Abstract: This study explores the synthesis and characterization of a Carbon Quantum Dots (CQDs)/CdS/ZnS photoanode thin-film solar cell with a Cu-CuS counter electrode, targeting eco-friendly and efficient photovoltaic applications. The CQDs were synthesized via a hydrothermal method, while CdS and ZnS layers were deposited using the SILAR technique. The fabricated solar cell, comprising FTO/d-TiO2/m-TiO2/ CQD/CdS/ZnS/ /CuS-Cu, demonstrated a short-circuit current density (J_sc) of 26.30 µA, an open-circuit voltage (V_oc) of 0.470 V, and a power conversion efficiency (PCE) of 1.88%. The Cu-CuS counter electrode show cased desirable electronic properties, including a low resistivity (ρ) of 2.161×10^(-2) Ω⋅cm and high conductivity (σ) of 4.628×10^2 S/cm, Hall coefficient (RH) of value of 5.659 cm^3/C and sheet resistance (Rs) value of 3.087 Ω/sq. These findings suggest that incorporating green materials and innovative design can significantly contribute to sustainable energy solutions, though further optimizations are required to enhance device performance.

| DOI: 10.17148/IARJSET.2025.12224