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A novel three-dimensionally (3D) ordered hierarchically porous polypyrrole (3DOHPPy) is successfully synthesized via a simple chemical polymerization method by using silica colloidal crystals as templates. The 3DOHPPy possesses a large BET specific surface area (118.5 m2 g−1), 3D ordered interconnected macropores (240 nm) and mesopores (2–3 nm) on the macropore walls. The sulfur/3DOHPPy (S/3DOHPPy) composite is prepared by a solution-diffusion route followed by low-temperature heat treatment and studied as a cathode material for the lithium/sulfur (Li/S) battery. The resulting S/3DOHPPy cathode shows a high specific discharge capacity of 751 mAh g−1 even after 100 cycles at 0.1 C and great rate capability. The superior electrochemical property of the S/3DOHPPy composite is ascribed to the unique hierarchical structure of 3DOHPPy with ordered interconnected macropores that benefit enhanced mass transfer and the small mesopores on the macropore walls that can immobilize the sulfur and polysulfides produced during the discharge/charge processes.

A three-dimensional ZnO/graphene/CNT (carbon nanotube) composite was prepared by a one-step sol-gel synthetic technique followed by vacuum-assisted filtration. High resolution transmission electron microscopy revealed the formation of highly-dispersed ZnO nanoparticles, uniformly laid on the crumpled graphene sheets and CNT. The as-prepared ZnO/graphene/CNT composite exhibited excellent cyclability and rate capability when used as anode for lithium ion batteries, affording 620 mAh g −1 stable reversible discharge capacity after 100 cycles at 100 mA g −1 . The unique composite structure provided a large surface area and highly conductive network which maintains good electronic contact between particles, suppresses ZnO aggregation during the charge/discharge processes, and accommodates the large volume changes of ZnO upon cycling.

Ultrafine ZnO nanocrystals anchored on graphene were synthesized by a facile and highly efficient in situ sol-gel method. Uniform ZnO nanocrystals with an average size of 9.3 nm were well dispersed on graphene nanosheets forming two-dimensional nanostructured ZnO/Graphene hybrids. Due to the intimate integration and strong synergistic effects between the ZnO nanocrystals and graphene nanosheets these hybrids exhibited a stable electrochemical performance. Along with this the graphene anchoring provides to the system high conductivity and large surface area and buffers the ZnO volume change during cycling. Furthermore, ultrafine ZnO nanocrystals provide a short diffusion path for Li + upon insertion/deinsertion. These structure and property advantages allow the as-prepared ZnO/graphene composite to exhibit a high reversible operation as an anode for lithium batteries with a stable specific discharge capacity of 516 mAh g −1 after 100 cycles at a current density of 200 mA g −1 and a good rate capability with a discharge capacity of 304 mAhg −1 even at a cycling rate of 1500 mA g −1 .

Highly dispersed ZnO nanoparticles were prepared by a versatile and scalable sol-gel synthetic technique. High-resolution transmission electronic microscopy (HRTEM) showed that the as-prepared ZnO nanoparticles are spherical in shape and exhibit a uniform particle size distribution with the average size of about 7 nm. Electrochemical properties of the resulting ZnO were evaluated by galvanostatic discharge/charge cycling as anode for lithium-ion battery. A reversible capacity of 1652 mAh g−1 was delivered at the initial cycle and a capacity of 318 mAh g−1 was remained after 100 cycles. Furthermore, the system could deliver a reversible capacity of 229 mAh g−1 even at a high current density of 1.5 C. This outstanding electrochemical performance could be attributed to the nano-sized features of highly dispersed ZnO particles allowing for the better accommodation of large strains caused by particle expansion/shrinkage along with providing shorter diffusion paths for Li+ ions upon insertion/deinsertion.

Because the boron (B) concentration in water has an apparent positive correlation with salinity, the B content adsorbed in sediments is often regarded as an important indicator to reconstruct the water salinity in a sedimentary environment. The premise of the quantitative reconstruction of paleosalinity is that the B uptake in sediments is proportional to the B concentration in water; however, the study showed that there is no direct relationship. The B absorption in sediments can be affected by both the content of the clay minerals and the total organic carbon content. The data from testing modern sediments and water samples in the Qinghai Lake show that a higher content in clay minerals is beneficial for B adsorption. Furthermore, the organic carbon from halophiles has a strong effect on the enrichment of B. Therefore, the organic carbon content in sediments should be considered when the paleosalinity of water is reconstructed using its B content. It is also thought that the Adams and Couch formulas are not suitable for reconstructing the salinity of water with a high organic carbon content in sediments because they consider only the effect of clay minerals on the adsorbed B without the contribution of organic carbon.

Hexagonal ZnO nanoplates were synthesizedviasimple one-pot hydrothermal reaction of Zn(CH3COO)2and CO(NH2)2. XRD, SEM, and HRTEM were used to investigate the composition and microstructure of the material. Together with the facile strain relaxation during structure and volume change upon cycling, this plate-like structure of ZnO is favorable for physical and chemical interactions with lithium ions because of its large contact area with the electrolyte, providing more active sites and short diffusion distances. The resulting hexagonal ZnO nanoplates electrode exhibited good cyclability and delivered a reversible discharge capacity of 368 mAh g−1after 100 cycles at 0.1 C.