TiO2 DOPED WITH Fe2O3 FOR PHOTOELECTROCHEMICAL WATER SPLITTING ELECTRODE: EXPERIMENTAL AND DENSITY FUNCTIONAL THEORY STUDY

Abstract

Various modifications of the titanium dioxide thin films have been done in fulfilling the photoelectrode requirements for photoelectrochemical water splitting reaction. In this study, surface passivation of TiO 2 by hematite-Fe 2 O 3 was reported. Electrodeposition technique was used to deposit the Fe 2 O 3 onto the TiO 2 /FTO film with variation of time. X-ray diffraction (XRD), Scanning Electron Microscope (SEM) and UV-Vis spectroscopic analyses were used to characterize the electrode. Plane-wave-based pseudopotential density functional theory (DFT) calculations were used to analyze the electronic structure and charge potential at the surface of the electrode. The photocurrent measurement showed that current density of TiO 2 /Fe 2 O 3 electrode was higher than the TiO 2 /FTO under the same illumination intensity of 100 mWcm -2 . The highest current density was produced by 5 minutes electrodeposition of Fe 2 O 3 , which also shifted the absorption to visible region at the threshold wavelength of 518 nm.Keywords : titanium dioxide, iron(III) oxide, passivation layer, band gap Abstrak Pelbagai pengubahsuaian titanium dioksida filem nipis telah dilakukan untuk memenuhi keperluan fotoelektrod bagi tindak balas fotoelektrokimia pembelahan molekul air. Dalam kajian ini, dilaporkan pempasifan permukaan TiO 2 dengan bijih besi-Fe 2 O 3 . Teknik pengelektroenapan digunakan untuk mendepositkan Fe 2 O 3 ke TiO 2 /FTO filem dengan pelbagai masa pengelektroenapan. Analisis XRD, SEM dan UV-Vis spektroskopi telah digunakan untuk mencirikan elektrod. pengiraan teori fungsi ketumpatan (DFT) berasaskan planar gelombang pseudopotential telah digunakan untuk menganalisis struktur elektronik dan potensi caj di permukaan elektrod. Pengukuran arusfoto menunjukkan bahawa ketumpatan arus TiO 2 /Fe 2 O 3 elektrod adalah lebih tinggi daripada TiO 2 /FTO bawah keamatan pencahayaan yang sama, 100 mWcm -2 . Ketumpatan semasa tertinggi dihasilkan oleh 5 minit pengelektroenapan Fe 2 O 3 , yang mana penyerapan beralih ke kawasan yang boleh dilihat pada panjang gelombang ambang 518 nm.Kata kunci: titanium dioksida, ferum (III) oksida, lapisan pasif, sela jalur

Sensitive Detection of Aqueous Methanol by Electrochemical Route Using Mesoporous α-Fe2O3 Doped CdSe Nanostructures Modified Glassy Carbon Electrode

“…As a dopant α-Fe 2 O 3 enhances the properties and performance of many electronic and optoelectronic devices. [14][15][16] Doping mesoporous α-Fe 2 O 3 into CdSe is expected to be a promising choice probably because of similar d-spacing, which would facilitate the coupling between both compounds. CdSe is an n-type low band-gap semiconductor material, with a wide range of applications such as in solar cells, 17 biosensors, 18 biomedical imaging, 19 photovoltaic application, 20 electrochemical sensors, 21 and many more.…”