Boron Environments in B-Doped and (B, N)-Codoped TiO2 Photocatalysts: A Combined Solid-State NMR and Theoretical Calculation Study
The structures and local environments of boron species in B-doped and (B, N)-codoped TiO2 photocatalysts have been investigated by solid-state 11B NMR spectroscopy in conjunction with density functional theory (DFT) calculations.Up to seven different boron sites were identified in the B-doped anatase TiO2, which may be classified into three categories,including interstitial, bulk BOa/:2 polymer, and surface boron species, and has been supported by results obtained from FT-1R and XPS spectroscopy as well as from DFT calculations.Two types of interstitial borons, namely the tricoordinated (T*)-and pseudotetrahedral-coordinated (Q*) borons, were observed in addition to the two types of bulk BO3/2 polymer and three types of surface B, in good agreement with experimental data.Further density of state analyses revealed that, compared to undoped TiO2, the T* species in boron-doped TiO2 are solely responsible for the observed increase in energy band gap, whereas the presence of Q* species tend to lead to a decrease in band gap and hence are more favorable for the absorption in the visible-light region.In comparison with B-and N-doped TiO2, (B, N)-codoped TiO2 tends to exhibit a much higher visible-light photocatalytic activity for the oxidation of rhodamine B.Accordingly, a photochemical mechanism of the (B, N)-codoped TiO2 under visible-light irradiation is proposed.
Ningdong Feng Anmin Zheng Qiang Wang Pingping Ren Xiuzhi Gao Shang-Bin Liu Zhurui Shen Tiehong Chen Feng Deng
State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Center for Magneti Institute of Atomic and Molecular Sciences,Academia Sinica,P.O.Box 23-166,Taipei 10617,Taiwan Key Laboratory of Functional Polymer Materials of MOE,Department of Materials Chemistry,College of C
国内会议
苏州
英文
400-410
2014-10-26（万方平台首次上网日期，不代表论文的发表时间）