tailieunhanh - Báo cáo hóa học: " A simple route to vertical array of quasi-1D ZnO nanofilms on FTO surfaces: 1D-crystal growth of nanoseeds under ammonia-assisted hydrolysis process"

Tuyển tập các báo cáo nghiên cứu về hóa học được đăng trên tạp chí hóa hoc quốc tế đề tài : A simple route to vertical array of quasi-1D ZnO nanofilms on FTO surfaces: 1D-crystal growth of nanoseeds under ammonia-assisted hydrolysis process | Ali Umar et al. Nanoscale Research Letters 2011 6 564 http content 6 1 564 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access A simple route to vertical array of quasi-1D ZnO nanofilms on FTO surfaces 1D-crystal growth of nanoseeds under ammonia-assisted hydrolysis process Akrajas Ali Umar1 Mohd Yusri Abd Rahman2 Rika Taslim2 Muhamad Mat Salleh1 and Munetaka Oyama3 Abstract A simple method for the synthesis of ZnO nanofilms composed of vertical array of quasi-1D ZnO nanostructures quasi-NRs on the surface was demonstrated via a 1D crystal growth of the attached nanoseeds under a rapid hydrolysis process of zinc salts in the presence of ammonia at room temperature. In a typical procedure by simply controlling the concentration of zinc acetate and ammonia in the reaction a high density of vertically oriented nanorod-like morphology could be successfully obtained in a relatively short growth period approximately 4 to 5 min and at a room-temperature process. The average diameter and the length of the nanostructures are approximately 30 and 110 nm respectively. The as-prepared quasi-NRs products were pure ZnO phase in nature without the presence of any zinc complexes as confirmed by the XRD characterisation. Room-temperature optical absorption spectroscopy exhibits the presence of two separate excitonic characters inferring that the as-prepared ZnO quasi-NRs are high-crystallinity properties in nature. The mechanism of growth for the ZnO quasi-NRs will be proposed. Due to their simplicity the method should become a potential alternative for a rapid and cost-effective preparation of high-quality ZnO quasi-NRs nanofilms for use in photovoltaic or photocatalytics applications. PACS . Keywords ZnO quasi-NRs nanofilms vertical array hydrolysis process seed-mediated method Introduction ZnO nanocrystals such as nanorods nanowires and nanoparticles have been receiving a growing research attention in .