Major drawbacks of a Pt-free counter electrode in dye-sensitized solar cells (DSSCs) are low electrical conductivity and low electrocatalytic activity. One of the promising materials for use in the counter electrode in DSSCs is graphite. It is well-known that graphite provides notable electrical conductivity, but has low electrocatalytic activity. Therefore, the surface of the graphite electrode has to be covered by an electrocatalytically active material. The presence of an electrocatalytically active layer will facilitate charge transfer at the electrode–electrolyte interface. In this report, we demonstrate the combination of reduced graphene oxide (rGO) and polyaniline (PANI) to enhance the electrocatalytic activity of a graphite counter electrode. rGO is synthesized from graphite using the sonication–oxidation method followed by reduction using ascorbic acid. This technique produced two types of rGO: floated and precipitated rGOs. PANI was grown on the surfaces of dispersed rGO in a water/ethanol system using an in situ polymerization technique. This technique resulted in both low-conductivity PANI–floated rGO (PANI–FrGO) and high-conductivity PANI–precipitated rGO (PANI–PrGO). In the composite electrode, rGO acts as a bridge between the graphite surface, and polyaniline acts as the electrocatalytically active material. The highest photovoltaic performance was obtained for a cell using the graphite/PANI–PrGO composite counter electrode. This cell gives an optimal open-circuit voltage (V_oc), fill factor (FF), overall conversion efficiency (η), and short-circuit current density (J_sc) of 0.66 V, 0.508, 1.83% and 4.899 mA/cm², respectively. Measurement of photovoltaic performance was carried out under 100 mW cm⁻² of air mass (AM) 1.5 illumination. The contribution of PANI–rGO on the graphite composite counter electrode was demonstrated to enhance photovoltaic performance that opens an alternative route for the low-cost fabrication of Pt-free DSSC counter electrodes.

染料敏化太阳能电池（DSSC）中无铂对电极的主要缺点是电导率低和电催化活性低。用于DSSC中对电极的有前途的材料之一是石墨。众所周知，石墨具有显着的导电性，但电催化活性低。因此，石墨电极的表面必须被电催化活性材料覆盖。电催化活性层的存在将促进电荷在电极-电解质界面处的转移。在本报告中，我们证明了还原氧化石墨烯（rGO）和聚苯胺（PANI）的组合可增强石墨对电极的电催化活性。rGO是由石墨通过超声氧化法合成的，然后使用抗坏血酸还原。该技术产生了两种类型的rGO：漂浮的和沉淀的rGO。使用原位聚合技术，在水/乙醇系统中，将PANI生长在分散的rGO的表面上。这种技术既产生了低电导率的PANI漂浮的rGO（PANI–FrGO），也产生了高电导率的PANI沉淀的rGO（PANI–PrGO）。在复合电极中，rGO充当石墨表面之间的桥梁，而聚苯胺充当电催化活性材料。使用石墨/ PANI-PrGO复合对电极的电池获得了最高的光伏性能。该电池可提供最佳的开路电压（使用原位聚合技术，在水/乙醇系统中，将PANI生长在分散的rGO的表面上。这种技术既产生了低电导率的PANI漂浮的rGO（PANI–FrGO），也产生了高电导率的PANI沉淀的rGO（PANI–PrGO）。在复合电极中，rGO充当石墨表面之间的桥梁，而聚苯胺充当电催化活性材料。使用石墨/ PANI-PrGO复合对电极的电池获得了最高的光伏性能。该电池可提供最佳的开路电压（使用原位聚合技术，在水/乙醇系统中，将PANI生长在分散的rGO的表面上。这种技术既产生了低电导率的PANI漂浮的rGO（PANI–FrGO），也产生了高电导率的PANI沉淀的rGO（PANI–PrGO）。在复合电极中，rGO充当石墨表面之间的桥梁，而聚苯胺充当电催化活性材料。使用石墨/ PANI-PrGO复合对电极的电池获得了最高的光伏性能。该电池可提供最佳的开路电压（rGO充当石墨表面之间的桥梁，而聚苯胺充当电催化活性材料。使用石墨/ PANI-PrGO复合对电极的电池获得了最高的光伏性能。该电池可提供最佳的开路电压（rGO充当石墨表面之间的桥梁，而聚苯胺充当电催化活性材料。使用石墨/ PANI-PrGO复合对电极的电池获得了最高的光伏性能。该电池可提供最佳的开路电压（V _oc），填充系数（FF），总转换效率（η）和短路电流密度（J _sc）分别为0.66 V，0.508、1.83％和4.899 mA / cm ²。在100mW cm ^-2的空气质量（AM）1.5照度下进行光伏性能的测量。PANI–rGO在石墨复合对电极上的贡献被证明可以增强光伏性能，这为低成本制造无Pt DSSC对电极开辟了一条替代途径。