Non-halogenated and non-volatile solid additive for improving the efficiency and stability of organic solar cells

Abstract

A non-halogenated and non-volatile solid additive PID can interact simultaneously with donor and acceptor molecules and stabilize the bulk-heterojunction morphology, increasing the efficiency and thermal stability of organic solar cell devices.

Unveiling the significance of adduct formation between thiocarbonyl Lewis donors and diiodine for the structural organization of rhodanine-based small molecule semiconductors

“…The second category, solid additives, operates distinctively from their solvent counterparts, first because they alter the intermolecular interaction among π-conjugated compounds, and second because they are incorporated into the films, so in principle they do not require high temperature for their removal. 26–28 Such a scenario is particularly interesting as it avoids the risk of film degradation which inevitably leads to a reduction in device performance. Examples of solid additives include 7-dibromo-9,9-dimethyl fluorene (DBDMF), hydroxy-methylpyrimidine derivatives, 9-fluorenone-1-carboxylic acid (FCA), 2-benzylidene-1-indene-1,3-dione and its derivatives, and diiodine.…”

“…Examples of solid additives include 7-dibromo-9,9-dimethyl fluorene (DBDMF), hydroxy-methylpyrimidine derivatives, 9-fluorenone-1-carboxylic acid (FCA), 2-benzylidene-1-indene-1,3-dione and its derivatives, and diiodine. 26–30 The latter additive is particularly intriguing because it is commonly employed also as a p-type chemical dopant for both small molecules and π-conjugated polymers, contributing to the enhancement of charge carriers in the semiconductor layer. 29,30 However, the optimal generation of charge carriers relies heavily on the homogeneous distribution of the dopant throughout the material.…”