氧化石墨炔提升界面电荷传输及分离以构筑高效二元有机太阳能电池器件

Graphdiyne oxide-accelerated charge carrier transfer and separation at the interface for efficient binary organic solar cells

通过界面工程调节载流子动力学是提高太阳能电池器件效率的关键方式.在本工作中,我们成功制备了具有大量官能团的高分散性氧化石墨炔(GDYO),并将其应用于优化空穴传输材料PEDOT:PSS的性质以制备有机太阳能电池器件.结果表明,GDYO与PEDOT:PSS之间的π–π相互作用有利于优化电荷转移通道,提高空穴传输层的电导率和载流子迁移率.此外,界面接触的改善有助于抑制电荷的复合,提高空穴传输层和活性层之间的电荷提取.同时,活性层的形貌得到有效改善,瞬态吸收测试结果证实这有利于载流子分离率的提升,进而提高器件性能.因此,通过对载流子动力学的系统性优化,二元有机太阳能电池的光电转换效率达到17.5%,认证效率达到17.2%.本工作结果表明功能化石墨炔在有机光电器件领域具有广阔的应用前景.

Interfacial engineering for the regulation of the charge carrier dynamics in solar cells is a critical factor in the fabrication of high-efficiency devices.Based on the successful preparation of highly dispersible graphdiyne oxide(GDYO)with a large number of functional groups,we fabricated organic solar cells employing GDYO-modified poly(3,4-ethylenedioxythiophene)/poly(styrene sulfonate)(PEDOT:PSS)as hole transport materials.Results show that theπ±πinteraction between GDYO and PEDOT:PSS is beneficial to the formation of an optimized charge carrier transfer channel and improves the conductivity and charge carrier mobility in the hole transport layer.Moreover,the improved interfacial contact contributes to the suppression of charge carrier recombination and the elevation of charge carrier extraction between the hole transport layer and the active layer.More importantly,the occurrence of charge carrier separation benefits from the optimized morphology of the active layer,which efficiently improves the performance,as proven by the results of transient absorption measurements.Therefore,with the holistic management approach to the multiobjective optimization of the charge carrier dynamics,a photoelectric conversion efficiency of 17.5%(with the certified value of 17.2%)is obtained for binary organic solar cells.All of these results indicate the potential application of the functionalized graphdiyne in the field of organic optoelectronic devices.