Effect of hydrogen doping on the loading of titania nanotube films with copper selenide species via alternating current deposition

Abstract

Fabrication of TiO 2 nanotube (TiNT) films nicely decorated with lower band gap semiconducting nanoparticles remains a challenging issue for photocatalytic and solar cell applications active under visible light irradiation. In this study, TiNT films were decorated with copper selenide species via alternating current deposition method. For the first time, to achieve uniform loading of copper selenide species inside the TiNT film, as-grown and calcined TiNT films before depositions were subjected to hydrogen doping in various solutions under DC and AC pretreatments as well as by treating TiNT in H 2 atmosphere. Different pretreatments resulted in different architectures of Cu x Se-in-TiNT formed by subsequent AC deposition from the acidic Cu(II)-H 2 SeO 3 solution allowing predictable to encase Cu 2 Se 3 , Cu 2 Se, CuSe, or Cu 2-x Se species in nm-scaled size. Field-emission scanning electron microscopy with EDS and X-ray mapping, low-angle X-ray diffraction, and diffuse reflectance spectroscopy were applied to characterize the morphology, composition, uniformity of loading, and optical properties of the fabricated heterostructures. Except light absorption, characteristic for anatase TiO 2 , the additional absorption edge in the visible region is formed in the TiNT films decorated with copper selenide.

Substrate Impact on the Structure and Electrocatalyst Properties of Molybdenum Disulfide for HER from Water

“…Electrolytic property robustness was confirmed by more than 15 h continuous HER processing in an acidic solution. The good catalytic activity and stability of MoS2 films hybridized with aniline at the Ti/TiO2 substrate was also confirmed by invariable values of the A1g (410 cm −1 ) and E2g 1 (383 cm −1 ) vibrational modes characteristic to MoS2 Raman spectra [51] (Figure 8b) and could be explained not only by the nanotubed morphology and chemical affinity of MoS2 to titania surface as has been reported [48,51] but also by the low Ti/TiO2 interface resistance occurring via hydrogen spilt over effect [52,53]. Titanium substrates covered with nanostructured titanium monoxide, particularly TiOx nanofeatures, were also tested.…”

Hydrothermal synthesis and characterization of nanostructured titanium monoxide films

“…6 To tune the absorption edge of TiO 2 in the visible light region, the doping of titania with various elements both in the Ti and O sublattice positions has been proposed and discussed in numerous papers. [7][8][9][10][11][12][13] Besides, the hybridization of titania with lower bandgap semiconductor nanoparticles and quantum dots, such as Cu 2 O, 14 CuSe x , 15 CdSe, 16 etc. has been proposed.…”