•Hydrous alumina was coated on P.R. 170 particle surface by hydrolysis of Al2(SO4)3.•P.R. 170 was coated with three types of structure; dots, floccules and films.•The relationship between the coating structures and the properties of P.R. 170 are discussed.•The film coating most significantly improves the properties of P.R. 170.C.I. Pigment Red 170 (P.R. 170) is one of the widely used organic pigments, and surface modification is essential to improve its thermal stability, and solvent resistance. In this work, hydrous alumina was coated onto P.R. 170 particles by hydrolysis of Al2(SO4)3, and different coating structures/morphologies were obtained including dots, floccules and films with different thickness. The influence of pH, temperature and Al2(SO4)3 content on the hydrous alumina coating structures were investigated by transmission electron microscopy (TEM), ζ-potential analysis, and several spectroscopic techniques. Thermogravimetric analysis (TGA) and pigment bleeding tests indicated that the thermal stability and solvent resistance of the pigments can be remarkably improved by a film coating, and this reveals that the consecutiveness and density of the coating layers should be the key factors for improvement of the organic pigments.

Nanoporous graphene sheets were generated through a simple thermal annealing procedure using composites of ferrocene nanoparticles and graphene oxide sheets as precursors in a large scale. The morphology, composition, and formation mechanism of the as-obtained nanoporous graphene sheets were studied complementarily with scanning electron microscopy, transmission electron microscopy, X-ray powder diffraction, and other spectroscopy techniques. We found that the density of nanopores on the graphene sheet was determined by the surface distribution of oxygen-containing groups on the original graphene oxide sheets. The coin cells using nanoporous graphene sheets as anode materials showed higher specific lithium ion storage capacity, better discharge/charge rate capability and higher cycling stability when compared to the coin cells with graphene or chemically reduced graphene sheets as anodes.

Novel boron-doped carbon nanosheets were prepared through a facile hydrothermal method using glucose and sodium borohydride as precursors. Taking structural advantage of the as-prepared boron-doped carbon nanosheets, high density Fe3O4 nanoneedle arrays were generated on them, resulting in the composites of boron-doped carbon nanosheets/Fe3O4 nanoneedles. The nanoneedle-like morphology and the unique perpendicular orientation of the Fe3O4 nanoneedles largely suppressed the aggregation of the boron-doped carbon nanosheets in the composites. Therefore, as lithium ion battery anodes, the composites exhibited an excellent lithium ion storage capacity, high rate capability, and decent discharge/charge cycling stability. It was demonstrated that the reversible specific capacity can reach 1132 mA h g−1 at the charge/discharge current density of 0.1 A g−1, and it can be maintained at 980 mA h g−1 after 400 cycles. Even at a high current density of 10 A g−1, the reversible capacity was still retained above 350 mA h g−1, which is much higher than that of other carbon and Fe3O4 composites reported so far. These results render the as-prepared composite as an ideal anode material for high performance lithium ion batteries.

Graphene sheets coated with a thin layer of nitrogen-enriched carbon possess excellent rate capability and cycle performance at various current rates as anodes for LIBs, as the nitrogen-enriched carbon not only incorporates the nitrogen atoms, but also reduces the aggregation of graphene sheets, which can facilitate the storage and transportation of the lithium within the anode.

It is challenging to develop lithium ion batteries (LIBs) possessing simultaneously large reversible capacity, high rate capability, and good cycling stability, which are in turn determined mainly by the component materials of batteries. We designed and synthesized a series of composites of chemically-reduced graphene oxide (CRG) sheets and carbon nanospheres (CNS). It was illustrated that within the as-obtained composites the CNSs were fully cladded and bridged with CRG sheets forming a three-dimensional (3D) network with cavities and pores. Coin cells using the anodes made of the as-obtained composites with appropriate composition exhibit large reversible capacity, high rate capability, and good cycling stability. The highest reversible specific capacity could reach up to 925 mA h g−1 and 604 mA h g−1 at charge–discharge current densities of 5 A g−1 and 10 A g−1, respectively, and faint capacity and rate capability fades were detected even after 200 charge–discharge cycles. The excellent electrochemical performance of the anodes made of the as-obtained composites in the LIBs originates from the unique 3D network structure and the intrinsic properties of CRG and CNS that provide plenty of transportation pathways for electron and Li+, and sufficient tolerant sites for Li/Li+.

Novel boron-doped carbon nanosheets were prepared through a facile hydrothermal method using glucose and sodium borohydride as precursors. Taking structural advantage of the as-prepared boron-doped carbon nanosheets, high density Fe3O4 nanoneedle arrays were generated on them, resulting in the composites of boron-doped carbon nanosheets/Fe3O4 nanoneedles. The nanoneedle-like morphology and the unique perpendicular orientation of the Fe3O4 nanoneedles largely suppressed the aggregation of the boron-doped carbon nanosheets in the composites. Therefore, as lithium ion battery anodes, the composites exhibited an excellent lithium ion storage capacity, high rate capability, and decent discharge/charge cycling stability. It was demonstrated that the reversible specific capacity can reach 1132 mA h g−1 at the charge/discharge current density of 0.1 A g−1, and it can be maintained at 980 mA h g−1 after 400 cycles. Even at a high current density of 10 A g−1, the reversible capacity was still retained above 350 mA h g−1, which is much higher than that of other carbon and Fe3O4 composites reported so far. These results render the as-prepared composite as an ideal anode material for high performance lithium ion batteries.

It is challenging to develop lithium ion batteries (LIBs) possessing simultaneously large reversible capacity, high rate capability, and good cycling stability, which are in turn determined mainly by the component materials of batteries. We designed and synthesized a series of composites of chemically-reduced graphene oxide (CRG) sheets and carbon nanospheres (CNS). It was illustrated that within the as-obtained composites the CNSs were fully cladded and bridged with CRG sheets forming a three-dimensional (3D) network with cavities and pores. Coin cells using the anodes made of the as-obtained composites with appropriate composition exhibit large reversible capacity, high rate capability, and good cycling stability. The highest reversible specific capacity could reach up to 925 mA h g−1 and 604 mA h g−1 at charge–discharge current densities of 5 A g−1 and 10 A g−1, respectively, and faint capacity and rate capability fades were detected even after 200 charge–discharge cycles. The excellent electrochemical performance of the anodes made of the as-obtained composites in the LIBs originates from the unique 3D network structure and the intrinsic properties of CRG and CNS that provide plenty of transportation pathways for electron and Li+, and sufficient tolerant sites for Li/Li+.