<p>The growing demand for sustainable energy and environmental remediation has led to the development of advanced materials with multifunctional capabilities. In this study, a spray coating process was employed to incorporate activated carbon (AC) nanoparticles onto natural rubber (NR) films, enhancing their performance as triboelectric layers in nanogenerators (TENGs) and as air filter membranes. The AC nanoparticles were dispersed in NR latex, forming a coating solution that modified the NR film surface. The effects of AC loading on the surface morphologies, TENG electrical output, dielectric properties and mechanical strength of the NR composites were investigated. The spray-coated AC-modified NR films (AC-NRF) exhibited improved surface roughness and charge-trapping properties, leading to a remarkable 225% enhancement in TENG output compared to pristine NR films, with a peak power density of 2.25&#xa0;W&#xa0;m⁻² at an optimal AC concentration of 0.75%. Additionally, the AC-NRF films demonstrated improved mechanical strength and durability, with tensile strength increasing proportionally to AC content. Due to the high surface area and porosity of AC nanoparticles, the composite films were further applied in environmental applications, exhibiting the ability to filter particulate matters (PMs) including PM_2.5 and PM₁₀, as well as to adsorb CO₂ gas. These findings highlight the potential of AC-NRF composites as multifunctional materials for energy harvesting and air purification, offering scalable solutions for sustainable development.</p> Graphical abstract <p></p>