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A SiCN-graphene nanocomposite anode material is designed and synthesized by the insertion of graphene sheets into the ceramic network of silicon carbonitride for the development of structurally and electrochemically stable lithium ion batteries. SiCN-graphene composite synthesis was achieved through controlled pyrolysis of poly(silylcarbondiimide)-derived SiCN on graphene surfaces that resulted in formation of a graphene supported ceramic SiCN-graphene architecture, in which graphene works as the layered base supporting the SiCN clusters. SiCN-graphene anode showed a stable charge-discharge capacity of 475.1 mA h g À1 after 100 cycles at a current density of 40 mA g À1 , which is 6.2 times that of bare SiCN anode (76.1 mA h g À1 ). The average coulombic efficiency (excluding the first cycle loss) was 97.93%. Moreover, SiCN-graphene anode showed improved high-rate capability. At 2 C rate (a current density of 800 mA g À1 ), the capacity of SiCN-graphene was above 260 mA h g À1 , while the bare SiCN was observed to be only 2.3 mA h g À1 at the same charge-discharge condition. Improved electrochemical performances of SiCN-graphene are attributed to the presence of graphene which works as the supporting layers to stabilize the SiCN matrix and alleviate the expansion of material structure during charge-discharge cycling.

A simple route for the preparation of ZnS nanocrystal/reduced graphene oxide (ZnS/RGO) by a hydrothermal synthesis process was achieved. The chemical composition, morphology, and structural characterization reveal that the ZnS/RGO composite is composed of sphalerite-phased ZnS nanocrystals uniformly dispersed on functional RGO sheets with a high specific surface area. The ZnS/RGO composite was utilized as an anode in the construction of a high-performance lithium-ion battery. The ZnS/RGO composite with appropriate RGO content exhibits a high reversible specific capacity (780 mA h g), excellent cycle stability over 100 cycles (71.3% retention), and good rate performance at 2C (51.2% of its capacity when measured at a 0.1C rate). To further investigate this ZnS/RGO anode for practical use in full Li-ion cells, we tested the electrochemical performance of the ZnS/RGO anode at different cut-off voltages for the first time. The presence of RGO plays an important role in providing high conductivity as well as a substrate with a high surface area. This helps alleviate the typically problems associated with volume expansion and shrinkage during prolonged cycling. Additionally, the RGO provides multiple nucleation points that result in a uniformly dispersed film of nanosized ZnS that covers its surface. Thus, the high surface area RGO enables high electronic conductivity and fast charge transfer kinetics for ZnS lithiation/delithiation.

Three Cd(II)-based coordination polymers 1− 3 with unique structures and topologies have been successfully constructed under solvothermal conditions by use of a newly designed N-containing rigid triangular ligand tris(4-(4H-1,2,4triazol-4-yl)phenyl)amine (TTPA-4), wherein the structural interpenetration can be modulated by aromatic dicarboxylate coligands including thiophene-2,5-dicarboxylic acid (TDA) and terephthalic acid (TPA). Without using coligands, a noninterpenetrating porous 3-D network of 1 with nia topology was obtained. With the aid of the V-shaped TDA coligand, a 4-fold interpenetrating 3-D network of 2 resulted that is built from (2,3,7)-connecting (4 2 .6)(4 4 .6.8 8 .10 4 .12 4 )-(4) 2 net. In the presence of the linear TPA auxiliary ligand, an 8-fold interpenetrating 3-D network of 3 was produced that is assembled by 3-connecting uninodal srs net. Particularly, compound 1 displays interesting dual function as the result of its unique structural attributes, which not only shows superb sensitivity for nitroaromatics (NACs) with phenolic group but also impressive removal capabilities of toxic Cr 2 O 7 2− oxoanion pollutant from aqueous solution.

Porous silicon carbonitride (SiCN) ceramics were pyrolyzed from poly(silylcarbondiimide) derivatives, followed by etching with different concentrations of HF aqueous solution (5, 10, 15 and 20 wt%). The morphologies, structures and electrochemical performances of the HF-etched SiCN materials were investigated. The results indicated that the surface of the HF-etched SiCN composites became rough and porous. SiCN-10-HF, one of four HF-etched SiCN samples, showed excellent electrochemical properties as an anode for lithium ion batteries. Charge-discharge measurements indicated that the SiCN-10-HF anode exhibited a high initial specific discharge capacity of 681 mA h g À1 at a current density of 40 mA g À1 , which was 2.4 times that of the unetched SiCN anode. After 100 cycles, the discharge capacity of SiCN-10-HF anode delivered 229.3 mA h g À1 , which was 5.0 times that of the unetched SiCN anode (45.6 mA h g À1 ). Additionally, the SiCN-10-HF anode exhibited high rate performance. At a current density of 190 mA g À1 , the discharge capacity of the anode was 160 mA h g À1 .It was deduced that the formation of nano-sized pores or holes on the surface of the SiCN materials in the HF-etching process not only offered new channels for the intercalation of Li + but also relieved the volume expansion during the charge and discharge process, resulting in improved capacity, stable cycling and good rate capability.