In this work, we report a graphene-alkaline lignin-poly(3,4-ethylenedioxythiophene) polystyrene sulfonate composite as a transparent conductive electrode for indium tin oxide-free optoelectronic devices. The composite was prepared by dispersing exfoliated graphene-alkaline lignin into aqueous poly(3,4-ethylenedioxythiophene) polystyrene sulfonate. The effect of graphene concentration on the electrical and optical properties of graphene-alkaline lignin-poly(3,4- ethylenedioxythiophene) polystyrene sulfonate was studied. The graphene-alkaline lignin-poly(3,4- ethylenedioxythiophene) polystyrene sulfonate thin films exhibit excellent electrical conductivity and high transparency properties. The electrical conductivity is further increased by 1.9 ± 0.01 × 10³ times when graphene content was augmented in the composites; however, the optical transparency was reduced due to the high optical absorbance of graphene. In this condition, the conductivity and optical transparency are as high as (4.19 ± 0.01) × 10³ S/cm and 94.2%, respectively. This achievement is attributed to the organization of higher ordered network between conductive exfoliated graphene and poly(3,4-ethylenedioxythiophene) chains that induced a better conducting channel for charge transportation. The poly(3,4-ethylenedioxythiophene) chains act as a bridge connecting the graphene flakes, which, in turn, facilitate the movement of hole charges between them.

在这项工作中，我们报告了石墨烯-碱性木质素-聚（3,4-乙撑二氧噻吩）聚苯乙烯磺酸盐复合材料，作为无铟锡氧化物光电器件的透明导电电极。通过将剥离的石墨烯-碱性木质素分散到聚（3,4-乙撑二氧噻吩）聚苯乙烯磺酸水溶液中来制备复合材料。研究了石墨烯浓度对石墨烯-碱性木质素-聚（3,4-乙撑二氧噻吩）聚苯乙烯磺酸盐的电学和光学性质的影响。石墨烯-碱性木质素-聚（3,4-乙撑二氧噻吩）聚苯乙烯磺酸盐薄膜具有优异的导电性和高透明性。电导率进一步提高1.9±0.01×10 ³复合材料中石墨烯含量增加的次数；但是，由于石墨烯的高吸光度，光学透明性降低。在这种条件下，电导率和光学透明度分别高达（4.19±0.01）×10 ³ S / cm和94.2％。该成就归因于导电剥落石墨烯与聚（3,4-乙撑二氧噻吩）链之间的较高序网络的组织，该链诱导了更好的电荷传输导电通道。聚（3,4-乙撑二氧噻吩）链充当连接石墨烯薄片的桥，进而促进了空穴电荷在它们之间的移动。