title: Inverted nanocone-based thin film photovoltaics with omnidirectionally enhanced performance.
abstract: Thin film photovoltaic (PV) technologies are highly attractive for low-cost solar energy conversion and possess a wide range of potential applications from building-integrated PV generation to portable power sources. Inverted nanocones (i-cones) have been demonstrated as a promising structure for practical thin film PV devices/modules, owning to their antireflection effect, self-cleaning function, superior mechanical robustness, and so forth. In this work, we have demonstrated a low-cost and scalable approach to achieve perfectly ordered i-cone arrays. Thereafter, thin film amorphous silicon (a-Si:H) solar cells have been fabricated based on various i-cone substrates with different aspect ratios and pitches to investigate the impact of geometry of i-cone nanostructures on the performance of the as-obtained PV devices. Intriguingly, the optical property investigations and device performance characterizations demonstrated that the 0.5-aspect-ratio i-cone-based device performed the best on both light absorption capability and energy conversion efficiency, which is 34% higher than that of the flat counterpart. Moreover, the i-cone-based device enhanced the light absorption and device performance over the flat reference device omnidirectionally. These results demonstrate a viable and convenient route toward scalable fabrication of nanostructures for high-performance thin film PV devices based on a broad range of materials.
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong, China.
authors.forename: Qingfeng
authors.initials: Q
authors.lastname: Lin
authors.forename: Siu-Fung
authors.initials: SF
authors.lastname: Leung
authors.forename: Linfeng
authors.initials: L
authors.lastname: Lu
authors.forename: Xiaoyuan
authors.initials: X
authors.lastname: Chen
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chen
authors.forename: Haoning
authors.initials: H
authors.lastname: Tang
authors.forename: Wenjun
authors.initials: W
authors.lastname: Su
authors.forename: Dongdong
authors.initials: D
authors.lastname: Li
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Fan