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Two donor-acceptor alternating copolymers based on electron-rich triarylamine, di(1-(6-(2-ethylhexyl))naphthyl)phenylamine ( DNPA ), and electron-deficient benzothiadiazole and benzoselenadiazole derivatives were designed and synthesized via Suzuki coupling reaction. The resulting triarylamine-based alternating copolymers PDNPADTBT and PDNPADTBS showed good solubility in common organic solvents and good thermal stability. The optical band gaps determined from the onset absorption were 1.93 and 1.81 eV, respectively. By introducing the naphthalene ring into the triarylamine, copolymers had relatively deep HOMO energy levels of −5.48 and −5.45 eV, which led to a high open circuit voltage ( V oc ) and good air stability for photovoltaic application. Bulk heterojunction solar cells were fabricated with a structure of ITO/PEDOT-PSS/copolymers-PC 70 BM/LiF/Al by blending the copolymer with PC 70 BM. Both blend systems showed remarkably high V oc near 0.9 V, and the highest performance of 2.2% was obtained from PDNPADTBT , with V oc = 0.88 V, J sc = 7.4 mA/cm 2 , and a fill factor of 34.4% under AM 1.5 G. [ABSTRACT FROM AUTHOR]

We attempted to manufacture films in which fluorescent dye is dispersed using engineering plastic as a matrix which has high heat and chemical resistance as well as excellent mechanical performance. In this study, films containing highly dispersed perylene in colorless and transparent aromatic polyamide (PA) and polyimide (PI) were manufactured. The perylene-dispersed PA film emitted strong blue light with a maximum fluorescence at 457 nm. On the other hand, the perylene-dispersed PI film showed significant fluorescence quenching with its maximum fluorescence wavelength significantly red-shifted to 546 nm. The perylene-dispersed PI film treated with ethylene diamine at 80 °C showed strong blue fluorescence, and when the film was further heated at 200 °C, the fluorescence was quenched. These films are expected to be applied as back light unit or color conversion layer for OLED and Micro LED due to their excellent physical properties. [Display omitted] • Aromatic polyamide and polyimide films in which perylene was dispersed were prepared. • The polyamide film emitted strong blue light. • The polyimide film showed significantly quenched orange fluorescence. • When treated with ethylene diamine, the polyimide film emitted strong blue light. • When heated at a higher temperature, the fluorescence was quenched again. [ABSTRACT FROM AUTHOR]

Two donor–acceptor conjugated copolymers comprised of a novel dithienophosphole (DTP) as the acceptor unit and bithiophene (BT) or decylthiophenebenzodithiophene (DTBDT) as the donor unit were synthesized and characterized to elucidate the relationship between donor–acceptor (D–A) architecture and organic field-effect transistors (OFETs) performance. These characteristics of D–A copolymers were affected by the structural suitability of donor and acceptor units. Poly(DTP-BT) had an ordered structure that facilitated charge carrier transfer. The crystallinity of poly(DTP-BT) increased as annealing temperature ( T ann ) increased. In contrast, poly(DTP-DTBDT) was amorphous regardless of T ann due to the long alkyl chains of the DTBDT units. OFET devices made with poly(DTP-BT) and annealed at 200 °C exhibit a highly crystalline morphology and a relatively high field-effect mobility (4.9 × 10 −3 cm 2 /(V·s)). [ABSTRACT FROM AUTHOR]

We propose the monolithic structure with series-connected perovskite solar cell and an all-solid-state supercapacitor. So far, impedance behavior for any solar cell integrated with SC has not been reported and we validate the interfacial behavior of 4-PCSD for the first time. As a result, we reveal PSC serves as a stable power source for SC by the impedance behavior. The characteristics of 4-PCSD, such as compact structure, indoor charging, and stable life-time under ambient conditions underline the high potential of 4-PCSD as portable small power source. [Display omitted] • Integrated solar cell and supercapacitor operating at 3 V is proposed. • Impedance spectroscopy analyzed to identify the interfacial behaviors of PCSD. • PCSD exhibited overall efficiency of 13.17 % at 1 mA cm−2 and 9.87 % at 20 mA cm−2. • The 4-PCSD showed remarkable cycle performance under indoor light illumination. • Encapsulated 4-PCSD was operated at 3 V for 8 weeks. The integration of an energy harvesting device and an energy storage device into one unit has been widely studied as a distributed power source. Herein, we propose a high-voltage-driven photo-charging storage device, integrating a series-connected perovskite solar cell and an ionogel-based solid supercapacitor. The photo-charging storage device exhibits high overall efficiencies of 13.17 % and 9.87 % at 1 mA cm−2 and 20 mA cm−2, respectively, attributed to its high storage efficiency of over ∼ 70 % at all discharge current densities. This high discharge current density of 20 mA cm−2 is the record value for all reported integrated solar cells and electric double-layer capacitor systems. Moreover, the photo-charging storage device maintains 78.6 % of its overall efficiency after 100 cycles under AM 1.5 G illumination and exhibits remarkable cycle performance under indoor light illumination. To understand the interfacial behavior of the photo-charging storage device, impedance spectroscopy is performed for the first time. In addition, to avoid the decomposition of the perovskite solar cell active layer with moisture, an encapsulation process is conducted, which enables the device to remain operational at 3 V after 8 weeks. These results underline the high potential of this photo-charging storage device as a portable power source. [ABSTRACT FROM AUTHOR]

We investigated the effects of the solvent boiling point on organic field-effect transistor (OFET) device performances in devices prepared using two newly synthesized anthradithiophene derivatives: 9,10-di(4′-pentylphenylethynyl)-anthra[2,3-b:6,7-b′]dithiophene (DPPEADT) and 9,10-bi([9′,9′-dimethyl-fluoren-2-ylethynyl])-anthra[2,3-b:6,7-b′]dithiophene (DFEADT). DPPEADT exhibited a distinct crystalline morphology whereas DFEADT was amorphous. We characterized the relationship between the molecular structures, film morphologies, and OFET device performances in devices prepared using solvents having one of three different boiling points (chlorobenzene, 1,2-dichlorobenzene, and 1,2,4-trichlorobenzene). 1,2,4-Trichlorobenzene, which provided the highest boiling point among the solvents tested and acted as a good solvent for DPPEADT, significantly improved the field-effect mobilities of DPPEADT devices up to 0.16 cm 2 /V by enhancing the crystallinity of the film. OFETs based on amorphous DFEADT films prepared using the three solvents did not provide enhanced electrical performances. The differences between the transistor performances were attributed to the degree of π-overlap, the molecular structures, and the morphological properties of the films. [ABSTRACT FROM AUTHOR]

Highlights: [•] New copolymers based dialkylterthiophene. [•] Among copolymers, PBTOT had relatively good solubility and crystalline structure. [•] PBTOT showed field effect mobility of 1.73×10−2 cm2 V−1 S−1. [•] PBTOT showed power conversion efficiency of 3.2%. [ABSTRACT FROM AUTHOR]

Abstract: The synthesis and characterization of cyclohexylethenyl end-capped quaterthiophenes is reported. Additionally, an investigation of the performance of organic field-effect transistors based on these quaterthiophenes in view of the relationship between the solid-state (or aggregate) order and the electronic performance is described. UV–vis absorption measurements revealed that the quaterthiophene with an asymmetrically substituted cyclohexylethynyl end-group induced the formation of H-type aggregates, whereas the quaterthiophene with a symmetrically substituted cyclohexylethynyl end-groups favored the formation of J-type aggregates. Two-dimensional grazing-incidence wide-angle X-ray scattering studies were performed to support the molecular structure-dependent packing of films of the new quaterthiophenes. Solution-processed quaterthiophenes were tested as the active layers of p-type organic field-effect transistors with a bottom gate/top contact geometry. The field-effect mobility of devices that incorporated asymmetric quaterthiophene molecules was quite high, exceeding 0.02 cm2/V s, due to H-aggregation and good in-plane ordering. In contrast, the field-effect mobility of devices that incorporated symmetrical quaterthiophenes, was low, above 5 × 10−4 cm2/(V s), due to the formation of J-aggregates and poor in-plane ordering. A comparison of the symmetrical and asymmetrical quaterthiophene derivatives revealed that the molecular aggregation-dependent packing, determined by the cyclohexylethynyl end groups, was responsible for influencing the organic field-effect transistor performance. [Copyright &y& Elsevier]

Abstract: We investigated thin films comprised of a blend of poly(5,5′-bis(3-dodecylthiophene-2-yl)2–2′-biselenophene)/[6,6] and phenyl C61 butyric acid methyl ester (PDT2Se2/PCBM) for use in bulk heterojunction photovoltaic cells. The charge transport characteristics of PDT2Se2 and its analog, poly(3,3′′′-didodecyl quaterthiophene) (PQT-12), were elucidated through analysis of the space charge limited current behavior at various temperatures. PDT2Se2 showed higher mobilities, lower field activation parameters, and a lower temperature dependence of these parameters than did PQT-12, indicating better charge transport in PDT2Se2. Optimization of the PDT2Se2:PCBM composition ratio produced a bicontinuous donor–acceptor network with domain sizes on the order of 10nm, which afforded power conversion efficiencies of 1.4%, a short circuit current density of 4.3mAcm−2, an open circuit voltage of 0.69V, and a fill factor of 47%. This performance was much better than the performance achieved previously using PQT-12:PCBM blend systems. Selenophene substitution appears to be an effective strategy for enhancing the photovoltaic effect of thiophene-based polymeric semiconductors for high performance organic solar cells (OSCs). [Copyright &y& Elsevier]