Journal of the Korean Applied Science and Technology (한국응용과학기술학회지)

The Korean Society of Applied Science and Technology (한국응용과학기술학회)
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The Influence of Current Flow on OH Radical Generation in a Photocatalytic Reactor of TiO2 Nanotube Plates

전류흐름에 따른 TiO2 nanotube 광촉매의 OH radical 생성량 평가

  • Kim, Da-Eun (Graduate School of Energy and Environment, Seoul National University of Technology & Science) ;
  • Lee, Yong-Ho (Graduate School of Energy and Environment, Seoul National University of Technology & Science) ;
  • Kim, Dae-Won (Techross Inc.) ;
  • Pak, Dae-Won (Graduate School of Energy and Environment, Seoul National University of Technology & Science)
  • 김다은 (서울과학기술대학교 에너지환경대학원 에너지환경공학과) ;
  • 이용호 (서울과학기술대학교 에너지환경대학원 에너지환경공학과) ;
  • 김대원 ((주)테크로스) ;
  • 박대원 (서울과학기술대학교 에너지환경대학원 에너지환경공학과)
  • Received : 2017.05.30
  • Accepted : 2017.06.25
  • Published : 2017.06.30
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Abstract

OH radical generation is one of the common method to evaluate photocatalytic activity. In many of previous studies, only the UV(Ultraviolet) light was applied to test photocatalytic ability of $TiO_2$ nanotubes by studying probe compound(4-Chlorobenzoic acid) concentration change in solution. Also, $TiO_2$ nanotubes were found to show some electrochemical characteristics when the flow of electric current was applied. In this study, the flow of electric current and UV light were applied at the same time to determine whether electrochemical characteristics of $TiO_2$ nanotube plate can give synergetic effect on the photocatalytic activity. $TiO_2$ nanotube was grown on Ti by anodic oxidation to create $TiO_2$ nanotube plate which can be used as a photocatalyst and a electrode that can undergo AOP(Advanced Oxidation Process) for water treatment. Probe compound solution was prepared using 4-chlorobenzoic acid and $H_2O$ as a solvent. NaCl was added to give conductivity to work as electrolyte. As a result, enough level of electric current flow was found to give synergetic photocatalytic effect which can be used for efficient AOP water treatment method.

본 연구에서는 $TiO_2$ nanotube 광촉매의 고도산화처리능을 비교하기 위해서 OH 라디칼 생성력을 평가하고자 하였다. 자외선 조사에 따른 Probe compound인 4-Chlorobenzoic acid (pCBA)의 농도 감소에 따라 OH radical 생성량을 산정하는 방법으로 광촉매 효율을 평가하였는데, $TiO_2$ nanotube 표면에서의 전자의 흐름을 원활하게 하기 위하여 전기적 에너지를 주었을 시 광촉매 효율의 증가 가능성 또한 확인하고자 자외선 조사 시 전류밀도를 인가하는 방법으로 실험을 진행하였다. 실험에 사용된 $TiO_2$ nanotube는 전극효과를 부여하기 위해 양극산화법으로 티타늄판을 이용하여 제조하였으며, pCBA 용액에는 전도도를 부여하기 위하여 NaCl을 첨가하여 전해질로 사용하였다. 정전류 정전압 조건하에서 자외선조사 실험을 진행하였으며, 전류가 흐르는 광촉매에 자외선 조사 시 OH 라디칼 생성량은 광촉매 없이 자외선만 조사하였을 때에 비해 약 5.6배, $TiO_2$ 광촉매와 함께 자외선을 조사하였을 보다 약 2.2배 증가하였다. 결과적으로 광촉매반응에 전기적 에너지를 부여하였을 시 시너지효과를 가져올 수 있는 가능성을 확인할 수 있었다.

Keywords

References

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