Search

Although there have been many studies on asymmetric supercapacitors (ASCs), anode materials are still mainly carbon-based. However, carbon-based materials with low specific capacitance cannot match the cathode materials, limiting the energy density of ASCs. In this research, a low-cost and environmentally friendly anode of homogeneous α-Fe2O3 nanoparticles grown on three-dimensional graphene (3DG) hydrogel is synthesized, with significant specific capacitance (788.6 F g−1 at 1 A g−1) and exceptionally good stability (retaining 82.3% capacitance after 5000 cycles). The composite material of NiCo2O4 nanorods grown on 3DG (NiCo2O4/3DG) has been prepared as the cathode by a similar method. The NiCo2O4/3DG also shows excellent electrochemical performance (1264.3 F g−1 at 1 A g−1 and stability of 91.7% after 5000 cycles). Furthermore, the ASCs of NiCo2O4/3DG//α-Fe2O3/3DG, which is composed of the as-prepared cathode and anode materials, exhibits excellent energy density of 77.8 W h kg−1 at a power density of 800 W kg−1, and outstanding stability of 81.6% after 5000 cycles at 10 A g−1. Therefore, this proves that α-Fe2O3/3DG is a promising anode material for supercapacitors. [ABSTRACT FROM AUTHOR]

Articular cartilage lacks a blood supply and nerves. Hence, articular cartilage regeneration remains a major challenge in orthopedics. Decellularized extracellular matrix- (ECM-) based strategies have recently received particular attention. The structure of native cartilage exhibits complex zonal heterogeneity. Specifically, the development of a tissue-engineered scaffold mimicking the aligned structure of native cartilage would be of great utility in terms of cartilage regeneration. Previously, we fabricated oriented PLGA/ACECM (natural, nanofibrous, articular cartilage ECM) composite scaffolds. In vitro, we found that the scaffolds not only guided seeded cells to proliferate in an aligned manner but also exhibited high biomechanical strength. To detect whether oriented cartilage regeneration was possible in vivo, we used mesenchymal stem cell (MSC)/scaffold constructs to repair cartilage defects. The results showed that cartilage defects could be completely regenerated. Histologically, these became filled with hyaline cartilage and subchondral bone. Moreover, the aligned structure of cartilage was regenerated and was similar to that of native tissue. In conclusion, the MSC/scaffold constructs enhanced the structure-specific regeneration of hyaline cartilage in a rabbit model and may be a promising treatment strategy for the repair of human cartilage defects. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) porous structure that designed based on MnCo 2 O 4 decorated graphene was synthesized by a two-step method. The precursor was prepared of MnCo 2 O 4 by solid phase synthesis method, then in the hydrothermal reaction course, the graphene nanosheets as well as this precursor were self-assembled into a 3D interconnected network. The resultant composite materials present a higher specific capacitance (503 F g−1 at 1 A g−1 current density) and an excellent cycling stability. After 5000 charge/discharge cycles at a current density of 10 A g−1, 97.4% of the specific capacitance was retained. Thus, this material has a promising application potential for supercapacitor, at the same time, this synthetic method can also provide an idea for synthesizing composites based on 3D graphene in the future. • Three-dimensional composites of MnCo 2 O 4 and graphene were synthesized. • Three-dimensional graphene provides a porous skeleton. • The MnCo 2 O 4 /3DG electrode exhibits excellent electrochemical properties. • The excellent supercapacitor performance is attributed to the synergistic effect. [ABSTRACT FROM AUTHOR]