Photoelectrochemical study of Ta3N5 nanotubes for water splitting

Brazil MRS Meeting 2014

Khan, Sherdil^1 ; Santos, Marcos J. Leite^2 ; Dupont, Jairton^2 ; Teixeira, Sergio R.^1

Instituto de Física, Universidade Federal Do Rio Grande Do sul, Av Bento Gonçalves 9500 POBox 15051, CEP 91501-970, POA-RS, Brazil^1

Instituto de Química, Universidade Federal Do Rio Grande Do sul, Av Bento Gonçalves 9500 POBox 15003, CEP 91501-970, POA-RS, Brazil^2

关键词: Linear sweep voltammetry;    Photocatalytic performance;    Photoelectrochemicals;    Photogenerated holes;    Recombination centers;    UV-vis spectrophotometry;    Water oxidation;    Water splitting;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/97/1/012007/pdf
DOI  :  10.1088/1757-899X/97/1/012007

来源: IOP

【 摘 要 】

Nanotubes (NTs) of Ta3N5were synthesized by nitridation of Ta2O5NTs. The samples were studied by scanning electron microscopy, UV-VIS spectrophotometry, x-ray diffraction and photoelectrochemical (PEC) measurements carried out in aqueous solutions of Na2SO4and Fe(CN)63-/4-. The results show the presence of trapping states on illuminated pristine Ta3N5NTs in Na2SO4(aq). These trapping states act as recombination center for photogenerated holes, affecting the photocatalytic performance of Ta3N5NTs. On the other hand, by using Fe(CN)63-/4-(aq) the photogenerated holes were scavenged efficiently without giving rise to the trapping states at Ta3N5NTs/solution interface. The results obtained by cyclic voltammetry, linear sweep voltammetry and electrochemical impedance spectroscopy have shown that the presence of these trapping states is a limiting step for water oxidation using pristine Ta3N5NTs.