Work function control in carbon nanosheets via chloride-based metal precursors and their applications as transparent electrodes

[Display omitted] •The work function of carbon nanosheets (CNSs) is easily controlled using various chloride-based metal precursors by the simple spin coating without post-treatment.•The work function of CNSs doped with AuCl3, ZnCl2, and CoCl2 presented values of 4.91, 4.77, and 4.69eV, respectively, which are significantly higher than that of pristine CNSs (4.60eV).•The PCE of the ITO-free OPV using metal chloride-doped CNSs increased ∼21.1% compared to that of pristine CNS due to spontaneous charge transfer between the CNSs and metal ions. Work function of carbon nanosheets (CNSs) is easily controlled using various chloride-based metal precursors. The metal ions in the precursors are reduced despite the simple spin coating without post-treatment due to electron transfer from the CNSs to the ions. The work function of CNSs doped with AuCl3, ZnCl2, and CoCl2 presented values of 4.91, 4.77, and 4.69eV, respectively, which are significantly higher than pristine CNSs (4.60eV). The reduced metal nanoparticles locally induced electronic modification of the CNSs located in the vicinity, leading to transparent conducting electrodes with high work functions and subsequently a high power conversion efficiency of ∼2.01% for an ITO-free OPV incorporating a AuCl3-doped CNS electrode.