TY - JOUR

T1 - One-step hydrothermal synthesis of Bi-TiO2 nanotube/graphene composites

T2 - An efficient photocatalyst for spectacular degradation of organic pollutants under visible light irradiation

AU - Alam, U.

AU - Fleisch, M.

AU - Kretschmer, I.

AU - Bahnemann, D.

AU - Muneer, M.

N1 - Funding information: This work was financially supported by research project from Ministry of Mines, government of India, New Delhi and Alexander von Humboldt Foundation , Germany under research group linkage program. The authors would also like to acknowledge DST and UGC, for research support (DRS II, PURSE & FIST) to the Department of Chemistry, AMU, Aligarh. We are thankful to Dr. Faryal Idrees for her valuable suggestions in drafting the manuscript.

PY - 2017/12/5

Y1 - 2017/12/5

N2 - In the present study, we have adopted a simple one-pot alkaline hydrothermal route to synthesize Bi-doped TiO 2NT/graphene composites by using different wt% of Bi with an aim to achieve the excellent photocatalytic activity under visible light source. The nature of GO is changed to deoxygenated graphene with simultaneous embedding of Bi into TiO 2 nanotube (TNT), during hydrothermal process. XRD and FTIR analysis confirm the successful conversion of GO to deoxygenated graphene. EPR analysis reveals the co-existence of Ti 3+ ion with oxygen vacancy, which is created by the Bi doping. The photocatalytic activity of the prepared samples is measured by the degradation of aqueous suspensions of methylene blue (MB) and Dinoseb (phenolic herbicide), under visible-light irradiation. The prepared TiO 2NT/graphene composite with 2-wt% bismuth (2-BTNTG) has shown the improved photocatalytic activity as compared to their counterparts. The improved photocatalytic activity is associated to the synergistic effect of graphene and Bi-TNT, which facilitate the interfacial charge transfer and enhances the efficiency of light harvesting in the visible region. Moreover, the underlying mechanism involving photocatalytic degradation of organic pollutants over 2-BTNTG is explored by using trapping experiments, suggesting that the .OH radicals solely contributed to degradation.

AB - In the present study, we have adopted a simple one-pot alkaline hydrothermal route to synthesize Bi-doped TiO 2NT/graphene composites by using different wt% of Bi with an aim to achieve the excellent photocatalytic activity under visible light source. The nature of GO is changed to deoxygenated graphene with simultaneous embedding of Bi into TiO 2 nanotube (TNT), during hydrothermal process. XRD and FTIR analysis confirm the successful conversion of GO to deoxygenated graphene. EPR analysis reveals the co-existence of Ti 3+ ion with oxygen vacancy, which is created by the Bi doping. The photocatalytic activity of the prepared samples is measured by the degradation of aqueous suspensions of methylene blue (MB) and Dinoseb (phenolic herbicide), under visible-light irradiation. The prepared TiO 2NT/graphene composite with 2-wt% bismuth (2-BTNTG) has shown the improved photocatalytic activity as compared to their counterparts. The improved photocatalytic activity is associated to the synergistic effect of graphene and Bi-TNT, which facilitate the interfacial charge transfer and enhances the efficiency of light harvesting in the visible region. Moreover, the underlying mechanism involving photocatalytic degradation of organic pollutants over 2-BTNTG is explored by using trapping experiments, suggesting that the .OH radicals solely contributed to degradation.

KW - Bi-TiO NT/graphene

KW - Dinoseb

KW - Methylene blue

KW - Photocatalytic activity

UR - http://www.scopus.com/inward/record.url?scp=85027870911&partnerID=8YFLogxK

U2 - 10.1016/j.apcatb.2017.06.016

DO - 10.1016/j.apcatb.2017.06.016

M3 - Article

VL - 218

SP - 758

EP - 769

JO - Applied Catalysis B: Environmental

JF - Applied Catalysis B: Environmental

SN - 0926-3373

ER -