We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Mn3O4 nanoparticles grown selectively on RGO sheets over free particle growth in solution allowed for the electrically insulating Mn3O4 nanoparticles wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ~900mAh/g near its theoretical capacity with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn3O4 nanoparticles grown atop. The Mn3O4/RGO hybrid could be a promising candidate material for high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for design and synthesis of battery electrodes based on highly insulating materials.

Mn3O4-Graphene Hybrid as a High Capacity Anode Material for Lithium Ion Batteries

Application of magnetic chitosan composites for the removal of toxic metal and dyes from aqueous solutions

With the rapid arising of information technology, microwave absorbing materials (MAMs) are playing an increasingly significant role in electronic reliability, healthcare, and national defense security. Hence, development of high performance MAMs with thin thickness, low density, wide bandwidth, and strong absorption has attracted great interests. Recently, taking graphene as MAMs for high-performance electromagnetic (EM) wave attenuation has grabbed considerable attention, owing to their low density, high specific surface area, strong dielectric loss, and high electronic conductivity. Furthermore, in order to address the interfacial impedance mismatching of the sole graphene materials, incorporation of other lossy materials has been widely studied as the imperative solution to improve its MA performance. In this review, we introduce the theory of microwave absorption and summarize recent advances in the fabrication of graphene-based MAMs, including rational design of the microstructure of pure graphene and tunable chemical integrations with polymers, magnetic metals, ferrites, ceramics, and multicomponents composites. The key point of enhancing MA in graphene-based MAMs is to regulate their EM properties, improve of impedance matching, and create diversified loss mechanisms. Furthermore, the shortcomings, challenges, and prospects of graphene-based MAMs are also put forward, which will be helpful to people working in the related fields.

Graphene-based microwave absorbing composites: A review and prospective

Graphene oxide: A promising nanomaterial for energy and environmental applications

A self-assembled spongelike (S) ultralight (ρ ≈ 140 mg cm−3) aerogel was fabricated through polypyrrole (PPy) and reduced graphene oxide (RGO). First, the dispersed graphene oxide (GO) was locked homogeneously in those chains formed by the gelation of PPy. Then, a hydrothermal process was employed to reduce GO to RGO. With a trace content of RGO (0.43 wt% in aerogel), the electromagnetic absorption (EA) performance had been significantly improved. Only with a very low filler loading (10 wt%), the S-PPy/RGO aerogel based composite could reach an effective EA bandwidth (below −10 dB) of 6.76 GHz, and the highest reflection coefficient reached −54.4 dB at 12.76 GHz. It was demonstrated that this aerogel material can be considered as an effective route to design a lightweight and high performance EA material. Furthermore, the S-PPy/RGO aerogel also showed a suitable pollution treatment performance with different solvents and dyes.

Hualin Jiang

Papers

Synthesis of novel nanocomposite Fe3O4/ZrO2/chitosan and its application for removal of nitrate and phosphate

Electromagnetic and microwave absorbing properties of RGO@hematite core-shell nanostructure/PVDF composites

Alkali-free synthesis of a novel heterostructured CeO 2 -TiO 2 nanocomposite with high performance to reduce Cr(VI) under visible light

Photocatalytic degradation of tetracycline by using a regenerable (Bi)BiOBr/rGO composite

Hollow Prussian blue analogue/g-C3N4 nanobox for all-solid-state asymmetric supercapacitor