Boosting the electrical properties of nano-structured (Ga ₁₀ Se ₉₀ )-MWCNT bilayer thin films

Selenium-based chalcogenide semiconductors are of growing interest for optoelectronic applications due to their high DC conductivity, photoconductivity, and carrier mobility. In this work, Ga₁₀Se₉₀-MWCNT nanocomposite thin films were fabricated <i>via</i> thermal evaporation and subsequently modified using swift heavy ion (SHI) irradiation using 70 MeV Ni⁷⁺ ions at fluences of 1 × 10¹² to 1 × 10¹³ ions per cm². SHI irradiation promoted the homogeneous mixing of CNTs within the GaSe matrix, enhancing the electrical properties through defect engineering and interfacial charge transfer. Characterization <i>via</i> FESEM, EDX, and FTIR confirmed uniform nanoparticle dispersion and strong GaSe-CNT interactions. Post-irradiation, DC conductivity increased from 2.11 × 10^-4 to 2.97 × 10^-3 Ω^-1 cm^-1, photoconductivity from 5.16 × 10^-5 to 2.90 × 10^-3 Ω^-1 cm^-1, and carrier mobility from 50.9 to 475.1 cm² V^-1 s^-1. These enhancements are attributed to improved charge transport <i>via</i> CNT networks and SHI-induced acceptor states. The results highlight the tunability of GaSe-CNT composites <i>via</i> SHI, supporting their potential use in advanced optoelectronic devices.