Efficient Dye-Sensitized Solar Cells (DSSCs) via Nitrogen PlasmaEnriched Chitosan@PVA@rGO Blend-Based Counter Electrode Compositions

Dye-sensitized solar cells (DSSCs) present a promising solution for renewable energy due to their affordability, versatility,
and sustainability, which are crucial in addressing climate change. This study explores the enhancement of low-cost, platinum-free counter-electrodes (CEs) for DSSCs through nitrogen (N2) plasma treatment, aimed at increasing photon absorption and the creation of active sites for improved efficiency. For the first time, Chitosan@PVA@rGO (CPG) hybrid films
were developed as CE material and exposed to in-situ N2-plasma modification levels (0, 1, 2, 3, and 4 min) to optimize
their microstructural and physiochemical properties. Comprehensive evaluations, including J–V characteristic analysis,
microstructural, porosity, morphology, contact angle, optical, and electrochemical impedance spectroscopy (EIS) assessments, were conducted. The study reveals that increasing plasma levels progressively enhanced the surface characteristics of the CPG composites, with optimal performance observed after 3 min (73.5% porosity, roughness Ra=6.69 μm).
Notably, plasma procedure improved DSSC efficiency, reaching 6.67% after 1 min and 7.48% after 2 min. Enhanced
charge carrier mobility and reduced recombination were observed, resulting in prolonged device lifespan and efficient
charge transfer. The CPG CE achieved a peak efficiency of 9.12% and a Jsc of 19.44 mA/cm² after 3 min, marking a 40%
improvement over the pristine material. This improvement is attributed to the formation of oxygen-enriched free radicals
within the CPG structure, facilitating rapid electron transfer. This research underscores the potential of plasma surface
modification in optimizing heteroatom-doped CE materials for DSSCs, offering a novel approach to enhancing photovoltaic performance. Continued improvements in DSSC technology are going to produce a more powerful and sustainable
energy future, including current advances such as plasma treatments and their seamless integration with energy systems
for improved effectiveness and durability