ZnO-nanowire and nanoparticles are used for the photonics, solar cells, and photovoltaic devices, and the composites were characterized. ZnO-nanowire, ZnO-nanoparticles, and Cdots were synthesized by hydrothermal, polyol solvent, and hydrothermal methods, respectively. ZnO nanowires and nanoparticles have been evaluated the effects of added carbon dots (C-dots) on the performance of photovoltaic devices. The photovoltaic conversion of dye-sensitized solar cells (DSSCs) was effective for ZnO NW/ZnO NP (75 wt%) and the incorporation of 10 wt% Cdots in the hybrid nanostructures. Additionally, when the mole ratio (ethylene diamine: citric acid) between raw materials of C-dots was 1:2, the conversion efficiency was highest, and this value was 6 times higher than that of DSSCs ZnO NW/ZnO NP (75 wt%) without C-dots. Electrochemical impedance spectroscopy also indicated that the charge transfer resistance property was lowest for Cdots (1:2)-hybridized ZnO NW/ZnO NP (75 wt%) DSSCs.