4th. International Marmara Sciences Congress, IMASCON 2020 Spring, Kocaeli, Turkey, 19 - 20 June 2020, pp.1
The organic photovoltaics solar cells have attracted a lot of attention over the last few decades. Comparing with conventional photovoltaic materials, polymer based organic solar cells offer many practical advantages due to low-cost and easy fabrication techniques, and potential to deposit on flexible materials. Additionally, organic polymer materials also have relatively high absorption coefficients (~4x105 cm-1) in the visible range of electromagnetic spectrum. A typical conductive polymer based solar cell has a sandwiched structure with anode, photoactive material, and cathode. In order to improve device performances, it is often to introduce interfacial layers between the anode and cathode interfaces. These interfacial layers can be conductive polymers, nano-structure materials or metal oxides. In addition to these properties, the organic solar cells are the potential to double the efficiency by using the tandem structure.
In this study, the blended of poly(3-hexylthiophene-2,5-diyl) (P3HT) and [6,6]-phenyl C61-butyric acid methyl ester (PCBM) bulk heterojunction (BHJ) photoactive layer has been used to produce inverted polymer solar cells (IPSC). In order to deposit metal oxide layers, two different methods were used, RF magnetron sputtering and spin-coating methods. Metal oxide of TiO2, SnO2 and ZnO were coated on well cleaned ITO and FTO. Spin-coater method was used to produce the P3HT:PCBM organic photoactive thin film layer on the metal oxide layers. The hole-collecting layer of molybdenum trioxide (MoO3) and the top metal electrode of silver (Ag) layers were deposited on the Glass/FTO or ITO/Metal oxide/P3HT:PCBM by using thermal evaporation method. The surface morphology, structural and optical properties of TiO2, SnO2 and ZnO electron selective layers were studied by performing X-ray diffraction (XRD), confocal Raman spectroscopy, transmittance spectra and Atomic Force Microscope (AFM). Produced IPSC devices with TiO2 SnO2 and ZnO thin films indicated the best device performance with PCE values in between 1.62 and 3.91%.