title: Lead-Free Perovskite Nanowire Array Photodetectors with Drastically Improved Stability in Nanoengineering Templates.
abstract: Organometal halide perovskite materials have triggered enormous attention for a wide range of high-performance optoelectronic devices. However, their stability and toxicity are major bottleneck challenges for practical applications. Substituting toxic heavy metal, that is, lead (Pb), with other environmentally benign elements, for example, tin (Sn), could be a potential solution to address the toxicity issue. Nevertheless, even worse stability of Sn-based perovskite material than Pb-based perovskite poses a great challenge for further device fabrication. In this work, for the first time, three-dimensional CH3NH3SnI3perovskite nanowire arrays were fabricated in nanoengineering templates, which can address nanowire integration and stability issues at the same time. Also, nanowire photodetectors have been fabricated and characterized. Intriguingly, it was discovered that as the nanowires are embedded in mechanically and chemically robust templates, the material decay process has been dramatically slowed down by up to 840 times, as compared with a planar thin film. This significant improvement on stability can be attributed to the effective blockage of diffusion of water and oxygen molecules within the templates. These results clearly demonstrate a new and alternative strategy to address the stability issue of perovskite materials, which is the major roadblock for high-performance optoelectronics.
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: Aashir
authors.identifier: 0000-0002-6929-8373
authors.initials: A
authors.lastname: Waleed
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR, China.|Department of Materials Science and Engineering, Sharif University of Technology , Azadi Avenue, 113659466 Tehran, Iran.
authors.forename: Mohammad Mahdi
authors.initials: MM
authors.lastname: Tavakoli
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: Leilei
authors.initials: L
authors.lastname: Gu
authors.affiliation: Department of Optical Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Ziyi
authors.initials: Z
authors.lastname: Wang
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: Daquan
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan ROC.
authors.forename: Arumugam
authors.initials: A
authors.lastname: Manikandan
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: Qianpeng
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Optical Science and Engineering, Fudan University , Shanghai 200433, China.
authors.forename: Rongjun
authors.initials: R
authors.lastname: Zhang
authors.affiliation: Department of Materials Science and Engineering, National Tsing Hua University , Hsinchu 30013, Taiwan ROC.
authors.forename: Yu-Lun
authors.identifier: 0000-0002-0155-9987
authors.initials: YL
authors.lastname: Chueh
authors.affiliation: Department of Electronic and Computer Engineering, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong SAR, China.
authors.forename: Zhiyong
authors.identifier: 0000-0002-5397-0129
authors.initials: Z
authors.lastname: Fan
keywords: Organometal perovskite material; nanowire; photodetector; porous alumina template; stability