Mingming Chen

Bio: Mingming Chen is an academic researcher from Tianjin University. The author has contributed to research in topics: Carbon & Electrolyte. The author has an hindex of 30, co-authored 88 publications receiving 4889 citations. Previous affiliations of Mingming Chen include Oita University.

MgO-templated mesoporous carbons using a pitch-based thermosetting carbon precursor

Abstract: A pitch-based thermosetting amphiphilic carbonaceous material (CP-A5) was converted to mesoporous carbons (MCs) by an MgO-templated method. The yields of MCs were competitive, up to 17%. Temperature-programmed desorption (TPD), thermogravimetric analysis (TG), high-resolution transmission electron microscopy (HRTEM) and N2 adsorption–desorption were applied to characterize the precursors and MgO-templated MCs. Compared with some published template carbons from thermoplastic materials, less collapse was observed due to the thermosetting property of the carbon precursor. MC73 (MgO/CP-A5 at 7/3 mass ratio) had a surface area of 1991 m2 g−1 and interconnected micropores/mesopores, which endowed it with outstanding electrochemical performance in 1 M TEABF4/PC organic electrolyte, namely, a gravimetric specific capacitance of 90.8 F g−1 at 0.05 A g−1 and a capacitance retention of 91.3% after 10 000 cycles at 1 A g−1. MC73 is a promising electrode material candidate for energy storage by electrical double layer capacitors. Considering their competitive carbon yields as well as the cyclic ability of MgO, development of MCs from coal tar pitch by an MgO-templated method is feasible and promising, particularly in terms of the upgrade of heavy residues in coal-related industry.

Ultrasmall NiS2 Nanocrystals Embedded in Ordered Macroporous Graphenic Carbon Matrix for Efficiently Pseudocapacitive Sodium Storage

Abstract: Abstract Sodium-ion hybrid capacitor (SIHC) is one of the most promising alternatives for large-scale energy storage due to its high energy and power densities, natural abundance, and low cost. However, overcoming the imbalance between slow Na + reaction kinetics of battery-type anodes and rapid ion adsorption/desorption of capacitive cathodes is a significant challenge. Here, we propose the high-rate-performance NiS 2 @OMGC anode material composed of monodispersed NiS 2 nanocrystals (8.8 ± 1.7 nm in size) and N, S-co-doped graphenic carbon (GC). The NiS 2 @OMGC material has a three-dimensionally ordered macroporous (3DOM) morphology, and numerous NiS 2 nanocrystals are uniformly embedded in GC, forming a core–shell structure in the local area. Ultrafine NiS 2 nanocrystals and their nano–microstructure demonstrate high pseudocapacitive Na-storage capability and thus excellent rate performance (355.7 mAh/g at 20.0 A/g). A SIHC device fabricated using NiS 2 @OMGC and commercial activated carbon (AC) cathode exhibits ultrahigh energy densities (197.4 Wh/kg at 398.8 W/kg) and power densities (43.9 kW/kg at 41.3 Wh/kg), together with a long life span. This outcome exemplifies the rational architecture and composition design of this type of anode material. This strategy can be extended to the design and synthesis of a wide range of high-performance electrode materials for energy storage applications.

Graphene and Graphene Oxide: Synthesis, Properties, and Applications

Abstract: There is intense interest in graphene in fields such as physics, chemistry, and materials science, among others. Interest in graphene's exceptional physical properties, chemical tunability, and potential for applications has generated thousands of publications and an accelerating pace of research, making review of such research timely. Here is an overview of the synthesis, properties, and applications of graphene and related materials (primarily, graphite oxide and its colloidal suspensions and materials made from them), from a materials science perspective.

Carbon-based Supercapacitors Produced by Activation of Graphene

Abstract: Supercapacitors, also called ultracapacitors or electrochemical capacitors, store electrical charge on high-surface-area conducting materials. Their widespread use is limited by their low energy storage density and relatively high effective series resistance. Using chemical activation of exfoliated graphite oxide, we synthesized a porous carbon with a Brunauer-Emmett-Teller surface area of up to 3100 square meters per gram, a high electrical conductivity, and a low oxygen and hydrogen content. This sp 2 -bonded carbon has a continuous three-dimensional network of highly curved, atom-thick walls that form primarily 0.6- to 5-nanometer-width pores. Two-electrode supercapacitor cells constructed with this carbon yielded high values of gravimetric capacitance and energy density with organic and ionic liquid electrolytes. The processes used to make this carbon are readily scalable to industrial levels.

Laser Scribing of High-Performance and Flexible Graphene-Based Electrochemical Capacitors

Abstract: Although electrochemical capacitors (ECs), also known as supercapacitors or ultracapacitors, charge and discharge faster than batteries, they are still limited by low energy densities and slow rate capabilities. We used a standard LightScribe DVD optical drive to do the direct laser reduction of graphite oxide films to graphene. The produced films are mechanically robust, show high electrical conductivity (1738 siemens per meter) and specific surface area (1520 square meters per gram), and can thus be used directly as EC electrodes without the need for binders or current collectors, as is the case for conventional ECs. Devices made with these electrodes exhibit ultrahigh energy density values in different electrolytes while maintaining the high power density and excellent cycle stability of ECs. Moreover, these ECs maintain excellent electrochemical attributes under high mechanical stress and thus hold promise for high-power, flexible electronics.

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).