Two-Dimensional Graphitic Carbon Nitride for Improving the Performance of Organic Solar Cells

Organic solar cells (OSCs) have attracted lots of attentionowingto their low cost, lightweight, and flexibility properties. Nowadays,the performance of OSCs is continuously improving with the developmentof active layer materials. However, the traditional hole transportlayer (HTL) material Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)(PEDOT:PSS) presents insufficient conductivity and rapid degradation,which decreases the efficiency and stability of OSCs. To conquer thechallenge, the two-dimensional (2D) graphitic carbon nitride (g-C3N4) nanomaterials incorporated into the PEDOT:PSSas hybrid HTL are reported. The addition of g-C3N4 into PEDOT:PSS enables the thickness of the HTL to decrease forenhancing the transmittance of the film and increase the conductivityof PEDOT:PSS. Thus, the device exhibts improved charge transport andsuppressed carrier recombination, leading to the increase in short-circuitcurrent density and power conversion efficiency of the devices. Thiswork demonstrates that the incorporation of 2D g-C3N4 into PEDOT:PSS for D18:Y6 and PM6:L8-BO-based OSCs can significantlyimprove the device efficiency to 17.48% and 18.47% with the enhancementof 7.04% and 8.46%, respectively.