title: Amorphous Semiconductor Nanowires Created by Site-Specific Heteroatom Substitution with Significantly Enhanced Photoelectrochemical Performance.
abstract: Semiconductor nanowires that have been extensively studied are typically in a crystalline phase. Much less studied are amorphous semiconductor nanowires due to the difficulty for their synthesis, despite a set of characteristics desirable for photoelectric devices, such as higher surface area, higher surface activity, and higher light harvesting. In this work of combined experiment and computation, taking Zn2GeO4 (ZGO) as an example, we propose a site-specific heteroatom substitution strategy through a solution-phase ions-alternative-deposition route to prepare amorphous/crystalline Si-incorporated ZGO nanowires with tunable band structures. The substitution of Si atoms for the Zn or Ge atoms distorts the bonding network to a different extent, leading to the formation of amorphous Zn1.7Si0.3GeO4 (ZSGO) or crystalline Zn2(GeO4)0.88(SiO4)0.12 (ZGSO) nanowires, respectively, with different bandgaps. The amorphous ZSGO nanowire arrays exhibit significantly enhanced performance in photoelectrochemical water splitting, such as higher and more stable photocurrent, and faster photoresponse and recovery, relative to crystalline ZGSO and ZGO nanowires in this work, as well as ZGO photocatalysts reported previously. The remarkable performance highlights the advantages of the ZSGO amorphous nanowires for photoelectric devices, such as higher light harvesting capability, faster charge separation, lower charge recombination, and higher surface catalytic activity.
authors: School of Materials Science and Engineering, Tongji University , Shanghai 201804, P. R. China.|Research Center for Translational Medicine & Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine , No. 150 Jimo Road, Shanghai 200120, P. R. China.
authors: Ting
authors: T
authors: He
authors: School of Chemical Science and Engineering, Tongji University , Shanghai 200092, P. R. China.
authors: Lianhai
authors: L
authors: Zu
authors: School of Chemical Science and Engineering, Tongji University , Shanghai 200092, P. R. China.
authors: Yan
authors: Y
authors: Zhang
authors: Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Environmental Chemistry, College of Chemistry, Central China Normal University , Wuhan 430079, P. R. China.
authors: Chengliang
authors: C
authors: Mao
authors: School of Chemical Science and Engineering, Tongji University , Shanghai 200092, P. R. China.
authors: Xiaoxiang
authors: X
authors: Xu
authors: School of Chemical Science and Engineering, Tongji University , Shanghai 200092, P. R. China.|Research Center for Translational Medicine & Key Laboratory of Arrhythmias of the Ministry of Education of China, East Hospital, Tongji University School of Medicine , No. 150 Jimo Road, Shanghai 200120, P. R. China.
authors: Jinhu
authors: J
authors: Yang
authors: Department of Chemistry, The Hong Kong University of Science and Technology , Clear Water Bay, Kowloon, Hong Kong P. R. China.
authors: Shihe
authors: S
authors: Yang
keywords: amorphous nanowires; bonding distortion; photoelectrochemical water splitting; semiconductor; site-specific heteroatom substitution