Electro spun composite nanofibers of three series were prepared using different polymers (P1, P2, P3) and cadmium sulphide (CdS). Organic polymers of carbazole based quinoline (P1), quinoxaline (P2), and pyrazine (P3) hybrid with inorganic CdS nanofibers were characterized by XRD and FTIR technique. Collective arrangement of spiderweb-like morphology was observed for all nanofibers. Deviations of absorption and photoluminescence were monitored and a significant blue shift was found after doping CdS and PVA. It was found that the changes in the PL spectra of polymers originated from the chemical interactions between polymer and CdS. The diameter of nanofibers was observed as 127-347 nm from SEM analysis and 66-213 nm from TEM analysis. Optimum thermal stability of the composite nanofibers was achieved up to 200 °C. Compared with pure polymers and CdS, present nanofibers were good thermal stability, apparent blue shift with bluish emission which is suitable for optoelectronics application. © The Author(s) 2021.