Renewed Prospects for Organic Photovoltaics

Chemical Reviews, Journal Year: 2022, Volume and Issue: 122(18), P. 14180 - 14274

Published: Aug. 5, 2022

Organic photovoltaics (OPVs) have progressed steadily through three stages of photoactive materials development: (i) use poly(3-hexylthiophene) and fullerene-based acceptors (FAs) for optimizing bulk heterojunctions; (ii) development new donors to better match with FAs; (iii) non-fullerene (NFAs). The application NFAs an A–D–A configuration (where A = acceptor D donor) has enabled devices efficient charge generation small energy losses (Eloss < 0.6 eV), resulting in substantially higher power conversion efficiencies (PCEs) than FA-based devices. discovery Y6-type (Y6 2,2′-((2Z,2′Z)-((12,13-bis(2-ethylhexyl)-3,9-diundecyl-12,13-dihydro-[1,2,5]-thiadiazolo[3,4-e]-thieno[2″,3″:4′,5′]thieno-[2′,3′:4,5]pyrrolo-[3,2-g]thieno-[2′,3′:4,5]thieno-[3,2-b]indole-2,10-diyl)bis(methanylylidene))bis(5,6-difluoro-3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile) A–DA′ D–A further propelled the PCEs go beyond 15% due smaller Eloss values (∼0.5 eV) external quantum efficiencies. Subsequently, Y6-series single-junction increased >19% may soon approach 20%. This review provides update recent progress OPV following aspects: developments novel donors, understanding structure–property relationships underlying mechanisms state-of-the-art OPVs, tasks underpinning commercialization such as device stability, module development, potential applications, high-throughput manufacturing. Finally, outlook prospects section summarizes remaining challenges technology.

Language: Английский

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Fine-tuning of side-chain orientations on nonfullerene acceptors enables organic solar cells with 17.7% efficiency

Energy & Environmental Science, Journal Year: 2021, Volume and Issue: 14(6), P. 3469 - 3479

Published: Jan. 1, 2021

Regulating side-chain orientations of Y-series NFAs is a promising strategy to achieve favorable morphology, and high charge mobility solar cell performances, which enables high-performance devices with efficiency approaching 18%.

Language: Английский

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Regio‐Regular Polymer Acceptors Enabled by Determined Fluorination on End Groups for All‐Polymer Solar Cells with 15.2 % Efficiency

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(18), P. 10137 - 10146

Published: Jan. 27, 2021

Abstract Polymerization sites of small molecule acceptors (SMAs) play vital roles in determining device performance all‐polymer solar cells (all‐PSCs). Different from our recent work about fluoro‐ and bromo‐ co‐modified end group IC‐FBr (a mixture IC‐FBr1 IC‐FBr2), this paper, we synthesized purified two regiospecific substituted groups (IC‐FBr‐ o & IC‐FBr‐ m ), which were then employed to construct regio‐regular polymer named PYF‐T‐ , respectively . In comparison with its isomeric counterparts different conjugated coupling sites, exhibits stronger bathochromic absorption achieve better photon harvesting. Meanwhile, adopts more ordered inter‐chain packing suitable phase separation after blending the donor PM6, resulted suppressed charge recombination efficient transport. Strikingly, observed a dramatic difference between While devices based on PM6:PYF‐T‐ can yield power conversion efficiency (PCE) 15.2 %, only show poor efficiencies 1.4 %. This demonstrates success configuration‐unique fluorinated designing high‐performance regular acceptors, provides guidelines towards developing all‐PSCs efficiencies.

Language: Английский

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A Synergistic Strategy of Manipulating the Number of Selenophene Units and Dissymmetric Central Core of Small Molecular Acceptors Enables Polymer Solar Cells with 17.5 % Efficiency

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 60(35), P. 19241 - 19252

Published: June 3, 2021

Abstract A dissymmetric backbone and selenophene substitution on the central core was used for synthesis of symmetric or A‐DA′D‐A type non‐fullerene small molecular acceptors (NF‐SMAs) with different numbers selenophene. From S‐YSS‐Cl to A‐WSSe‐Cl S‐WSeSe‐Cl , a gradually red‐shifted absorption larger electron mobility crystallinity in neat thin film observed. exhibit stronger tighter intermolecular π–π stacking interactions, extra S⋅⋅⋅N non‐covalent interactions from benzothiadiazole, better ordered 3D interpenetrating charge‐transfer networks comparison thiophene‐based . The ‐based device has PCE 17.51 %, which is highest value selenophene‐based NF‐SMAs binary polymer solar cells. combination precise replacement effective improve J sc FF without sacrificing V oc

Language: Английский

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Design of Near‐Infrared Nonfullerene Acceptor with Ultralow Nonradiative Voltage Loss for High‐Performance Semitransparent Ternary Organic Solar Cells

Angewandte Chemie International Edition, Journal Year: 2021, Volume and Issue: 61(19)

Published: Dec. 28, 2021

Semitransparent organic solar cells (ST-OSCs) are considered as one of the most valuable applications OSCs and a strong contender in market. However, optical band gap current high-performance ST-OSCs is still not low enough to achieve optimal balance between power conversion efficiency (PCE) average visible transmittance (AVT). An N-substituted asymmetric nonfullerene acceptor SN with over 40 nm bathochromically shifted absorption compared Y6 was designed synthesized, based on which device PM6 donor obtained PCE 14.3 %, accompanied nonradiative voltage loss 0.15 eV. Meanwhile, ternary devices addition into : can 17.5 % an unchanged open-circuit improved short-circuit current. Benefiting from extended NIR lowered loss, were fabricated optimized demonstrated 14.0 at AVT 20.2 highest 20 %.

Language: Английский

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A highly crystalline non-fullerene acceptor enabling efficient indoor organic photovoltaics with high EQE and fill factor

Joule, Journal Year: 2021, Volume and Issue: 5(5), P. 1231 - 1245

Published: April 28, 2021

Language: Английский

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Selenium-Containing Organic Photovoltaic Materials

Accounts of Chemical Research, Journal Year: 2021, Volume and Issue: 54(20), P. 3906 - 3916

Published: Oct. 4, 2021

ConspectusOrganic photovoltaics (OPVs) with a photoactive layer containing blend of organic donor and acceptor species are considered to be promising technology for clean energy owing their unique flexible form factor good solution processability that can potentially address the scalability challenges. The delicate designs both donors acceptors have significantly enhanced power conversion efficiency OPVs more than 18%. Nonfullerene small-molecule (NFAs) played critical role in enhancing short-circuit current density (JSC) by efficiently harvesting near-infrared (NIR) sunlight. To take full advantage abundant NIR photons, optical band gap NFAs should further reduced improve performance OPVs. Incorporating highly polarizable selenium atoms onto backbone conjugated materials has been proven an effective way decrease gap. For example, selenium-substituted NFA recently developed our group attained JSC approximate 27.5 mA cm-2 OPV devices, surpassing those most emerging photovoltaic systems. Inspired this advance, we concentrate on topic selenium-containing Account incite readers' interest exploring series materials.In Account, first compare differences among chalcogen heterocycles discuss influence fundamental electronic behavior collective photoelectrical properties resulting materials. superior features summarized as follows: (1) large covalent radius diminish π-orbital overlap, rendering quinoidal resonance character narrowed (2) atom is sulfur its larger looser outermost electron cloud, enabling intermolecular Se-Se interaction increased charge carrier mobility relevant solid state. We then focus summarizing design rules various categories including polymer donors, acceptors, especially composed ladder-type polycyclic units. motivation incorporating into these structure-property relationships were thoroughly elucidated. Specifically, changes gap, mobility, molecular packing induced substitution correlate effects exciton behaviors, loss, nanoscale film morphology corresponding devices. Furthermore, point out intrinsic stability under maximum-power-point tracking long-term photo- or thermostress indicate potential use semitransparent tandem solar cells. At end, prospect future research focuses possible applications field discussed.

Language: Английский

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From Solution to Thin Film: Molecular Assembly of π-Conjugated Systems and Impact on (Opto)electronic Properties

Chemical Reviews, Journal Year: 2023, Volume and Issue: 123(13), P. 8395 - 8487

Published: June 5, 2023

The assembly of conjugated organic molecules from solution to solid-state plays a critical role in determining the thin film morphology and optoelectronic properties solution-processed electronics photovoltaics. During evaporative processing, π-conjugated systems can assemble via various forms intermolecular interactions, forming distinct aggregate structures that drastically tune charge transport landscape solid-state. In blend composed donor polymer acceptor molecules, neat materials couples with phase separation crystallization processes, leading complex transition pathways which govern morphology. this review, we provide an in-depth review molecular processes polymers nonfullerene small molecule acceptors discuss their impact on properties. We then shift our focus relevant solar cells fundamentals highlight how processing conditions affect device performance.

Language: Английский

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Improved photovoltaic performance and robustness of all-polymer solar cells enabled by a polyfullerene guest acceptor

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: April 22, 2023

Abstract Fullerene acceptors typically possess excellent electron-transporting properties and can work as guest components in ternary organic solar cells to enhance the charge extraction efficiencies. However, conventional fullerene small molecules suffer from undesirable segregation dimerization, thus limiting their applications cells. Herein we report use of a poly(fullerene- alt -xylene) acceptor (PFBO-C12) component enables significant efficiency increase 16.9% for binary 18.0% all-polymer Ultrafast optic optoelectronic studies unveil that PFBO-C12 facilitate hole transfer suppress recombination. Morphological investigations show blends maintain favorable morphology with high crystallinity smaller domain size. Meanwhile, introduction reduces voltage loss light stability mechanical durability flexible devices. This demonstrates introducing polyfullerenes is an effective approach achieving highly efficient good robustness.

Language: Английский

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A Difluoro‐Monobromo End Group Enables High‐Performance Polymer Acceptor and Efficient All‐Polymer Solar Cells Processable with Green Solvent under Ambient Condition

Advanced Functional Materials, Journal Year: 2021, Volume and Issue: 31(25)

Published: May 2, 2021

Abstract In this paper, a difluoro‐monobromo end group is designed and synthesized, which then used to construct novel polymer acceptor (named PY2F‐T) yielding high‐performance all‐polymer solar cells with 15.22% efficiency. The fluorination strategy can increase the intramolecular charge transfer interchain packing of previous PY‐T based acceptor, significantly improve photon harvesting mobility resulting acceptor. addition, detailed morphology investigations reveal that PY2F‐T‐based blend shows smaller domain spacing higher purity, suppress recombination as supported by time‐resolved techniques. These properties enable simultaneously enhanced J SC FF devices, eventually delivering device efficiencies over 15%, outperforming devices on non‐fluorinated (13%). More importantly, active layers be processed under ambient conditions still achieve 14.37% They also using non‐halogenated solvent o ‐xylene (no additive) yield decent performance 13.05%. This work demonstrates success in design acceptors, provide guidelines for developing new all‐PSCs better stabilities commercial applications.

Language: Английский

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