Junwu Chen

Bio: Junwu Chen is an academic researcher from South China University of Technology. The author has contributed to research in topics: Polymer solar cell & Materials science. The author has an hindex of 30, co-authored 112 publications receiving 4044 citations. Previous affiliations of Junwu Chen include Zhejiang University.

Low band-gap conjugated polymers with strong interchain aggregation and very high hole mobility towards highly efficient thick-film polymer solar cells.

Abstract: Absorption spectra of polymer FBT-Th4 (1,4) (M n = 46.4 Kg/mol, E g = 1.62 eV, and HOMO = -5.36 eV) indicate strong interchain aggregation ability. High hole mobilities up to 1.92 cm(2) (V s)(-1) are demonstrated in OFETs fabricated under mild conditions. Inverted solar cells with active layer thicknesses ranging from 100 to 440 nm display PCEs exceeding 6.5%, with the highest efficiency of 7.64% achieved with a 230 nm thick active layer.

All-Polymer Solar Cells Based on a Conjugated Polymer Containing Siloxane-Functionalized Side Chains with Efficiency over 10.

Abstract: A novel wide-bandgap conjugated copolymer based on an imide-functionalized benzotriazole building block containing a siloxane-terminated side-chain is developed. This copolymer is successfully used to fabricate highly efficient all-polymer solar cells (all-PSCs) processed at room temperature with the green-solvent 2-methyl-tetrahydrofuran. When paired with a naphthalene diimide-based polymer electron-acceptor, the all-PSC exhibits a maximum power conversion efficiency (PCE) of 10.1%, which is the highest value so far reported for an all-PSC. Of particular interest is that the PCE remains 9.4% after thermal annealing at 80 °C for 24 h. The resulting high efficiency is attributed to a combination of high and balanced bulky charge carrier mobility, favorable face-on orientation, and high crystallinity. These observations indicate that the resulting copolymer can be a promising candidate toward high-performance all-PSCs for practical applications.

Silole‐Containing Polymers: Chemistry and Optoelectronic Properties

Abstract: In this review, the synthesis and optoelectronic properties of various π-conjugated-, σ-conjugated-, pendanted-, and hyperbranched or dendritic silole-containing polymers (SCPs) are described So far, substituted silole, dibenzosilole, dithienosilole, and bis-silicon-bridged stilbene have been incorporated into SCPs The tunable bandgaps from 40-155 eV, variable fluorescent colors from UV to blue, green, and red (RGB) light, fluorescent chemo-sensors for 2,4,6-trinitrotoluene (TNT)-type explosives, aggregation-induced emission, efficient electroluminescence emissions for RGB lights, phosphorescent hosts with high triplet energy level, efficient solar cells, stable field-effect transistors with high hole mobility in air, and attenuation of strong laser power, are the important features of SCPs

Largely enhanced efficiency with a PFN/Al bilayer cathode in high efficiency bulk heterojunction photovoltaic cells with a low bandgap polycarbazole donor.

Abstract: Polymeric photovoltaic cells (PVCs) have attracted considerable attention over the past several years because of their unique advantages of low cost, light weight, and great potential for the realization of fl exible and large-area devices. [ 1 , 2 ] Typically, bulk heterojunction (BHJ) PVCs, a promising device confi guration for high power conversion effi ciency (PCE), involve the use of a phase-separated blend of an electron-donating conjugated poly mer and an electron-accepting fullerene derivative as the active layer. [ 3 − 10 ] Judicious design of a polymer donor and selection of a fullerene acceptor have realized high effi ciency BHJ PVCs with PCE values over 5%. [ 11 − 16 ] Tremendous efforts have also been made to optimize the active layer formation and the device confi guration. Many optimization methods, such as using different solvents to fabricate the active layer, [ 4 ] thermal annealing of the active layer or the device, [ 17 ] fi lm forming speed, [ 18 ] the addition of additives to the active layer, [ 19 ] the use of an optical spacer, [ 15 ]

Aggregation-Induced Emission: Together We Shine, United We Soar!

Abstract: Ju Mei,†,‡,∥ Nelson L. C. Leung,†,‡,∥ Ryan T. K. Kwok,†,‡ Jacky W. Y. Lam,†,‡ and Ben Zhong Tang*,†,‡,§ †HKUST-Shenzhen Research Institute, Hi-Tech Park, Nanshan, Shenzhen 518057, China ‡Department of Chemistry, HKUST Jockey Club Institute for Advanced Study, Institute of Molecular Functional Materials, Division of Biomedical Engineering, State Key Laboratory of Molecular Neuroscience, Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China Guangdong Innovative Research Team, SCUT-HKUST Joint Research Laboratory, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China

Synthesis of Conjugated Polymers for Organic Solar Cell Applications

Abstract: -phenylenevinylene)s L4. Fluorene-Based Conjugated Polymers L4.1. Fluorene-Based Copolymers ContainingElectron-Rich MoietiesM4.2. Fluorene-Based Copolymers ContainingElectron-Deficient MoietiesN4.3. Fluorene-Based Copolymers ContainingPhosphorescent ComplexesQ5. Carbazole-Based Conjugated Polymers R5.1. Poly(2,7-carbazole)-Based Polymers R5.2. Indolo[3,2-

Enhanced power-conversion efficiency in polymer solar cells using an inverted device structure

Abstract: typically based on n-type metal oxides, our device is solutionprocessed at room temperature, enabling easy processibility over a large area. Accordingly, the approach is fully amenable to highthroughput roll-to-roll manufacturing techniques, may be used to fabricate vacuum-deposition-free PSCs of large area, and find practical applications in future mass production. Moreover, our discovery overturns a well-accepted belief (the inferior performance of inverted PSCs) and clearly shows that the characteristics of high performance, improved stability and ease of use can be integrated into a single device, as long as the devices are optimized, both optically and electrically, by means of a meticulously designed device structure. We also anticipate that our findings will catalyse the development of new device structures and may move the efficiency of devices towards the goal of 10% for various material systems. Previously, we reported that PFN can be incorporated into polymer light-emitting devices (PLEDs) to enhance electron injection from high-work-function metals such as aluminium (work function w of 4.3 eV) 22,23 and has thus been used to realize high-efficiency, air-stable PLEDs 24 . Furthermore, we also found that efficient electron injection can be obtained even in the most noble metals with extremely high work functions, such as gold (w ¼ 5.2 eV), by lowering the effective work function (for example lowering w in gold by 1.0 eV), which has previously been ascribed to the formation of a strong interface dipole 25 .