Sains Malaysiana 49(12)(2020): 3209-3217

http://dx.doi.org/10.17576/jsm-2020-4912-32

 

Electrodeposited WO3/Au Photoanodes for Photoelectrochemical Reactions

(Pengelektroendapan Fotoanod WO3/Au untuk Tindak Balas Fotoelektrokimia)

 

LORNA JEFFERY MINGGU*, NURUL AKMAL JAAFAR, KIM HANG NG, KHUZAIMAH ARIFIN & ROZAN MOHAMAD YUNUS

 

Fuel Cell Institute, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

Diserahkan: 17 Ogos 2020/Diterima: 11 September 2020

 

ABSTRACT

This work aims to study the effect of gold (Au) loading on the photoelectrochemical behavior of tungsten trioxide (WO3) photoelectrodes. The WO3 film has been fabricated via electrodeposition method with constant potential on fluorine doped tin oxide (FTO) glass substrate. The Au nanoparticle loading on WO3 films surface was also prepared by constant potential electrodeposition. Due to the small amount of Au loading, the band gap values of the plasmonized WO3 remained around 2.6 eV. However, during the photoelectrochemical analysis, the photoactivity of the plasmonized WO3 photoelectrodes improved >100% with a minimal amount of Au loading compared to the pristine WO3. The photocurrent generation was further enhanced with the presence of organic donors (methanol and formic acid). The photocurrent achieved 3.74 mA/cm2 when 1.0 M of formic acid was added. Plausible charge transfer mechanism was suggested.

 

Keywords: Au nanoparticles; electrodeposition; photoelectrochemical; waste degradation; WO3 films

 

ABSTRAK

Kajian ini bertujuan untuk menguji kesan muatan aurum (Au) terhadap perilaku fotoelektrokimia fotoelektrod tungsten trioksida (WO3). Filem WO3 telah dihasilkan melalui kaedah elektroendapan potensi malar ke atas kaca bersalut timah oksida terdop florin (FTO). Nanopartikel Au dimendapkan ke atas permukaan filem WO3 dengan kaedah elektroendapan potensi malar. Jurang tenaga WO3 berplasmon kekal sekitar 2.6 eV disebabkan muatan Au yang sangat kecil. Namun begitu, semasa analisis fotoelektrokimia, fotoaktiviti fotoelektrod WO3 berplasmon telah meningkat >100% dengan muatan Au yang minimum berbanding WO3 tulen. Penjanaan fotoarus telah ditingkatkan lagi dengan penambahan penderma