Tailoring wettability and photocatalytic properties of NiO nanosystems fabricated by plasma-assisted vapor deposition

Thin films and nanomaterials of p-type nickel(II) oxide are attractive candidates for a plethora of technological end-uses, among which heterogeneous (photo)catalysts for various applications and hydrophobic coatings for protection against corrosion, yielding also anti-fouling, self-cleaning, and frost prevention properties [1,2].

In this work, phase-pure NiO supported nanostructures were fabricated via an original plasma assisted-chemical vapor deposition (PA-CVD) on glassy substrates at temperatures of 100°C, the lowest ever reported for similar processes, starting from a second-generation precursor, Ni(tfa)₂TMEDA (Htfa = 1,1,1-trifluoro-2,4-pentanedione; TMEDA = N,N,N’,N’-tetramethylethylenediamine) [3]. Variations of the sole process duration from 10 to 90 minutes allowed to modulate the system morphology, and, in particular, grain dimensions and deposit thickness. The control of the latter enabled to tailor the ultimate functional performances in terms of wettability and photocatalytic degradation of aqueous diclofenac {DCF = 2-[2-(2,6-dichloroanilino)phenyl]acetic acid}, a recalcitrant pharmaceutical pollutant. Material behavior is discussed in relation to material structure, composition and morphology, investigated based on a comprehensive characterization performed by complementary analytical tools. The present outcomes open the door to the fabrication of NiO nanostructures with modular features even on thermally sensitive substrates for a variety of functional applications.

[1] D. Barreca, E. Scattolin, C. Maccato, A. Gasparotto, L. Signorin, N. El Habra, A. Šuligoj, U. Lavrenčič Štangar, G.A. Rizzi, Chem. Commun., 2025, 61, 2945.

[2] D. Barreca C. Maccato, A. Gasparotto, G.A. Rizzi, Surf. Sci. Spectra, 2025, 32, 024005.

[3] M. Benedet, D. Barreca, E. Fois, R. Seraglia, G. Tabacchi, M. Roverso, G. Pagot, C. Invernizzi, A. Gasparotto, A.A. Heidecker, A. Pöthig, E. Callone, S. Dirè, S. Bogialli, V. Di Noto, and C. Maccato, Dalton Trans., 2023, 52, 10677.