carbon quantum dots as an effective nanomaterial for quantum dots-sensitized solar cells

In this research, nitrogen doped carbon quantum dots (n-cqds) were synthesized through pyrolysis using monoethanolamine (mea) and citric acid. the impact of thiourea (th), as the source of sulfur, was investigated on the optical properties of synthesized cqds. synthesized cqds were characterized by using ftir analysis and optical properties were investigated by uv-visible and pl spectroscopy. the results revealed that n-cqds and n,s-cqds have the absorption edge of 490 and 515 nm, respectively. in addition, excitation – dependent emission was observed in synthesized cqds through pl analysis. photoelectrical measurements revealed improvement in efficiency of the fabricated solar cells using synthesized n,s-cqds/tio2 compared to the as prepared tio2 solar cell. the results showed an improved efficiency with respect to the short-circuit current density and fill factor from 0.017 to 0.27 ma/cm2 and from 0.47 to 0.66, respectively.