Fabrication of p-NiO/n-TiO 2 nano-tube arrays photoelectrode and its enhanced photocatalytic performance for degradation of 4-chlorphenol

Free-standing TiO2 nanotubes decorated with spherical nickel nanoparticles as a cost-efficient electrocatalyst for oxygen evolution reaction

“…Regarding the oxygen spectra, the registered signal is composed of three bands with maxima found at 531.7 eV, 530.2 eV and 528.9 eV. The prominent one is attributed to the oxygen found in the titania lattice (Ti–O) 24 while the peak located at the highest binding energy is assigned to the oxygen present in hydroxyl groups 25 or some irreversibly adsorbed water molecules onto the material surface. 26 The last signal arises due to the Ni–O bond present in nickel oxide as was also reported by Yu et al 24 and Guo et al 26 .…”

Enhanced visible-light-photoconversion efficiency of TiO2 nanotubes decorated by pulsed laser deposited CoNi nanoparticles

“…Another explanation could be that CoO absorbs photons in the visible, due to its narrow band gap (e.g.,~2.4 eV) and actively participate to photo-electrochemical reaction [54]. NiO semiconductor has a larger bandgap (e.g.,~3.5 eV) [19], and couldn't be responsible of this enhanced activity in the visible. Under visible light, the photo-electrochemical activity enhancement ε vis of CoNi-NPs deposited under O 2 (red curve in Fig.…”

“…Since the CoNi-NPs deposited under O 2 are likely fully oxidized, one would expect a beneficial contribution from the CoO for the harvesting of visible photons that would not be otherwise photoconverted by TiO 2 . Another phenomenon that can be involved in the significant increase of ε under solar illumination could be the formation of a heterojunction between NiO/ CoO nanoparticles and TiO 2 nanotubes [19,55,56]. The photoelectrochemical water-splitting reaction relies on 3 steps: (i) absorption of photons leading to electron-hole pair formation, (ii) photogenerated carriers separation and (iii) interface oxydo-reduction reactions.…”

“…Currently, many efforts are devoted to develop low-cost and effective catalysts. Decoration with transition metals oxydes such as MnO 2 [18], NiO [19] or CoO [20] have been investigated as co-catalysts for the OER reaction. Recently, Cheng et al have investigated photocatalytic performances of TiO 2 nanotubes (NTs) decorated with NiO nanoparticles (NPs), prepared by an electrodeposition method.…”

Photocatalytic activity of Yb, Er, Ce‐codoped TiO2 for degradation of Rhodamine B and 4‐chlorophenol

“…It is known that the photocurrent decay resulted from the recombination processes. A steady‐state current is established through the recombination and the charge carrier generation reaches equilibrium . The high photocurrent response of the TiO 2 –Er 0.15 Yb 0.15 Ce 0.14 sample suggests that it possesses better photo‐induced charge separation efficiency for the existence of heterojunction structure.…”