title: Nearly lattice matched all wurtzite CdSe/ZnTe type II core-shell nanowires with epitaxial interfaces for photovoltaics.
abstract: Achieving a high-quality interface is of great importance in core-shell nanowire solar cells, as it significantly inhibits interfacial recombination and thus improves the photovoltaic performance. Combining thermal evaporation of CdSe and pulsed laser deposition of ZnTe, we successfully synthesized nearly lattice matched all wurtzite CdSe/ZnTe core-shell nanowires on silicon substrates. Comprehensive morphological and structural characterizations revealed that a wurtzite ZnTe shell layer epitaxially grows over a wurtzite CdSe core nanowire with an abrupt interface. Further optical studies confirmed a high-quality interface and demonstrated efficient charge separation induced by the type-II band alignment. A representative photovoltaic device has been demonstrated and yielded an energy-conversion efficiency of 1.7% which can be further improved by surface passivation. The all-wurtzite core-shell nanowire with an epitaxial interface offers an attractive platform to explore the piezo-phototronic effect and promises an efficient hybrid nano-sized, energy harvesting system.
authors.affiliation: Advanced Materials Research Institute, University of New Orleans, New Orleans, LA 70148, USA. wzhou@uno.edu.
authors.forename: Kai
authors.initials: K
authors.lastname: Wang
authors.forename: Satish C
authors.initials: SC
authors.lastname: Rai
authors.forename: Jason
authors.initials: J
authors.lastname: Marmon
authors.forename: Jiajun
authors.initials: J
authors.lastname: Chen
authors.forename: Kun
authors.initials: K
authors.lastname: Yao
authors.forename: Sarah
authors.initials: S
authors.lastname: Wozny
authors.forename: Baobao
authors.initials: B
authors.lastname: Cao
authors.forename: Yanfa
authors.initials: Y
authors.lastname: Yan
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Weilie
authors.initials: W
authors.lastname: Zhou
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D004560:Electricity; D004566:Electrodes; D053770:Nanowires / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry*; D012825:Silicon / Q000737:chemistry; D012993:Solar Energy; D013691:Tellurium / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
chemical_list: D019187:Cadmium Compounds; D018036:Selenium Compounds; C058667:cadmium selenide; D015032:Zinc; D013691:Tellurium; D012825:Silicon