Boost Organic-Silicon Hybrid Solar Cell Performances with a Facile and Cost-Effective Sub-3 nm Interface Control Method

A facile and cost-effective approach based on oxygen-plasma treatment is developed for silicon-organic hybrid solar cells. By precisely forming a sub-3 nm SiOx layer at the silicon-poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) interface with a 10 s oxygen-plasma treatment, the power conversion efficiency is boosted from 0.02% to 8.18%, 409-fold increase compared to solar cells with untreated silicon. Utilizing X-ray photoelectron spectroscopy, Kelvin probe force microscopy, and density-functional theory, the device physics and mechanisms are revealed from an atomic-level perspective. The control of interface by oxygenplasma treatment reduces the surface work function of Si and introduces an electron barrier, facilitating the transfer of hole carriers from Si to organic materials while effectively blocking electron transmission. This mechanism proves to be highly beneficial in mitigating carrier recombination and promoting the separation of electrons and holes. This approach can be applied to interface optimization for high-performance photovoltaic and other optoelectronic devices.

本研究针对硅-有机杂化太阳能电池，开发了一种基于氧等离子体处理的简便易行且高性价比的制备策略。通过10秒氧等离子体处理，在硅与聚(3,4-乙撑二氧噻吩):聚(苯乙烯磺酸盐)的界面处精准构筑了厚度小于3纳米的SiOx层，使器件的光电转换效率从0.02%提升至8.18%，相较于未处理硅基太阳能电池提升了409倍。本研究借助X射线光电子能谱（X-ray photoelectron spectroscopy）、开尔文探针力显微镜（Kelvin probe force microscopy）以及密度泛函理论（density-functional theory），从原子尺度视角揭示了该器件的物理机制与工作原理。氧等离子体处理对界面的调控，降低了硅的表面功函数并引入了电子势垒，促进空穴载流子从硅向有机材料转移，同时有效阻挡电子传输。该机制可显著抑制载流子复合并促进电子与空穴的分离。此方法可应用于高性能光伏器件及其他光电子器件的界面优化。