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In the following article, we present a simple, two-step method of creating spaced, hollow nanopillars, from the titania nanotube arrays via pulsed laser-treatment. Due to the high ordering of the structure, the prepared material exhibits photonic properties, which has been shown to increase the overall photoefficiency. The optical and morphological changes in the titania nanotubes after pulsed laser-treatment with 532, 355, and 266 nm wavelengths in the 10–50 mJ/cm2 fluence range are studied. The investigation reveals, that by using appropriate wavelength and energy, the number of surface defects, geometrical features, or both can be tailored.

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The selective, laser‐induced modification of the nickel‐decorated titania nanotubes provides remarkable enhancement toward oxygen evolution reaction. Particularly, the irradiation of the laterally spaced crystalline TiO2 nanotubes, results in the formation of the tight closure over irradiated end, preserving their hollow interior. The shape of the absorbance spectra is modulated along with applied energy, and the new absorption band appears at 500 nm, where the local minimum can be found for bare nanotubes. The high‐resolution X‐ray photoelectron spectra indicate the presence of both metallic and hydroxide forms of nickel species. The electrode material treated with 355 nm pulses at 50 mJ cm−2 shows significantly improved current densities in the anodic regime, reaching nearly 300 mA cm−2 while exposed to solar radiation, whereas the untreated sample barely comes to 1.5 mA cm−2 in the same conditions. The tailored titania photoanode also exhibits two orders of magnitude higher donor concentration in comparison to the primary substrate as verified by Mott–Schottky analysis. The electrochemical analysis confirms the key role of laser annealing in enhancing the effectiveness of light‐driven water splitting.

Fossil fuels became increasingly unpleasant energy source due to their negative impact on the environment; thus, attractiveness of renewable, and especially solar energy, is growing worldwide. Among others, the research is focused on smart combination of simple compounds towards formation of the photoactive materials. Following that, our work concerns the optimized manipulation of laser light coupled with the iron sputtering to transform titania that is mostly UV-active, as well as exhibiting poor oxygen evolution reaction to the material responding to solar light, and that can be further used in water splitting process. The preparation route of the material was based on anodization providing well organized system of nanotubes, while magnetron sputtering ensures formation of thin iron films. The last step covering pulsed laser treatment of 355 nm wavelength significantly changes the material morphology and structure, inducing partial melting and formation of oxygen vacancies in the elementary cell. Depending on the applied fluence, anatase, rutile, and hematite phases were recognized in the final product. The formation of a re-solidified layer on the surface of the nanotubes, in which thickness depends on the laser fluence, was shown by microstructure studies. Although a drastic decrement of light absorption was recorded especially in UV range, laser-annealed samples have shown activity under visible light even 20 times higher than bare titania. Electrochemical analysis has shown that the improvement of photoresponse originates mainly from over an order of magnitude higher charge carrier density as revealed by Mott-Schottky analysis. The results show that intense laser light can modulate the semiconductor properties significantly and can be considered as a promising tool towards activation of initially inactive material for the visible light harvesting.