Fotovoltaik Hücrelerin Yüzey Morfolojisi ve Verimliliği Üzerinde Termal Tavlama Etkisi

Year 2023, Volume: 26 Issue: 1, 125 - 129, 27.03.2023

Kevser Şahin Tıraş , Thilini Rupasinghe Markus Wohlgenannt , Alexei Tivanski

https://doi.org/10.2339/politeknik.942188

Abstract

Fotovoltaikler, güneş ışığını elektrik akımına dönüştürür. Bu çalışmada silikon ile yapılan malzemeler yerine elektron verici ve alıcı içeren karışımlar kullanılmıştır. Karbon bazlı organik yarı iletkenlerin işlenmesi kolaydır ve üretim maliyetleri düşüktür. Fotovoltaik cihaz performansında, substrat hazırlama, karışımdaki polimer-alıcı oranları, aktif katmanın termal tavlanması ve üst elektrot biriktirme gibi önemli rol oynayan birkaç üretim adımı vardır. Karışımın nano ölçekli morfolojisinin termal tavlama işlemi ile değiştirilebileceği gösterilmiştir. Sonuç olarak, verim yüzey pürüzlülüğünden etkilenir. İnce filmler ve fotovoltaik hücreler üretmek için donör: alıcı olarak P3HT: PCBM karışımı kullanıldı. Çeşitli zamanlarda tavlanan cihazların güç dönüşüm verimleri ve yüzey morfolojileri ölçülmüştür. Atomik kuvvet mikroskobu (AFM) görüntüleri, aktif tabakanın yüzey pürüzlülüğünün esas olarak tavlama süresinden etkilendiğini ve en pürüzlü yüzeye sahip filmin en verimli güneş pili ile sonuçlandığını ortaya çıkardı.

Keywords

AFM, polimerler, fotovoltaikler, termal tavlama

Thermal Annealing Effect on the Surface Morphology and Efficiency of Photovoltaic Cells

Abstract

Photovoltaics convert solar radiation into electrical current. For the present study, blends containing electron donor and acceptor are used instead of materials made with silicon. Carbon-based organic semiconductors are easy to process and have low fabrication costs. There are several fabrication steps playing important role in the photovoltaic device performance such as, substrate preparation, polymer-acceptor ratios in the blend, thermal annealing of the active layer and top electrode deposition. It has been shown that nanoscale morphology of the blend can be altered via thermal annealing treatment. As a result, efficiency is affected by surface roughness. The blend of P3HT: PCBM as donor: acceptor was used to fabricate thin films and photovoltaic cells. The power conversion efficiencies and surface morphologies of the devices annealed at various times were measured. Atomic force microscopy (AFM) images revealed that the surface roughness of the active layer is mainly affected by the annealing time, and the film with the roughest surface results in the most efficient solar cell.

Keywords

Atomic force microscopy, polymers, photovoltaics, thermal annealing

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