TY - JOUR
T1 - Cost-effective large-scale synthesis of oxygen-defective ZnO photocatalyst with superior activities under UV and visible light
AU - Wang, Jing
AU - Chen, Ruosong
AU - Xia, Yi
AU - Wang, Guifang
AU - Zhao, Hongyuan
AU - Xiang, Lan
AU - Komarneni, Sridhar
N1 - Funding Information:
This work was financially supported by the National Science Foundation of China (Nos. 51174125, 51234003 and 51374138), National Key Technology Research and Development Program of China (2013BAC14B02). Jing Wang is grateful for the scholarship from China Scholarship Council (No. 201506210232).
Publisher Copyright:
© 2016 Elsevier Ltd and Techna Group S.r.l.
PY - 2017/2/1
Y1 - 2017/2/1
N2 - A cost-effective solution method was developed to produce ZnO photocatalyst in large quantity, through the conversion of ε-Zn(OH)2 to ZnO in NaOH solutions. Experimental results indicated that the concentrated NaOH solution (4 mol L−1) promoted the rapid formation of ZnO owing to the enhanced dissolution-precipitation reactions. The large-scale synthesis was also achieved with high-yield and solvent-recyclability. Structural analysis based on X-ray photoelectron spectroscopy, electron spin resonance and photoluminescence revealed that the as-prepared ZnO photocatalyst was rich in oxygen vacancies (VO). The VO-rich ZnO photocatalyst exhibited improved visible-light absorption, higher photocurrent responses and superior activities toward the degradation of rhodamine B under both UV (λ~254 nm) and visible-light illumination (λ>420 nm) compared to commercial ZnO and P25 TiO2 powders, as well as good cycle stability. Based on the results of photoluminescence and active species detection, the VO-enhanced photocatalytic activity was attributed to the generation of VO-isolated level in the band structure. Under UV light, the VO-level could promote charge separation by trapping the photoinduced electrons, while under visible-light, the VO-level improved visible-light absorption and facilitated the charge generation. The presently developed synthesis may potentially benefit the large-scale production and low-cost application of ZnO photocatalyst for solar energy utilization.
AB - A cost-effective solution method was developed to produce ZnO photocatalyst in large quantity, through the conversion of ε-Zn(OH)2 to ZnO in NaOH solutions. Experimental results indicated that the concentrated NaOH solution (4 mol L−1) promoted the rapid formation of ZnO owing to the enhanced dissolution-precipitation reactions. The large-scale synthesis was also achieved with high-yield and solvent-recyclability. Structural analysis based on X-ray photoelectron spectroscopy, electron spin resonance and photoluminescence revealed that the as-prepared ZnO photocatalyst was rich in oxygen vacancies (VO). The VO-rich ZnO photocatalyst exhibited improved visible-light absorption, higher photocurrent responses and superior activities toward the degradation of rhodamine B under both UV (λ~254 nm) and visible-light illumination (λ>420 nm) compared to commercial ZnO and P25 TiO2 powders, as well as good cycle stability. Based on the results of photoluminescence and active species detection, the VO-enhanced photocatalytic activity was attributed to the generation of VO-isolated level in the band structure. Under UV light, the VO-level could promote charge separation by trapping the photoinduced electrons, while under visible-light, the VO-level improved visible-light absorption and facilitated the charge generation. The presently developed synthesis may potentially benefit the large-scale production and low-cost application of ZnO photocatalyst for solar energy utilization.
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U2 - 10.1016/j.ceramint.2016.10.146
DO - 10.1016/j.ceramint.2016.10.146
M3 - Article
AN - SCOPUS:85005949793
VL - 43
SP - 1870
EP - 1879
JO - Ceramics International
JF - Ceramics International
SN - 0272-8842
IS - 2
ER -