Recovering near-band-edge ultraviolet responses in a wide-bandgap oxide with dipole-forbidden bandgap transition

Autor:	Qing-Cheng Liang, Rui Deng, Bin Yao, Zhipeng Wei, Zhanhui Ding, Jieming Qin, Lei Liu, Yongfeng Li, Xuan Fang
Rok vydání:	2015
Předmět:	Materials science Photoluminescence business.industry Band gap Mechanical Engineering Metals and Alloys Heterojunction medicine.disease_cause Photodiode law.invention Dipole Responsivity Absorption edge Mechanics of Materials law Materials Chemistry medicine Optoelectronics business Ultraviolet
Zdroj:	Journal of Alloys and Compounds. 649:625-629
ISSN:	0925-8388
DOI:	10.1016/j.jallcom.2015.07.186
Popis:	High-density SnO 2 nanobelts were synthesized on p-Si substrate to form a SnO 2 nanobelts/p-Si heterojunction photodiode. The photodiode shows a rectification characteristic in current–voltage measurements and exhibits an ultraviolet peak responsivity with an ultraviolet–visible rejection ratio (R395 nm/R550 nm) of two orders of magnitude. The peak responsivity is located at around 395 nm (3.14 eV), much smaller than optical absorption edge of bulk SnO 2 (∼344 nm, 3.6 eV). A strong ultraviolet peak from SnO 2 nanobelts at ∼400 nm was observed in the photoluminescence spectrum, indicating that the dipole-forbidden rule of bulk SnO 2 is broken for the nanostructural counterparts. First-principles calculations suggest that surface state in nanostructure plays a key role in breaking dipole forbidden rule and realizing ultraviolet peak responsivity.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::d8ce53a8a2a69a9d39121006a24d6c6d https://doi.org/10.1016/j.jallcom.2015.07.186 Zobrazit plný text záznamu Full Text from ScienceDirect