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Electroplating of Selenium

I am a research worker. I need the selenium electroplating methodology in detail.

Thanks

Dr. Muhammad Farooq
- Lahore, PAKISTAN
2001

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June 23, 2009

Check out this procedure for making Selenium nanowires to get on the right path for this, (from 'Formation and phase transformation of selenium nanowire arrays in anodicporous alumina templates' by X.Y. Zhang, Y. Cai, J.Y. Miao, K.Y. Ng, Y.F. Chan, X.X. Zhang, N. Wang):

The anodic porous alumina templates [8] used for the electrodeposition of Se nanowires were prepared using highly pure (99.999%) aluminum foils. Prior to anodizing, the aluminum foils were annealed at 500 1C for 3 h in order to obtain homogeneous grains and reduce the defect density in the foils. This process was essential for the formation of a high quality of nanochannels in the foil during the subsequent anodization. The annealed foils were then electropolished in C2H5OH solution mixed with HClO4 (9:1 in volume) in order to obtain a high quality of flat surfaces. Then, anodization was carried out under the condition of a constant cell voltage (40 V) in a 0.3M oxalic acid solution. A 10-mm thick porous alumina template containing nanochannels formed on the foil for 2-h anodization. The nanochannels were about 50È60nm in diameter and 10 mm in length. The remaining aluminum was then removed by a saturated HgCl2 solution. The nanochannels were dredged and widened by chemical etching from both sides of the template film in aqueous solution of phosphoric acid. Before electrodeposition, a thin layer (about 100 nm) of Au electrode was coated on one side of the template. We electrodeposited Se nanowires in the channels of the template in the solution of SeO2+H2BO3 (40 g/l SeO2, 25 g/l H2BO3 and pH æ 1.5) using a potentiostatic method . Platinum was used as the counter electrode. The cathode potential was kept at 1.0V vs. the saturated calomel electrode (SCE). The lengths of Se nanowires were controlled by the deposition time. The color of the template containing Se nanowires was orange at the initial stage of the deposition and then became dark gray at the end of the deposition. The as-grown samples were dried and then annealed at various temperatures. Freestanding Se nanowires were obtained by etching away the alumina template in phosphoric acid solution (6 wt%) mixed with chromic acid (1.8 wt%). Their morphology and microstructures were investigated using a Philips XL30 scanning electron microscope (SEM) and a JEOL-2010 transmission electron microscope (TEM) operating at 200 kV. The Raman spectra were measured by a Renishaw RM3000 Raman spectrometer equipped with an argon laser (wavelength 514.5 nm and output power 20 mW). The high-resolution TEM image simulations were carried out using the JEMS program of CIME-EPFL (Bloch wave method).

Arianne Saunders
Ohio University - Athens, Ohio, USA