Photoelectrochemical (PEC) measurements used Lapatinib Ditosylate three-electrode cell to semi-quantitatively describe the defects in the coatings containing different amounts of Cr. The as-prepared samples acted as the working electrode, the platinum foil acted as the counter electrode, and the saturated calomel electrode (SCE) acted as the reference. Electrochemical signals were recorded with a universal electrochemical interface analyzer Zahner IM6e. A 100 mW/cm2 Xenon arc lamp simulated solar light in the PEC measurement. Borate buffer with pH 8.0 was used as the electrolyte. The front surface of the working electrode was sealed by epoxy leaving an area of 0.4 cm2.
2.2. Formation alumina powders via sol–gel process
To compare the dopant effect, alumina powders via sol–gel process were designed. The starting materials for hydrated alumina are negative feedback loop Al(NO3)3·9H2O and Cr(NO3)3·9H2O. These were dissolved into 80 mL of distilled water. Precursors of 0.0%Cr and 1.5%Cr were synthesized. Precursors were produced by dropping 25% (v/v) ammonia water (AW) into the solution at a low speed under magnetic stirring at room temperature. The resulting suspensions were aged for 12 h at room temperature, filtered with distilled water twice, rinsed another two times with ethyl alcohol and then dried at 100 °C for 10 h. After an intermediate grinding, the precursors were sintered at 600 °C, 900 °C, and 1000 °C for 4 h.