Polymer/quantum dot nanostructures in remarkably stabilized photovoltaics based on polymers having benzodithiophene/naphthothiadiazole constituents

Supramolecular structures were developed by the graphene and carbon quantum dots (GQD and CQD) and poly[benzodithiophene-bis(decyltetradecyl-thien) naphthothiadiazole] (PBT-DNT) short/long chains. The pre-developed quantum dot (QD)/conjugated polymer-based supramolecules were used as promoting agents of efficacy and stability in the PBT-DNT:[6,6]-phenyl C71 butyric acid methyl ester (PC71BM) photovoltaics. Air aging experiments were carried out in 38% humidity at 36 degrees C within the time periods of 0 to 90 days with 1 month intervals. The CQD and GQD nanoparticles and their associated structures by PBT-DNT long backbone did not conspicuously alter the performance and stability of PBT-DNT:PC71BM systems. Within 3 months aging, the power conversion efficiencies fell down from 3.81% to 0.18% for CQD/PBT-DNT long chain and from 4.33% to 0.17% for GQD/PBT-DNT long chain-based systems. In contrast, the patterned GQD/PBT-DNT short chain and CQD/PBT-DNT short chain supramolecules properly played their roles and reflected the best non-aged (5.57% (342 omega cm(2)) and 4.59% (486 omega cm(2))) and 90-day aged (2.01% (764 omega cm(2)) and 1.00% (835 omega cm(2))) photovoltaics. Shorter backbones had a better chance to be arranged onto the QD nanoparticles. The GQD-based nano-hybrids acted better than the CQD-based ones. It could be assigned to the flat and disc-like structure of GQDs, which facilitated assembling of the conjugated chains via pi stacking.