A5044639247- Organic Electronics and Photovoltaics
- Conducting polymers and applications
- Perovskite Materials and Applications
- Thin-Film Transistor Technologies
- X-ray Diffraction in Crystallography
- Crystallization and Solubility Studies
- Molecular Junctions and Nanostructures
- Organic Light-Emitting Diodes Research
- Crystallography and molecular interactions
- Nanowire Synthesis and Applications
- Semiconductor materials and interfaces
- Force Microscopy Techniques and Applications
- Advanced Battery Technologies Research
- Advancements in Battery Materials
- Fullerene Chemistry and Applications
- Advanced Sensor and Energy Harvesting Materials
- Semiconductor materials and devices
- Advanced Battery Materials and Technologies
- Advanced Memory and Neural Computing
North Carolina State University
2018-2023
Abstract All-polymer solar cells (all-PSCs) based on polymerized small molecular acceptors (PSMAs) have made significant progress recently. Here, we synthesize two A-DA’D-A molecule acceptor PSMAs of PS-Se with benzo[c][1,2,5]thiadiazole A’-core and PN-Se benzotriazole A’-core, for the studies effect structure photovoltaic performance PSMAs. The possess broad absorption showing more red-shifted than suitable electronic energy levels application as polymer in all-PSCs PBDB-T donor. Cryogenic...
Two medium-bandgap p-type organic small molecules H21 and H22 with an alkylsily-thienyl conjugated side chain on benzo[1,2-b:4,5-b']dithiophene central units are synthesized used as donors in all-small-molecule solar cells (SM-OSCs) a narrow-bandgap n-type molecule 2,2'-((2Z,2'Z)-((4,4,9,9-tetrahexyl-4,9-dihydro-s-indaceno[1,2-b:5,6-b']dithiophene-2,7-diyl)bis(methanylylidene))bis(3-oxo-2,3-dihydro-1H-indene-2,1-diylidene))dimalononitrile (IDIC) the acceptor. In comparison to 3-ethyl...
Abstract Tandem organic solar cells are based on the device structure monolithically connecting two to broaden overall absorption spectrum and utilize photon energy more efficiently. Herein, we demonstrate a simple strategy of inserting double bond between central core end groups small molecule acceptor Y6 extend its conjugation length range. As result, new narrow bandgap BTPV-4F was synthesized with an optical 1.21 eV. The single-junction devices as achieved power conversion efficiency over...
Abstract Demonstrated in this work is a simple random ternary copolymerization strategy to synthesize series of polymer acceptors, PTPBT‐ET x , by polymerizing small‐molecule acceptor unit modified from Y6 with thiophene connecting and controlled amount an 3‐ethylesterthiophene (ET) unit. Compared PTPBT only Y6‐like units units, (where represents the molar ratio ET unit) incorporated copolymers show up‐shifted LUMO energy levels, increased electron mobilities, improved blend morphologies...
Abstract Side‐chain modifications of non‐fullerene acceptors (NFAs) are essential for harvesting their full potential in organic solar cells (OSC). Here, an effective alkyl‐chain‐branching approach the Y‐series NFAs flanking meta‐substituted phenyl side groups at outer positions is demonstrated. Compared to BTP‐4F‐PC6 with linear m ‐hexylphenyl chains, two new named BTP‐4F‐P2EH and BTP‐4F‐P3EH developed bulkier alkyl chains branched β γ positions, respectively. These result altered molecular...
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...
Reducing the energy loss of sub-cells is critical for high performance tandem organic solar cells, while it limited by severe non-radiative voltage via formation non-emissive triplet excitons. Herein, we develop an ultra-narrow bandgap acceptor BTPSeV-4F through replacement terminal thiophene selenophene in central fused ring BTPSV-4F, constructing efficient cells. The substitution further decrease optical BTPSV-4F to 1.17 eV and suppress exciton BTPSV-4F-based devices. cells with as...
All-polymer solar cells (all-PSCs) have drawn growing attention and achieved tremendous progress recently, but their power conversion efficiency (PCE) still lags behind small-molecule-acceptor (SMA)-based PSCs due to the relative difficulty on morphology control of polymer photoactive blends. Here, low-cost PTQ10 is introduced as a second donor (a third component) into PM6:PY-IT blend finely tune energy-level matching microscopic layer. The addition decreases π-π stacking distance, increases...
Abstract In the field of non‐fullerene organic solar cells (OSCs), compared to rapid development acceptors, progress high‐performance donor polymers is relatively slow. The property and performance in OSCs are often sensitive molecular weight polymers. this study, a chlorinated polymer named D18‐Cl reported, which can achieve high with wide range weight. devices based on show higher open‐circuit voltage ( V OC ) due slightly deeper energy levels an outstanding short‐circuit current density J...
Abstract Recently, a random ternary copolymerization strategy has become promising and efficient approach to develop high‐performance polymer donors for solar cells (PSCs). In this study, low‐cost electron‐withdrawing unit, 2,5‐bis(4‐(2‐ethylhexyl)thiophen‐2‐yl)pyrazine (PZ‐T), is incorporated into the backbone of PM6 as third component, three D‐A 1 ‐D‐A 2 type terpolymers PMZ‐10, PMZ‐20, PMZ‐30 are synthesized by strategy, with PZ‐T proportion 10%, 20%, 30%, respectively. The exhibit...
Differences in the intermolecular interactions of small molecule acceptors with different chlorine substitution positions affect their molecular packing and photovoltaic properties.
Abstract The effects of central alkoxy side chain length a series narrow bandgap small molecule acceptors (SMAs) on their physicochemical properties and the photovoltaic performance SMA‐based polymer solar cells (PSCs) are systematically investigated. It is found that ordered aggregation these SMAs in films enhanced gradually with increase length. single‐crystal structures further reveal changes can have dramatic impact molecular self‐assembly. short‐circuit current density power conversion...
Abstract To achieve semiconducting materials with high electron mobility in organic field‐effect transistors (OFETs), low‐lying energy levels (the highest occupied molecular orbital (HOMO) and the lowest unoccupied (LUMO)) favorable packing ordering are two crucial factors. Here, it is reported that incorporation of pyridine selenophene into backbone a diketopyrrolopyrrole (DPP)‐based copolymer produces high‐electron‐mobility semiconductor, PDPPy‐Se. Compared analogous polymers based on...
Abstract Discrepancies in reported values of exciton binding energy (E b ) for organic semiconductors (OSs) necessitate a comprehensive study. Traditionally, E is defined as the difference between transport gap t and optical opt ). Here, PBnDT‐TAZ polymer variants are determined using two commonly employed methods: combination ultraviolet photoemission spectroscopy low‐energy inverse (UPS‐LEIPS) solid‐state cyclic voltammetry (CV). obtained by UPS‐LEIPS show low dispersion no clear...
High-performance OSCs were fabricated based on polymer PTQ10 as donor and HO-IDIC-2F acceptor, using non-halogen tetrahydrofuran processing solvent the PCE of as-cast reached 12.20% which is competitive with regular chloroform.
Abstract Compared to conjugated polymers, small‐molecule organic semiconductors present negligible batch‐to‐batch variations, but presently provide comparatively low power conversion efficiencies (PCEs) in small‐molecular solar cells (SM‐OSCs), mainly due suboptimal nanomorphology. Achieving precise control of the nanomorphology remains challenging. Here, two new donors H13 and H14 , created by fluorine chlorine substitution original donor molecule H11 are presented that exhibit a similar or...
Abstract In the field of non‐fullerene organic solar cells (OSCs), most promising polymer donors are based on benzo[1,2‐b:4,5‐b′]dithiophene (BDT) units while benzo[1,2‐b:4,5‐b′]difuran (BDF)‐based polymers have drawn less attention since efficiencies BDF polymer‐based devices generally lower than those BDT ones. this contribution, unit in a donor named D18 is replaced with unit, and new D18‐Fu synthesized. As highly‐crystalline molecule Y6‐1O chosen as acceptor, efficiency binary can reach...
Intra- and intermolecular ordering greatly impact the electronic optoelectronic properties of semiconducting polymers. Despite much prior efforts regarding molecular packing, interrelationship between alkyl sidechains conjugated backbones has not been fully detailed. We report here discovery a highly ordered sidechain phase in six representative polymers, determined from distinct spectroscopic diffraction signatures. The exhibits unusually large coherence lengths at least 70 nm, induces...
Abstract Two n‐type organic semiconductor (n‐OS) small molecules m ‐ITIC‐2F and ‐ITIC‐4F with fluorinated 2‐(2,3‐dihydro‐3‐oxo‐1H‐inden‐1‐ylidene)propanedinitrile (IC) terminal moieties are prepared, for the application as an acceptor in polymer solar cells (PSCs), to further improve photovoltaic performance of n‐OS 3,9‐bis(2‐methylene‐(3‐(1,1‐dicyanomethylene) indanone) ‐5,5,11,11‐tetrakis(3‐hexylphenyl)‐dithieno[2,3‐d:2′,3′‐d′]‐sindaceno[1,2‐b:5,6‐b′]‐dithiophene ( ‐ITIC). Compared ‐ITIC,...
Two polymers J75 and J76 with selenophene instead of thiophene on the conjugated side chain benzodithiophene (BDT) unit or π bridges polymer J71 were designed synthesized, for investigating effect substitution photovoltaic performance donors in comparison J71. The can narrow optical band gap red-shift absorption film by ca. 25 nm, but highest occupied molecular orbital (HOMO) energy level (EHOMO) is up-shifted slightly 0.04 eV. typical electron acceptors fullerene derivative PC71BM...
High-performance low-band-gap polymer semiconductors are visibly colored, making them unsuitable for transparent and imperceptible electronics without reducing film thickness to the nanoscale range. Herein, we demonstrate polymer/insulator blends exhibiting favorable miscibility that improves transparency carrier transport in an organic field-effect transistor (OFET) device. The mesoscale structures leading more efficient charge ultrathin films relevant realization of flexible electronic...