Ring Substituents Mediate the Morphology of PBDTTPD-PCBM Bulk-Heterojunction Solar Cells

Abstract

EXPERIMENTAL: Synthetic DetailsMethods and Materials: All reagents from commercial sources were used without further purification.Reactions were carried out under nitrogen atmosphere. Solvents were dried and purified using standard techniques. Flash chromatography was performed with analytical-grade solvents using Silicycle Silica Flash P60 (particle size 40-63 µm, 60 Å, 230 -400 mesh) silica gel. Flexible plates PE SilG/UV 250µm from Whatman ® were used for TLC. Compounds were detected by UV irradiation or staining with I 2 , unless otherwise stated. All compounds were characterized by 1 H NMR (400 MHz) and 13 C NMR ( 100MHz) on a Bruker Avance III Ultrashielded 400 Plus instrument and acquired at room temperature.

Thieno[3,4‐c]Pyrrole‐4,6‐Dione‐Based Polymer Acceptors for High Open‐Circuit Voltage All‐Polymer Solar Cells

“…[36,[43][44] In the design of polymer donors for high-efficiency BHJ solar cells with PCBM acceptors, distinct side chain patterns can induce significant variations in BHJ morphology and intermolecular interactions between donor and acceptor counterparts; [36] turning to polymer acceptors, those effects may also play an important role and influence material performance. Given that both TPD [36][37][38][39][40][41][42][43][44][45][46][47] and 3,4-difluorothiophene ([2F]T) [48][49][54][55] motifs can effectively increase the IP and EA values when involved in polymer main chains, the combination of these two units along the same backbone can be thought of as a relevant design approach to fullerene alternatives. [ [56][57][58][59] The calculations were performed at the tuned ωB97X-D/6-31G(d,p) level of theory, which ensures a robust description of wavefunction localization / delocalization effects along extended -conjugated chains.…”

“…[36][37][38][39][40][41][42] Importantly, in TPD units, various side-chain substituents can be appended at the imide site, providing leverage for solubility when the electron-deficient motif is polymerized with other co-monomers. [36,[43][44] It is worth noting that many of the most useful electron-deficient units used in the design of narrow-gap polymer donors do not usually possess anchoring sites for the substitution of side-chain substituents.…”

Morphological study of polymer/fullerene interfaces via benzene–PCBM interaction

“…The V oc of the PSC devices prepared with DIO-processing delivered similar V oc values for RP1 (0.97 V), RP2 (0.92 V), and RP3 (0.96 V); thus, the identical V oc for all random copolymers were typical features of P(BDTT-TPD)-based copolymer [43]. Table 3 reveals that as the M2:M3 ratio in P1 increased (10:90, 20:90, and 30:70) to obtain RP1-RP3, the PCEs of the inverted devices (prepared with 3 v% DIO processing) based on RP1-RP3 increased from 3.0% to 4.9%.…”

8.0% Efficient All‐Polymer Solar Cells with High Photovoltage of 1.1 V and Internal Quantum Efficiency near Unity

“…The performance of PBDT-TPD:PC 71 BM solar cells is in reasonable agreement with the previous reports. [38,39,[45][46][47] The conventional and inverted all-PSCs based on PBDT-TPD:PNDI-T afford almost the same performance with V oc of 1.10 V and PCEs of 7.3%. On the other hand, the conventional PBDTS-TPD:PNDI-T all-PSC attains a higher PCE of 8.0%.…”