Alkyl chain engineering of chlorinated acceptors for elevated solar conversion

Abstract

A chlorinated acceptor with 2-butyloctyl side chains and a 3D interpenetrated structure in the single crystal shows excellent PCE up to 16.43%.

Crystal Engineering in Organic Photovoltaic Acceptors: A 3D Network Approach

“…[ 38 ] The differences of packing structures in the A‐D‐A and A‐DAD‐A type acceptors are noted [ 57 ] and several different intermolecular interactions including Cl∙∙∙S, Cl∙∙∙π, Br∙∙∙S, N∙∙∙F and N∙∙∙S are also described. [ 54–55,57 ] More importantly, the 3D network packing which was first reported by our group [ 37 ] in a Cl‐substituted isomers system. In organic semiconductors, the charge transfer between two adjacent molecules was usually realized by the ππ hopping due to the overlap of π‐orbitals.…”

“…Single crystal X‐ray diffraction techniques were used to determine the packing information at the atomic level to understand the electron transport behaviors and provide an insight into the relationship between structures and properties. [ 59–62 ] In recent years, researchers explored series of single crystal structures used as OSC acceptors, including the perylene diimide‐type, [ 36,38 ] the A‐D‐A‐type, [ 37,39–53 ] the A‐DAD‐A‐type [ 54–57 ] and non‐covalently fused‐ring‐type, [ 41 ] which are summarized in Figure 2 . Wang's group revealed the influence of isomerization on molecular packing arrangements and its photovoltaic performance in the perylene diimide‐type system.…”

“…Similar packing modes have also been observed in chlorinated and brominated acceptors. [ 54,55 ] Specifically, BTIC‐CF 3 ‐γ displays a Y‐type configuration with torsional angles of 3.6° and 5.9° between the cores and end units, and interlocked S∙∙∙OC interactions of 2.67 and 2.73 Å were achieved. It was found the side with closer S∙∙∙OC interaction has better planarity.…”

“…[ 37 ] In this review, we have summarized the chemical structures of FREAs including PDI‐type acceptors, [ 36,38 ] A‐D‐A‐type [ 37,39–53 ] and A‐DAD‐A‐type acceptors. [ 54–57 ] The relationships among molecular design, packing structures and corresponding properties are discussed in details. Ordered J‐aggregate arrangements induced by chlorination are revealed [ 40 ] and the influences of the substituted position and numbers of halogen atoms on the molecular packing are summarized.…”

Boron(iii) β-diketonate-based small molecules for functional non-fullerene polymer solar cells and organic resistive memory devices

“…2f), in which isotropic electron transport could be envisaged. [49][50][51] The single crystal structure of compound 1 and its packing not only suggest the favorable packing motif for the potential application of the BF 2 bdk-based acceptor moiety in constructing A-D-A type NFAs, but also provide for the rst time molecular geometry insights into A-D-A type NFAs with a central tricyclic donor moiety.…”