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Surface and interfacial chemistry is of fundamental importance in functional nanomaterials applied in catalysis, energy storage and conversion, medicine, and other nanotechnologies. It has been a perpetual challenge for the scientific community to get an accurate and comprehensive picture of the structures, dynamics, and interactions at interfaces. Here, some recent examples in the major disciplines of nanomaterials are selected (e.g., nanoporous materials, battery materials, nanocrystals and quantum dots, supramolecular assemblies, drug-delivery systems, ionomers, and graphite oxides) and it is shown how interfacial chemistry can be addressed through the perspective of solid-state NMR characterization techniques.

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Compatible with various common solvents, a new electrolyte salt NaDFOB has been studied, which enables excellent reversible capacity and high rate capability when used in Na/Na0.44MnO2 half cells.

A novel layer-by-layer approach has been developed to synthesize polycrystalline SnO(2) hollow spheres with tunable shell thickness and size using SiO(2) spheres as a template. The surface of the SiO(2) spheres has been first modified by the polyelectrolyte, and subsequently, the compact SnO(2) layer has deposited on the surface of the SiO(2) spheres through a redox reaction because of the electrostatic attraction between the charged species. After HF etching treatment, the uniform SnO(2) hollow spheres have been obtained. The approach presented herein has been extended to synthesize other metal oxide and sulfide hollow spheres such as In(2)O(3) and ZnS. Moreover, the as-synthesized SnO(2) hollow spheres have been applied in lithium-ion battery and show improved performance compared with SnO(2) nanoparticles. The high surface area and stable hollow structure of the SnO(2) hollow spheres may be responsible for the improved performance.

A new class of hydrogen storage materials, borohydride hydrazinates, was successfully synthesized. In particular, the bidentate NH 2 NH 2 coordinates with LiBH 4 in molar ratios of 1 : 1 and 1 : 2 giving rise to a monoclinic LiBH 4 $NH 2 NH 2 and orthorhombic LiBH 4 $2NH 2 NH 2 , respectively. Around 13.0 wt% H 2 can be released from LiBH 4 $NH 2 NH 2 at 140 C in the presence of Fe-B catalysts.Development of safe and energy efficient hydrogen storage materials is one of the technical challenges towards the large scale utilization of hydrogen energy.

The solid electrolyte interface (SEI) formed on the anode is one of the key factors that determine the life span of sodium metal batteries (SMBs). However, the continuous evolution of SEI during charging/discharging processes complicates the fundamental understanding of its chemistry and structure. In this work, we studied the underlying mechanisms of the protection effect offered by the SEI derived from sodium difluoro(oxalato)borate (NaDFOB). In situ nuclear magnetic resonance (NMR) shows that the prior reduction of DFOB anion contributes to the SEI formation, and it suppresses the decomposition of carbonate solvents. Depth-profiling x-ray photoelectron spectroscopy and high-resolution solid-state NMR reveal that the DFOB anion is gradually turned into borate and fluoride-rich SEI with cycling. The protection effect of SEI reaches the optimum at 50 cycles, which triples the life span of SMB. The detailed investigations provide valuable guidelines for the SEI engineering.

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