best365手机官方网站|首页_欢迎您

(9月26日)New Mixed Anion Photocatalysts for Visible Light Induced Water Splitting
best365手机客户端类型:学术活动  阅读次数:  发布时间:2019-09-25

报告题目:New Mixed Anion Photocatalysts for Visible Light Induced Water Splitting

报告人:Prof. Ryu ABE (教授、日本京都大学,)

报告时间:2019年9月26日(星期四)下午15:00-17:00

报告地点:福州大学阳光科技大厦北911室

报告摘要:

Photo-induced water  splitting  using  semiconductor photocatalysts  has  attracted  considerable  attention for  producing  H2  as  a  clean  energy  carrier,  while the effective utilization of visible light is imperative to  achieve  the  desired  efficiency  for  practical applications.[1] Various  mixed-anion  compounds such  as  oxynitrides,  oxysulfides,  and  oxyhalides have  been  extensively  studied  as  promising photocatalysts  for  visible  light-induced  water splitting,  because  their  valence  band  maximum (VBM)  values  are  generally  more  negative  than those of conventional oxides, due  to  the significant contribution  of  high-energy  p  orbitals  of  the  non-oxide  anions  (e.g.,  N-2p,  S-3p,  Br-4p,  and  I-5p) mixed  with  O-2p.  Some  tantalum  oxynitrides (TaON  and  BaTaO2N)  have  been  successfully employed  as  a  H2-evolving  photocatalyst  in  Z-scheme  water  splitting  systems,  combined  with another O2-evolving  photocatalyst  such  as WO3.[2] However,  most  of mixed-anion  compounds  suffer from facile self-oxidative deactivation of non-oxide

anions  by  photogenerated  holes,  thereby  imposing surface  modifications  such  as  loading  some cocatalysts to circumvent the oxidative deactivation. For  example,  we  have  demonstrated  that  the loading  of  IrO2  or  CoOx  nanoparticles  as  a cocatalyst  for water  oxidation  on  such  oxynitrides suppress  the  self-oxidative  deactivation  to  some extent,  and  thus  enable  us  to  employ  such  surface modified  (oxy)nitrides  (TaON  and  Ta3N5)  as  O2-evolving  photocatalysts  in  Z-scheme  systems with (IO3/I)  redox.[2] Such  surface  modification  has been  proven  effective  for  the  fabrication  of  (oxy)nitride-based  photoanode.  The  porous tantalum oxynitrides (TaON or BaTaO2N) electrode prepared  on  conducting  substrates  showed relatively  stable  O2  evolution  with  significantly high  quantum  efficiency  in  an  aqueous  solution, after  loading  of  effective  cocatalyst  nanoparticles for water oxidation.[3,4]   

 We  have  recently  demonstrated  that  Sillén–Aurivillius  type  perovskite  oxyhalides  such  as Bi4NbO8Cl can stably and efficiently oxidize water to  O2  under  visible  light  without  any  surface modifications,  and  also  exhibits  a  stable Z-scheme water  splitting when  coupled  with  a  H2-evolving photocatalyst.[5] It was  revealed  that  the VBMs  of these  materials  consist  mainly  of  O-2p  orbitals, instead of Cl-3p  (or Br-4p), but  their positions  are much  more  negative  than  those  of  conventional oxides.  Thus,  they  possess  narrow  bandgaps  for visible  light  absorption  as  well  as  sufficiently negative  CBMs  for  water  reduction.  DFT calculation  visualized  a  fairly  strong  hybridization between  the  Bi-6s  and  O-2p  orbitals,  which  can explain  why  the  O-2p  orbitals  are  elevated  in energy, combined with  the  result on Madelung  site potential  analysis  that  can  rationalize  the  origin  of  high  energy  of O-2p  orbital  in  these materials.[6, 7] Since O–anions  are  known  to  be  relatively  stable, photogenerated holes populated at the O-2p orbitals will  not  lead  to  self-decomposition  but  to  oxidize water.  These  results  could  provide  new  strategies for developing durable materials for water splitting under visible  light, by manipulating  the  interaction between  post-transition  metal  s  orbitals  and  O-2p orbitals.  We  also  extended  this  strategy  to  other oxyhalides  such  as  double-layered  perovskite AA’Bi3M2O11Cl  (A, A’: Sr, Ba, Pb, Bi; M: Ta, Nb, Ti) [8] and Sillén type PbBiO2X (X: Cl, Br)[9].

References

1.  R. Abe, J. Photochem. Photobiol. C: Photochem. Rev. 2011, 11, 179.

2.  R.  Abe,  J.  Tang  et  al.  Chem.  Rev.  2018, 118, 5201.

3.  M.  Higashi,  K.  Domen,  R.  Abe,  J. Am. Chem. Soc. 2012, 134, 6968.

4.  M.  Higashi,  K.  Domen,  R.  Abe,  J.  Am. Chem. Soc. 2013, 135, 10238.

5.  H. Fujito, H. Kunioku, H. Kageyama, R. Abe et al., J. Am. Chem. Soc. 2016, 38, 2082.

6.  D. Kato, H. Kunioku, R. Abe, H. Kageyama et al. J. Am. Chem. Soc. 2017, 139, 18725.

7.  H.  Kunioku,  H.  Kageyama,  R.  Abe  et  al.,  J. Mater. Chem. A 2018, 6, 3100.

8.  A. Nakada, H. Kageyama, R. Abe et  al., Chem. Mater. 2019, 31, 3419.

9.  H. Suzuki, H. Kageyama, R. Abe  et  al., Chem. Mater. 2018, 30, 5862.

个人介绍:

Education:

1996  B. Sc., Tokyo Institute of Technology, Tokyo, Japan

1998  Ms. Sc., Tokyo Institute of Technology, Tokyo, Japan

2001  PhD., Tokyo Institute of Technology, Tokyo, Japan   

Professional career:

2001~  Postdoc, National Institute of Advanced Industrial Science and Technology

(AIST), Tsukuba, Japan

2002~  Researcher, National Institute of Advanced Industrial Science and Technolo

(AIST), Tsukuba, Japan

2005~  Associate Professor, Hokkaido University, Sapporo, Japan

2012~  Professor, Kyoto University, Kyoto, Japan

Awards/other information:

2003  Encouraging Prize of The Japan Institute of Energy

2003  Best Presentation Award in The International Conference of Solar Light En

2008  The Chemical Society of Japan Award for Young Chemists

2019  The Japanese Photochemistry Association Award

Activities:

2014~  Associate Editor, Chemistry Letters

2014~  Associate Editor, J. Photochem. Photobiol. C. Photochem. Rev.

2016~  Associate Editor, J. Photochem. Photobiol. A. Chemistry

2016~  Associate Editor, Sustainable Energy and Fuels

2016~  Director, The Japanese Photochemistry Association

Publications (published:145, cited numbers: 11044, h-index: 53)

Copyright © 2010-2018 best365官网版权所有 书记信箱 院长信箱
地址: 福建省福州市福州大学城乌龙江北大道2号 邮编:350108 电邮: hxxy@fzu.edu.cn 电话: 0591-22866234
Design&Operations By Zeze