An Organic Dyad Composed of Diathiafulvalene‐Functionalized Diketopyrrolopyrrole–Fullerene for Single‐Component High‐Efficiency Organic Solar Cells

Abstract

Anew low-band gap dyad DPP-Ful, whichconsists of covalently linked dithiafulvalene-functionalized diketopyrrolopyrrole as donor and fullerene (C 60 )a st he acceptor,h as been designed and synthesized.O rganic solar cells were successfully constructed using the DPP-Ful dyad as an active layer.T his system has ar ecord power-conversion efficiency (PCE) of 2.2 %, which is the highest value when compared to reported single-component organic solar cells. Solution-processable organic solar cells (OSC) haveattracted immense attention in both academia and industry owing to their light weight, mechanical flexibility,easy device fabrication, high transparency,and cost-effectiveness over the market-dominant silicon-based solar cells. [1] At present, the state-of-the-art power-conversion efficiency (PCE) of solution-processable OSCs achieved more than 10 %byblending p-conjugated polymers [2] or small-molecule [3] donors with commonly used fullerene acceptors. [4] TheP CE of OSC mainly depends on interpenetrating the nano-sized structured network formed at the interface of the donor and acceptor of the blend film and serves as an efficient charge-transporting carrier. [4a, 5] Then ano-sized structured network of the active layer can be efficiently controlled by tedious optimizing fabrication process by choosing various donor-acceptor ratios and different solvents,solvent/thermal annealing, layer thickness,a nd pinhole-free deposition of the active layer. [1, 6] However,t hese processes severely deteriorate the performance and stability of OSC and retard its commercialization at lower production costs.In an active layer, the aggregate formation of fullerene, which is prone to aggregation, also decreases the donor-

Simply Complex: The Efficient Synthesis of an Intricate Molecular Acceptor for High-Performance Air-Processed and Air-Tested Fullerene-Free Organic Solar Cells

“…Such features may prove favorable for single-component organic solar cells (OSCs). 62 Solution and thin-film UV−vis spectra of PDI-DPP-PDI were obtained from 1.0 w/v% solutions in CHCl 3 (Figure 3a), with solubility measured at >50 mg/mL. The molar absorptivity reaches a high value of 121 300 M −1 cm −1 at λ max (538 nm), which is greater than the individual components DPP (31 700 M −1 cm −1 at 549 nm) and PDI (83 800 M −1 cm −1 at 534 nm).…”

Diketopyrrolopyrrole-Based Conjugated Polymers with Perylene Bisimide Side Chains for Single-Component Organic Solar Cells

“…by developing conjugated block copolymers containing an electron donor and acceptor in one molecule to mimic the BHJ structure, but their performance is far from optimal. [2][3][4][5][6][7] This is mainly because it is difficult to realize the proper nano-phase separation between donor and acceptor in block copolymers, resulting in severe charge (hole and electron) recombination and low photocurrent in solar cells. 8 In contrast, nano-phase separation in BHJ photoactive layers can be intentionally optimized, e.g.…”

Triphenylamine-Based Push–Pull σ–C60 Dyad As Photoactive Molecular Material for Single-Component Organic Solar Cells: Synthesis, Characterizations, and Photophysical Properties

“…63 Since 2016, a dithiafulvalene-functionalized diketopyrrolopyrrole-C 60 dyad and a triad based on an oligothiophene-fullerene conjugate were reported with promising and encouraging PCEs of 2.2% and 2.4%. [64][65] Although the development of SC-OSCs remains very challenging, these last results on small molecules suggest that enhanced PV performance can be obtained by proper design of new D and A components, by playing with the nature of the spacer between D and A, and/or by controlling the self-assembly of resulting discrete molecular assemblies. Chemistry of Materials 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 5…”