Abstract:
Delafossite CuCrO
2 was prepared with Cr(NO
3)
3 and Cu(NO
3)
2 by the semi-wet method via two different routes. The samples were characterized with thermogravimetry-differential scanning calorimetry, X-ray diffraction, diffuse reflectance ultraviolet-visible spectroscopy, scanning electron microscopy and X-ray photoelectron spectroscopy techniques. It was shown that addition of Cr(OH)
3 precipitated with aqueous ammonia solution into aqueous Cu(NO
3)
2 solution is a suitable route to synthesize CuCrO
2. In the calcination process, the precursor transformed into CuCrO
2 in the sequence: Cr(OH)
3 → CuCrO
4 → CuCr
2O
4 → CuCrO
2, as verified by the TG-DSC and XRD results. The composites of CuCrO
2-WO
3 and CuCrO
2-ZnO prepared by the grinding method show higher activity than CuCrO
2 in the photocatalytic splitting of water into hydrogen under the irradiation of a high-pressure mercury lamp or a xenon lamp.