Bulk heterojunction thin film formation by single and dual feed ultrasonic spray method for application in organic solar cells

Abstract

We here present a way of preparing the polymer: fullerene BHJ using dual feed method which can lead to formation of pure phases. In this report, we present results of our initial experiments in this direction. The effect of process parameters on the thickness and surface roughness of the active layer has been discussed. The structural and optical properties have been studied using the optical microscope, UV—visible spectroscopy and photoluminescence spectroscopy. Significant PL quenching indicates efficient charge separation in the BHJ formed using this technique. We have also compared the BHJ thin films prepared with this dual feed ultrasonic technique with the single feed spray method. The BHJ formed using this technique has been used as an active layer in OSC.

Nonfullerene Ternary Organic Solar Cell with Effective Charge Transfer between Two Acceptors

“…Accordingly, ternary OSCs (TOSCs) have been well developed for overcoming such issues. As an effective electron acceptor, fullerene derivatives, such as [6,6]-phenyl-C 61 /C 71 -butyric acid methyl ester (PC 61 BM/PC 71 BM), have been the most widely used acceptors in OSCs, − but the weak absorption in the visible region and the difficulty in tuning energy levels limit the theoretical performance of the OSCs. Recently, the nonfullerene acceptors have emerged to break this limit.…”