A simple and scalable process was developed for the synthesis of highly crystalline magnetite nanocrystals embedded in a carbon matrix using low cost starting materials; the resulting nanocomposite showed a very high specific capacity of 863 mA hg⁻¹ in the initial cycle and high capacity retention of 90% after 30 cycles.

Due to various compositions and morphologies, exquisite intrinsic architectures, and renewability, biomass has been used to generate carbon electrodes for supercapacitors.

Sodium‐ion batteries (SIBs) have attracted enormous attention in recent years due to the high abundance and low cost of sodium. However, in contrast to lithium‐ion batteries, conventional graphite is unsuitable for SIB anodes because it is much more difficult to intercolate the larger Na ions into graphite layers. Therefore, it is critical to develop new anode materials for SIBs for practical use. Here, heteroatom‐doped graphene with high doping levels and disordered structures is prepared using a simple and economical thermal process. The solvothermal‐derived graphene shows excellent performance as an anode material for SIBs. It exhibits a high reversible capacity of 380 mAh g⁻¹ after 300 cycles at 100 mA g⁻¹, excellent rate performance 217 mAh g⁻¹ at 3200 mA g⁻¹, and superior cycling performance at 2.0 A g⁻¹ during 1000 cycles with negligible capacity fade.

We introduce a simple process to synthesize few-layered MoS₂ nanosheets supported on coaxial carbon nanotubes through an L-cysteine-assisted hydrothermal route, in which L-cysteine, a cheap and ordinary amino acid, plays a fundamental role in controlling the morphology of the hybrid material and the binder to help the growth of MoS₂ nanosheets on the surface of the carbon nanotubes. It is also demonstrated that the polypeptide formed by L-cysteine can be transformed into amorphous carbon by heat treatment under an inert atmosphere. The materials exhibit high capacity and excellent cycling performance when used as anode materials for lithium ion batteries. The specific capacity of a composite with 1 : 4 molar ratio of MoS₂ to carbon nanotubes is 736.5 mAh g⁻¹ after the first cycle, increased for several initial cycles, and remains at 823.4 mAh g⁻¹ even after 30 cycles, when cycled at a current density of 100 mA g⁻¹. At a very high current density of 1600 mA g⁻¹, the material shows a stable capacity of approximately 530 mAh g⁻¹ after 30 cycles. The noteworthy improvement in the electrochemical performance of the material can be attributed to their unique structure and the synergistic effects of amorphous carbon and few-layered MoS₂.