tailieunhanh - Báo cáo hóa học: " The correlation between radiative surface defect states and high color rendering index from ZnO nanotubes"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: The correlation between radiative surface defect states and high color rendering index from ZnO nanotubes | Sadaf et al. Nanoscale Research Letters 2011 6 513 http content 6 1 513 o Nanoscale Research Letters a SpringerOpen Journal NANO EXPRESS Open Access The correlation between radiative surface defect states and high color rendering index from ZnO nanotubes 1 1 1 1 w P s 2 2 Jamil R Sadaf Muhammad Q Israr Omer Nur Magnus Willander Yong Ding and Zhong L Wang Abstract Combined surface structural and opto-electrical investigations are drawn from the chemically fashioned ZnO nanotubes and its heterostructure with p-GaN film. A strong correlation has been found between the formation of radiative surface defect states in the nanotubes and the pure cool white light possessing averaged eight color rendering index value of 96 with appropriate color temperature. Highly important deep-red color index value has been realized 95 which has the capability to render and reproduce natural and vivid colors accurately. Diverse types of deep defect states and their relative contribution to the corresponding wavelengths in the broad emission band is suggested. Keywords ZnO nanotubes ZnO GaN heterostructure radiative surface defects color rendering index R9 color indexed Introduction The solid-state lighting holds tremendous prospective for future illumination backlight panel display industry and biomedical applications due to their brightness and durability 1-3 . Over the past decade much attention has been drawn towards white-light-emitting diodes WLEDs as new light sources due to their reliability with great economic and ecological consequences. So far different materials and a number of nanostructures are being used to fabricate WLEDs such as phosphors nanocrystals polymers and nanocrystal-polymer combination 4-7 . To this end phosphor and polymers are being studied comprehensively for wavelength conversion and to generate full-color emission but still much efforts are required to achieve the light-emitting devices with high color rendering index CRI value .