Guankui Long

Bio: Guankui Long is an academic researcher from Nankai University. The author has contributed to research in topics: Organic solar cell & Polymer solar cell. The author has an hindex of 39, co-authored 99 publications receiving 10365 citations. Previous affiliations of Guankui Long include Nanyang Technological University & University of Toronto.

A series of simple oligomer-like small molecules based on oligothiophenes for solution-processed solar cells with high efficiency.

Abstract: A series of acceptor-donor-acceptor simple oligomer-like small molecules based on oligothiophenes, namely, DRCN4T-DRCN9T, were designed and synthesized. Their optical, electrical, and thermal properties and photovoltaic performances were systematically investigated. Except for DRCN4T, excellent performances were obtained for DRCN5T-DRCN9T. The devices based on DRCN5T, DRCN7T, and DRCN9T with axisymmetric chemical structures exhibit much higher short-circuit current densities than those based on DRCN6T and DRCN8T with centrosymmetric chemical structures, which is attributed to their well-developed fibrillar network with a feature size less than 20 nm. The devices based on DRCN5T/PC71BM showed a notable certified power conversion efficiency (PCE) of 10.10% under AM 1.5G irradiation (100 mW cm(-2)) using a simple solution spin-coating fabrication process. This is the highest PCE for single-junction small-molecule-based organic photovoltaics (OPVs) reported to date. DRCN5T is a rather simpler molecule compared with all of the other high-performance molecules in OPVs to date, and this might highlight its advantage in the future possible commercialization of OPVs. These results demonstrate that a fine and balanced modification/design of chemical structure can make significant performance differences and that the performance of solution-processed small-molecule-based solar cells can be comparable to or even surpass that of their polymer counterparts.

Small-molecule solar cells with efficiency over 9%

Abstract: Solution-processed small-molecule solar cells with almost 100% internal quantum efficiency and a power conversion efficiency of 9% are reported. The cells make use of a donor molecule called DRCN7T and use PC71BM as an acceptor.

Solution-processed and high-performance organic solar cells using small molecules with a benzodithiophene unit.

Abstract: Three small molecules named DR3TBDTT, DR3TBDTT-HD, and DR3TBD2T with a benzo[1,2-b:4,5-b']dithiophene (BDT) unit as the central building block have been designed and synthesized for solution-processed bulk-heterojunction solar cells. Power conversion efficiencies (PCEs) of 8.12% (certified 7.61%) and 8.02% under AM 1.5G irradiation (100 mW cm(-2)) have been achieved for DR3TBDTT- and DR3TBDT2T-based organic photovoltaic devices (OPVs) with PC71BM as the acceptor, respectively. The better PCEs were achieved by improving the short-circuit current density without sacrificing the high open-circuit voltage and fill factor through the strategy of incorporating the advantages of both conventional small molecules and polymers for OPVs.

Solution-Processed Organic Solar Cells Based on Dialkylthiol-Substituted Benzodithiophene Unit with Efficiency near 10%

Abstract: A small molecule named DR3TSBDT with dialkylthiol-substituted benzo[1,2-b:4,5-b′]dithiophene (BDT) as the central unit was designed and synthesized for solution-processed bulk-heterojunction solar cells. A notable power conversion efficiency of 9.95% (certified 9.938%) has been achieved under AM 1.5G irradiation (100 mW cm–2), with an average PCE of 9.60% based on 50 devices.

Porous 3D graphene-based bulk materials with exceptional high surface area and excellent conductivity for supercapacitors.

Abstract: Until now, few sp2 carbon materials simultaneously exhibit superior performance for specific surface area (SSA) and electrical conductivity at bulk state. Thus, it is extremely important to make such materials at bulk scale with those two outstanding properties combined together. Here, we present a simple and green but very efficient approach using two standard and simple industry steps to make such three-dimensional graphene-based porous materials at the bulk scale, with ultrahigh SSA (3523 m2/g) and excellent bulk conductivity. We conclude that these materials consist of mainly defected/wrinkled single layer graphene sheets in the dimensional size of a few nanometers, with at least some covalent bond between each other. The outstanding properties of these materials are demonstrated by their superior supercapacitor performance in ionic liquid with specific capacitance and energy density of 231 F/g and 98 Wh/kg, respectively, so far the best reported capacitance performance for all bulk carbon materials.

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

Polymer solar cells

Abstract: This Review summarizes recent progress in the development of polymer solar cells. It covers the scientific origins and basic properties of polymer solar cell technology, material requirements and device operation mechanisms, while also providing a synopsis of major achievements in the field over the past few years. Potential future developments and the applications of this technology are also briefly discussed.

Recent Advances in Ultrathin Two-Dimensional Nanomaterials

Abstract: Since the discovery of mechanically exfoliated graphene in 2004, research on ultrathin two-dimensional (2D) nanomaterials has grown exponentially in the fields of condensed matter physics, material science, chemistry, and nanotechnology. Highlighting their compelling physical, chemical, electronic, and optical properties, as well as their various potential applications, in this Review, we summarize the state-of-art progress on the ultrathin 2D nanomaterials with a particular emphasis on their recent advances. First, we introduce the unique advances on ultrathin 2D nanomaterials, followed by the description of their composition and crystal structures. The assortments of their synthetic methods are then summarized, including insights on their advantages and limitations, alongside some recommendations on suitable characterization techniques. We also discuss in detail the utilization of these ultrathin 2D nanomaterials for wide ranges of potential applications among the electronics/optoelectronics, electrocat...

Graphene-based composites

Abstract: Graphene has attracted tremendous research interest in recent years, owing to its exceptional properties. The scaled-up and reliable production of graphene derivatives, such as graphene oxide (GO) and reduced graphene oxide (rGO), offers a wide range of possibilities to synthesize graphene-based functional materials for various applications. This critical review presents and discusses the current development of graphene-based composites. After introduction of the synthesis methods for graphene and its derivatives as well as their properties, we focus on the description of various methods to synthesize graphene-based composites, especially those with functional polymers and inorganic nanostructures. Particular emphasis is placed on strategies for the optimization of composite properties. Lastly, the advantages of graphene-based composites in applications such as the Li-ion batteries, supercapacitors, fuel cells, photovoltaic devices, photocatalysis, as well as Raman enhancement are described (279 references).