Premium
Deeply Repairing Surface States with Wet Chemistry Methods: Enhanced Performance in TiO 2 Nanowire Arrays‐Based Optoelectronic Device
Author(s) -
Zha Chenyang,
Zhang JunJie,
Shen Liming,
Dong Shuai,
Gupta Arunava,
Bao Ningzhong
Publication year - 2017
Publication title -
chemistryselect
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.437
H-Index - 34
ISSN - 2365-6549
DOI - 10.1002/slct.201701837
Subject(s) - nanowire , materials science , nanotechnology , photoluminescence , quantum dot , solar cell , rutile , nanocrystal , adsorption , surface states , optoelectronics , annealing (glass) , ionic bonding , nanoparticle , chemical engineering , chemistry , ion , surface (topology) , geometry , mathematics , organic chemistry , engineering , composite material
One‐dimensional (1D) single‐crystalline rutile TiO 2 nanowire arrays (TiO 2 NWAs) have generally been considered superior over TiO 2 nanoparticle films for the optoelectronic applications. We discovered that the conventional oxygen annealing method cannot efficiently repair the surface trap states of the TiO 2 NWAs that significantly influence the charge diffusion. In this work, we demonstrate a highly effective wet chemistry method to repair the surface states by the successive ionic layer adsorption and reaction (SILAR). The density functional calculations (DFT)‐based simulation has been used to explain the physical mechanism of reparation of the surface oxygen vacancies of by CdS or PbS quantum dots (QDs). The analysis results of photoluminescence spectroscopy (PL) and electrochemical analysis conformed the enhanced optoelectronic conversion efficiency. A 20–30% improvement in solar cell performance has been obtained over the PbS or CdS QDs coated dye‐sensitized solar cells. The SILAR method for deeply repairing the surface trap states can be extended to the systhesis of other semiconducting nanocrystals and its solar energy conversion applications.