利用金與氧化石墨烯之奈米複合材料之侷域性表面電漿共振效應增強有機太陽能電池效率

Abstract

本研究中我們還原生成金奈米粒子(Au NPs)使其附著在石墨烯氧化物(Graphene Oxide)上，並利用PEG-SH修飾Au NPs，從場發射穿透式電子顯微鏡、原子力顯微鏡量測結果可以得知，修飾後Au NPs均勻分散在片狀石墨烯氧化物表面。接著我們將Au NP/GOs此奈米複合材料作為有機太陽能中電洞傳輸層 (hole transport layer，HTL)，利用金奈米粒子引發局部表面電漿共振，以提升元件的能量轉換效率。我們發現利用金及氧化石墨烯奈米複合材料作為HTL之元件與單純使用GO作為HTL之元件相比，元件的開路電壓並未改變，而短路電流、填充因子、能量轉換效率則有明顯的提升，其中開路電壓為0.57V，短路電流密度為10.44 mA/cm^2，填充係數可達0.67，而功率轉換效率可達到3.98%。

In this study, we used gold nanoparticle-decorated graphene oxides (AuNP/GOs) nanocomposites as the hole transport layer (HTL) in organic solar cells. We reduced gold ions to Au NPs by sodium citrate and the resulting Au NPs were adhered to the surface of GOs. In order to avoid aggregation of the Au NPs, the surface of the nanoparticles were further modified by thiol-ligands. The AuNP/GO nanocomposites were further characterized by transmission electron microscopy, atomic force microscopy and X-ray photoelectron spectroscopy. Organic photovoltaic devices (OPVs) containing Au NP/GOs composites as the HTLs were also fabricated. Compared to the reference device with pure GOs, the short-circuit current (Jsc) was improved from 8.26 to 10.44 mA/cm^2, and FF was enhanced from 64.5% to 66.8%. While open voltage (Voc) remained unchanged, the overall power conversion efficiency (PCE) of the OPVs fabricated with AuNPs/GO was enhanced from 3.26% to 3.98%. We contributed the device enhancement to the effect of localized surface plasmon resonance induced by AuNPs/GO compositions.