Effects of Adsorption of Submonolayer Cs Coatings on the Electronic Structure and Physical Properties of NiO and MoO₃
Abstract
Using methods for measuring the dependence of the true secondary electron yield δ on the primary electron energy Ep, as well as Auger-electron and photoelectron spectroscopy, the effects of Cs deposition with thickness θ from 0.2 to 4 monolayers on the composition, valence-electron density of states, and energy-band parameters of NiO and MoO₃ films were studied. It is shown that at θ = 1 monolayer (ML), the largest decrease in the electron affinity χ, the largest increase in the secondary electron yield δ, and the photoelectron quantum yield Y occur. At the same time, the band gap width Eg and the positions of peaks in the valence-electron spectra remain practically unchanged. It was shown for the first time that, for NiO, at θ = 1 ML, the surface electron affinity χ approaches zero. It is found that at θ > 1 ML, changes in the composition, structure, emission, and optical properties of the Cs–NiO system begin to be influenced by the thickness of the Cs film.
Downloads
References
T.U. Devi, E.R. Kumar, M. Kumar, B. Balraj, Ch. Sivakumar, P. Matheswaran, N. Chandrasekar, et al., “Physicochemical properties and photocatalytic activity of MoO₃ nanostructures: evaluation of structural, optical, vibrational, and morphological properties,” Ceram. Int. 49, 13994–14006 (2023). https://doi.org/10.1016/j.ceramint.2022.12.281
D.K. Halwar, V.V. Deshmane, and A.V. Patil, “The combination of nickel oxide (NiO) and molybdenum trioxide (MoO₃) for pollutant gas detection,” J. Electron. Mater. 52, 1840–1853 (2023). https://doi.org/10.1007/s11664-022-10130-x
N.G. Prakash, M. Dhananjaya, A.L. Narayana, D.P.M.D. Shaik, P. Rosaiah, and O.M. Hussain, “High-performance one-dimensional α-MoO₃ nanorods for supercapacitor applications,” Ceram. Int. 44, 9967–9975 (2018). https://doi.org/10.1016/j.ceramint.2018.03.032
P.A. Dement’ev, E.V. Ivanova, M.N. Lapushkin, D.A. Smirnov, and S.N. Timoshnev, “Electronic structure of molybdenum oxidized in air,” Phys. Solid State, 61, 1993–1998 (2019). https://doi.org/10.1134/S1063783419110131
F. Ma, Y. Zhao, J. Li, X. Zhang, H. Gu, and J. You, “Nickel oxide for inverted structure perovskite solar cells,” J. Energy Chem. 52, 393–411 (2021). https://doi.org/10.1016/j.jechem.2020.04.027
M.M. Uplane, S.H. Mujawar, A.I. Inamdar, P.S. Shinde, A.C. Sonavane, and P.S. Patil, “Structural, optical, and electrochromic properties of nickel oxide thin films grown from electrodeposited nickel sulphide,” Appl. Surf. Sci. 253, 9365 9371 (2007). https://doi.org/10.1016/j.apsusc.2007.05.069
H. Sato, T. Minami, S. Takata, and T. Yamada, “Transparent conducting p-type NiO thin films prepared by magnetron sputtering,” Thin Solid Films, 236, 27–31 (1993). https://doi.org/10.1016/0040-6090%2893%2990636-4
M. Bonomo, “Synthesis and characterization of NiO nanostructures: A review,” J. Nanopart. Res. 20, 222 (2018). https://doi.org/10.1007/s11051-018-4327-y
H.P. Parkhomenko, M.N. Solovan, and P.D. Maryanchuk, “Electrical properties of p-NiO/n-Si heterostructures based on nanostructured silicon,” Semiconductors, 52, 859–863 (2018). https://doi.org/10.1134/S1063782618070163
M.B. Rammal, and S. Omanovic, “Synthesis and characterization of NiO, MoO₃, and NiMoO₄ nanostructures through a green facile method and their potential use as electrocatalysts for water splitting,” Mater. Chem. Phys. 255, 123570 (2020). https://doi.org/10.1016/j.matchemphys.2020.123570
P.H. Silva, D.T. Cestarolli, and E.M. Guerra, “Band gap values and structural changes in MoO₃ obtained by ion-exchange method,” Opt. Mater. 164, 117063 (2025). https://doi.org/10.1016/j.optmat.2025.117063
E. Pavoni, M.G. Modreanu, E. Mohebbi, D. Mencarelli, P. Stipa, E. Laudadio, and L. Pierantoni, “First-principles calculation of MoO₂ and MoO₃ electronic and optical properties compared with experimental data,” Nanomaterials, 13, 1319 (2023). https://doi.org/10.3390/nano13081319
A. Özkartal, and D.T. Noori, “Effects of thermal annealing on the characterization of p-NiO/n-GaAs heterojunctions produced by thermal evaporation,” J. Mater. Sci.: Mater. Electron. 32, 13462–13471 (2021). https://doi.org/10.1007/s10854-021-05924-4
R. Senthilkumar, G. Anandhababu, T. Mahalingam, and G. Ravi, “Photoelectrochemical study of MoO₃ films with assorted morphologies formed by thermal evaporation,” J. Energy Chem. 25, 798–804 (2016). https://doi.org/10.1016/j.jechem.2016.04.005
D. Parviz, M. Kazemeini, A.M. Rashidi, et al., “Synthesis and characterization of MoO₃ nanostructures by solution combustion method employing morphology and size control,” J. Nanopart. Res. 12, 1509–1521 (2010). https://doi.org/10.1007/s11051-009-9727-6
B. Miao, W. Zeng, L. Lin, and Sh. Xu, “Characterization and gas-sensing properties of NiO nanowires prepared through the hydrothermal method,” Physica E, 52, 40–45 (2013). https://doi.org/10.1016/j.physe.2013.03.006
J.-K. Song, J.-S. Ahn, and E.-M. Han, “Characteristics of perovskite solar cells with a nanostructured MoO₃ hole transport layer prepared by hydrothermal synthesis,” Korean J. Mater. Res. 30, 81–86 (2020). https://doi.org/10.3740/MRSK.2020.30.2.81
M.Ch. Fite, S.D. Karse, and L.M. Gode, “Optical and photocatalytic properties of nickel oxide nanoparticles,” J. Cryst. Growth, 660, 128163 (2025). https://doi.org/10.1016/j.jcrysgro.2025.128163
P.M. Ponnusamy, S. Agilan, N. Muthukumarasamy, T.S. Senthil, G. Rajesh, M.R. Venkatraman, and D. Velauthapillai, “Structural, optical, and magnetic properties of undoped NiO and Fe-doped NiO nanoparticles synthesized by a wet chemical process,” Mater. Charact. 114, 166–171 (2016). https://doi.org/10.1016/j.matchar.2016.02.020
S. Kakherskyi, R. Pshenychnyi, O. Dobrozhan, et al., “Structural, microstructural, chemical, and optical properties of NiO nanocrystals and films obtained by 3D printing,” Appl. Phys. A, 127, 715 (2021). https://doi.org/10.1007/s00339-021-04847-5
B.G. Bharate, “Synthesis of molybdenum oxide nanoparticles by the sol–gel method for ammonia gas sensing,” Biomed. J. Sci. Tech. Res. 37, 29172–29175 (2021). https://doi.org/10.26717/BJSTR.2021. 37.005957
N. Mebrouki, S.B. Hamida, L. Benmebrouk, R. Gheriani, and L. Zenkhri, “Synthesis and characterization of nickel oxide thin films by spray pyrolysis: effect of nickel source nature,” Asian J. Res. Chem. 15, 159–162 (2022). https://doi.org/10.52711/0974-4150.2022.00026
F. Chandoul, A. Boukhachem, F. Hosni, H. Moussa, M.S. Fayache, M. Amlouk, and R. Schneider, “Change in the properties of nanostructured MoO₃ thin films under gamma-ray irradiation,” Ceram. Int. 44, 12483–12490 (2018). https://doi.org/10.1016/j.ceramint.2018.04.040
G.X. Allayarova, D.A. Tashmukhamedova, R. Djabbarganov, and B.E. Umirzakov, “Formation of nanoscale MoO₃ films by thermal oxidation and ion bombardment,” J. Surf. Investig. 15, 81–84 (2021). https://doi.org/10.1134/S1027451021010043
S. Boulila, M. Ghamnia, A. Boukhachem, et al., “Photocatalytical properties of Ba-doped NiO nanofilms,” Philos. Mag. Lett. 100, 283–293 (2020). https://doi.org/10.1080/09500839.2020.1760389
D.A. Tashmukhamedova, and M.B. Yusupjanova, Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques. 15(5), 1054-1057 (2021). https://doi.org/10.1134/S1027451021050402
Y. Aoun, M. Marrakchi, S. Benramache, et al., “Preparation and characterization of monocrystalline Na-doped NiO thin films,” Mater. Res. 21, e20170681 (2018). https://doi.org/10.1590/1980-5373-mr-2017-0681
B.E. Umirzakov, D.A. Tashmukhamedova, S.T. Gulyamova, et al., Effect of Ba⁺ ion implantation on the composition and electronic properties of MoO₃/Mo(111) films,” Tech. Phys. 65, 795–798 (2020). https://doi.org/10.1134/S1063784220050242
D.A. Tashmukhamedova, M.B. Yusupjanova, G.Kh. Allayarova, and B.E. Umirzakov, “Crystal structure and band gap of nanoscale phases of Si formed at various depths of the near-surface region of SiO2,” Technical Physics Letters, 46(10), 972 975 (2020). https://doi.org/10.1134/S1063785020100144
Sh. Wang, and A.J.R. Hensley, “Dopant effects on the environment-dependent chemical properties of NiO(100) surfaces,” Appl. Surf. Sci. 682, 161679 (2025). https://doi.org/10.1016/j.apsusc.2024.161679
Kh.Kh. Boltaev, D.A. Tashmukhamedova, and B.E. Umirzakov, “Structure and electronic properties of nanoscale phases and nanofilms of metal silicides produced by ion implantation in combination with annealing,” Journal of Surface Investigation, X_ray, Synchrotron and Neutron Techniques, 8(2), 326–331 (2014). https://doi.org/10.1134/S1027451014010108
Y.S. Ergashov, D.A. Tashmukhamedova, F.G. Djurabekova, and B.E. Umirzakov, “Effect of surface microroughness on the composition and electronic properties of CdTe/Mo(111) films,” Bulletin of the Russian Academy of Sciences: Physics, 80(2), 138 (2016). https://doi.org/10.3103/S1062873816020064
B. E. Umirzakov, D. A. Tashmukhamedova, M. K. Ruzibaeva, et al., “Investigation of change of the composition and structure of the CaF2/Si films surface at the low-energy bombardment,” Nucl. Instr. and Meth. B. 326, 322–325 (2014). https://doi.org/10.1016/j.nimb.2013.10.094
D.A. Tashmukhamedova, “Study of composition and electronic structure of CoSi2/Si interface” Bulletin of the Russian Academy of Sciences: Physics 70(8), 1409-1411. (2006). https://elibrary.ru/item.asp?id=27854241
M.B. Yusupjonova, D.A. Tashmukhamedova, B.E. Umirzakov, S.S. Pak, Z.R. Saidakhmedova, and Sh.K. Salieva, “Influence of implantation of active metal ions on the composition, emission and optical properties of MgO films,” East European Journal of Physics, (1), 260-264 (2025). https://doi.org/10.26565/2312-4334-2025-1-29
Copyright (c) 2026 A.U. Xujaniyazova, D.A. Tashmukhamedova, B.E. Umirzakov, M.B. Yusupjonova, Z.R. Saidakhmedova, Sh.K. Salieva

This work is licensed under a Creative Commons Attribution 4.0 International License.
Authors who publish with this journal agree to the following terms:
- Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a Creative Commons Attribution License that allows others to share the work with an acknowledgment of the work's authorship and initial publication in this journal.
- Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgment of its initial publication in this journal.
- Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See The Effect of Open Access).


