Carbon Materials For Energy Storage Research Articles

Facile synthesis of wheat bran-derived honeycomb-like hierarchical carbon for advanced symmetric supercapacitor applications

A novel honeycomb-like hierarchical carbon (HHC) derived from wheat bran has been obtained by the facile and environmentally friendly method via hydrothermal carbonization of wheat bran followed by KOH activation process at mild conditions without any template. The prepared carbon has a large Brunauer–Emmett–Teller (BET) surface area of 2,189.2 m2 g−1 and pore volumes of up to 1.1 cm3 g−1. The performance of the HHC as electrodes for electrochemical supercapacitors was evaluated in a symmetric two-electrode cell configuration with 6 M KOH and 1 M TEABF4/AN as the electrolytes. Electrochemical studies show that the supercapacitors based on the as-prepared HHC exhibit an excellent capacitive performance in both aqueous and organic electrolytes. We attribute the outstanding capacitive behavior of HHC to their unique structure and high accessible surface area. Considering that the cost-effective and feasible process, this facile technique presented here will not only provide a promising method for the production of biomass-derived hierarchical carbon but also put forward the application of carbon materials in energy storage and conversion.

La2O3 Doped Carbonaceous Microspheres: A Novel Bifunctional Electrocatalyst for Oxygen Reduction and Evolution Reactions with Ultrahigh Mass Activity

An efficient and robust bifunctional electrocatalyst for both ORR and OER is highly desired for the applications in renewable energy technologies. Here, we prepare the carbonaceous microspheres (CMSs) by a facile hydrothermal treatment of glucose precursor and then dope the CMSs with La2O3, resulting in a high performance bifunctional electrocatalyst of La2O3@CMSs. In alkaline solution, the La2O3@CMSs catalyzes oxygen reduction reactions (ORR) with an onset potential of 0.80 V versus RHE and an overpotential only of 600 mV to achieve a current density of 1.3 mA cm–2. Meanwhile, oxygen evolution reaction (OER) at La2O3@CMSs electrode occurs at an onset potential of 1.60 V versus RHE and the overpotential is only 370 mV. Also, the as-prepared La2O3@CMSs exhibits high Faraday efficiency and long-term stability toward ORR and OER. Significantly, we demonstrate that La2O3@CMSs possesses surprisingly high mass activity, which is calculated to be 78.4 A g–1 for ORR and 831.5 A g–1 for OER, respectively. A potential window for ORR and OER at the modified electrode is estimated to be 0.80 V, implying a promising bifunctional electrocatalytical performance of La2O3@CMSs. The improvement of the bifunctional electrocatalytical activity may be due to the generation of active component of La–O and C–O at the surface and its synergistic interact with the La2O3@CMSs. This work not only provides a facile strategy for preparing highly efficient bifunctional electrocatalyst, but also offers an insight into the design of metal-oxides doped carbon materials for energy storage and conversion applications.

A brief overview on the 11th National Symposium on New Carbon Materials

The 11th National Symposium on New Carbon Materials was held in Taiyuan, Shanxi, PR China, hosted by the Institute of Coal Chemistry, Chinese Academy of Sciences, during August 16–20, 2013. About 300 attendees participated in the conference, and 142 papers were accepted for discussion, including plenary lectures, keynotes talks, oral presentations and poster presentations. The papers were classified into the following seven topics: carbon fibers and their composites, carbon-based composites, nanostructured carbons, porous carbons, intercalated and modified carbons, carbon materials for energy storage, carbon materials for health and environment protection. Research and development of carbon fibers and their composites, carbon-based composites, and porous carbons are quite active. Rapid progress has also been made on the energy storage applications of carbon materials and nanocarbons.

A brief overview of the Tenth Cross-Strait Symposium on Carbon Materials

The Tenth Cross-Strait Symposium on Carbon Materials was held in Baotou City, Inner Mongolia, PR China from August 1 to 4, 2012. It was hosted by Tsinghua University and Inner Mongolia University of Science & Technology. More than 60 cross-strait carbon scientists participated in the conference, and 31 presentations were given, including 15 keynote talks and 16 oral presentations. The presentations were classified into the following eight topics: highly efficient conversion and applications of coal, carbon fibers and carbon-based composites, special carbon-graphite materials, nano-structured carbons and their applications, carbon materials for energy storage, preparation and applications of graphene, evaluation and performance of new carbon materials, and other new carbon materials. The 4-day symposium has increased cross-strait academic exchange and has advocated close academic cooperation in the field of carbon materials.

Nanographene-Constructed Carbon Nanofibers Grown on Graphene Sheets by Chemical Vapor Deposition: High-Performance Anode Materials for Lithium Ion Batteries

We report on the fabrication of 3D carbonaceous material composed of 1D carbon nanofibers (CNF) grown on 2D graphene sheets (GNS) via a CVD approach in a fluidized bed reactor. Nanographene-constructed carbon nanofibers contain many cavities, open tips, and graphene platelets with edges exposed, providing more extra space for Li(+) storage. More interestingly, nanochannels consisting of graphene platelets arrange almost perpendicularly to the fiber axis, which is favorable for lithium ion diffusion from different orientations. In addition, 3D interconnected architectures facilitate the collection and transport of electrons during the cycling process. As a result, the CNF/GNS hybrid material shows high reversible capacity (667 mAh/g), high-rate performance, and cycling stability, which is superior to those of pure graphene, natural graphite, and carbon nanotubes. The simple CVD approach offers a new pathway for large-scale production of novel hybrid carbon materials for energy storage.

ハイテク二次電池を支える機能性材料の現状と将来 エネルギー貯蔵用カーボン材料の進展

ハイテク二次電池を支える機能性材料の現状と将来 エネルギー貯蔵用カーボン材料の進展