Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays
Co-doped and Ni-doped hematite (α-Fe<sub>2</sub>O<sub>3</sub>) nanorod arrays were prepared on fluorine-doped tin oxide (FTO) conductive glass via aqueous chemical growth, in which the doping and the formation of nanorods occurred simultaneously (i.e., in situ doping). These...
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MDPI AG
2020-05-01
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| author | Feng Cheng Xiuwei Li |
| author_facet | Feng Cheng Xiuwei Li |
| author_sort | Feng Cheng |
| collection | DOAJ |
| description | Co-doped and Ni-doped hematite (α-Fe<sub>2</sub>O<sub>3</sub>) nanorod arrays were prepared on fluorine-doped tin oxide (FTO) conductive glass via aqueous chemical growth, in which the doping and the formation of nanorods occurred simultaneously (i.e., in situ doping). These samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet (UV)–visible spectrophotometry, linear sweep voltammetry and Mott–Schottky (M–S) measurement. Results showed that the introduction of 5% Co or Ni into α-Fe<sub>2</sub>O<sub>3</sub> (the molar ratio of dopant to Fe is 1:20) did not change its crystal phase, morphology, energy gap and flat band potential. Both the undoped and the doped α-Fe<sub>2</sub>O<sub>3</sub> showed a direct band gap of 2.24 eV, an indirect band gap of 1.85 eV, and a flat band potential of −0.22 V vs. saturated calomel electrode (SCE). At an applied potential of 0.2 V vs. SCE, the Co-doped and the Ni-doped α-Fe<sub>2</sub>O<sub>3</sub> exhibited a photocurrent of 1.28 mA/cm<sup>2</sup> and 0.79 mA/cm<sup>2</sup>, respectively, which were 2.1 times and 1.3 times that of the undoped α-Fe<sub>2</sub>O<sub>3</sub>. After the Co or Ni doping, the charge carrier concentration increased from 1.65 × 10<sup>25</sup> m<sup>−3</sup> to 3.74 × 10<sup>25</sup> m<sup>−3</sup> and 2.50 × 10<sup>25</sup> m<sup>−3</sup>, respectively. Therefore, the increase in the photocurrent of the doped α-Fe<sub>2</sub>O<sub>3</sub> was likely attributed to their enhanced conductivity. |
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| spelling | doaj.art-16032ee3b839446585165b9756ba59472023-11-20T01:13:36ZengMDPI AGApplied Sciences2076-34172020-05-011010356710.3390/app10103567Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod ArraysFeng Cheng0Xiuwei Li1School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, ChinaSchool of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, ChinaCo-doped and Ni-doped hematite (α-Fe<sub>2</sub>O<sub>3</sub>) nanorod arrays were prepared on fluorine-doped tin oxide (FTO) conductive glass via aqueous chemical growth, in which the doping and the formation of nanorods occurred simultaneously (i.e., in situ doping). These samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), ultraviolet (UV)–visible spectrophotometry, linear sweep voltammetry and Mott–Schottky (M–S) measurement. Results showed that the introduction of 5% Co or Ni into α-Fe<sub>2</sub>O<sub>3</sub> (the molar ratio of dopant to Fe is 1:20) did not change its crystal phase, morphology, energy gap and flat band potential. Both the undoped and the doped α-Fe<sub>2</sub>O<sub>3</sub> showed a direct band gap of 2.24 eV, an indirect band gap of 1.85 eV, and a flat band potential of −0.22 V vs. saturated calomel electrode (SCE). At an applied potential of 0.2 V vs. SCE, the Co-doped and the Ni-doped α-Fe<sub>2</sub>O<sub>3</sub> exhibited a photocurrent of 1.28 mA/cm<sup>2</sup> and 0.79 mA/cm<sup>2</sup>, respectively, which were 2.1 times and 1.3 times that of the undoped α-Fe<sub>2</sub>O<sub>3</sub>. After the Co or Ni doping, the charge carrier concentration increased from 1.65 × 10<sup>25</sup> m<sup>−3</sup> to 3.74 × 10<sup>25</sup> m<sup>−3</sup> and 2.50 × 10<sup>25</sup> m<sup>−3</sup>, respectively. Therefore, the increase in the photocurrent of the doped α-Fe<sub>2</sub>O<sub>3</sub> was likely attributed to their enhanced conductivity.https://www.mdpi.com/2076-3417/10/10/3567photoelectrochemical water splittinghydrogen productionaqueous chemical growthhematite nanorodin-situ doping |
| spellingShingle | Feng Cheng Xiuwei Li Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays Applied Sciences photoelectrochemical water splitting hydrogen production aqueous chemical growth hematite nanorod in-situ doping |
| title | Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays |
| title_full | Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays |
| title_fullStr | Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays |
| title_full_unstemmed | Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays |
| title_short | Effects of In Situ Co or Ni Doping on the Photoelectrochemical Performance of Hematite Nanorod Arrays |
| title_sort | effects of in situ co or ni doping on the photoelectrochemical performance of hematite nanorod arrays |
| topic | photoelectrochemical water splitting hydrogen production aqueous chemical growth hematite nanorod in-situ doping |
| url | https://www.mdpi.com/2076-3417/10/10/3567 |
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