineering -- Energy harvesting -- Piezocharges -- Piezo-phototronic effect -- UV photosensing; 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.2016.05.041
• Languages: English
• ISSNs: 2211-2855

Abstract

Abstract: The enhanced piezoelectric and piezo-phototronic performance of ZnO-based thin film devices has been achieved by interface engineering. The piezoelectric performance of ZnO thin film is significantly boosted due to the formation of CuI/ZnO heterojunction, which effectively reduce the unfavorable piezopotential screening effect induced by free electrons in n-type ZnO. Furthermore, taking the advantage of the piezo-phototronic effect, the mechanically generated piezocharges lowers the barrier height which largely facilitates the charge transport across the CuI/ZnO heterojunction/interface and the performance of as-fabricated device were further enhanced by external strains. The photosensing behaviors of the CuI/ZnO photodetector are systematically investigated under different strain and illumination conditions. Under compressive strain, the optimum performance of flexible CuI/ZnO thin film as UV photodetector is attributed to the formation of pn heterojunction, which further modulated through the piezo-phototronic effect and improves the efficiency of charge separation as a result. Our works demonstrate merits of piezoelectric and piezo-phototronic effects for the design of energy harvesting and optoelectronic nanodevices by engineering piezoelectric/semiconductor materials interface. Graphical abstract: Highlights: Enhanced piezoelectric output by the formation of a p-CuI/n-ZnO junction from 0.8 V to 5.0 V. Piezo-phototronic effect enhanced photoresponsivity (384%) based on CuI/ZnO pn junction. The simplified fabrication process is suitable for scalable piezo-phototronic device production.