Na‐ion capacitors have attracted extensive interest due to the combination of the merits of high energy density of batteries and high power density as well as long cycle life of capacitors. Here, a novel Na‐ion capacitor, utilizing TiO2@CNT@C nanorods as an intercalation‐type anode and biomass‐derived carbon with high surface area as an ion adsorption cathode in an organic electrolyte, is reported. The advanced architecture of TiO2@CNT@C nanorods, prepared by electrospinning method, demonstrates excellent cyclic stability and outstanding rate capability in half cells. The contribution of extrinsic pseudocapacitance affects the rate capability to a large extent, which is identified by kinetics analysis. A key finding is that ion/electron transfer dynamics of TiO2@CNT@C could be effectively enhanced due to the addition of multiwalled carbon nanotubes. Also, the biomass‐derived carbon with high surface area displays high specific capacity and excellent rate capability. Owing to the merits of structures and excellent performances of both anode and cathode materials, the assembled Na‐ion capacitors provide an exceptionally high energy density (81.2 W h kg−1) and high power density (12 400 W kg−1) within 1.0–4.0 V. Meanwhile, the Na‐ion capacitors achieve 85.3% capacity retention after 5000 cycles tested at 1 A g−1.

Metal-free boron- and carbon-based catalysts for the oxidative dehydrogenation of light alkanes is reviewed from the preparation methods, characterization, catalytic performance and mechanistic issues.

Homogeneous ultrasmall T-Nb O nanocrystallites encapsulated in 1D carbon nanofibers (T-Nb O /CNFs) are prepared through electrospinning followed by subsequent pyrolysis treatment. In a Na half-cell configuration, the obtained T-Nb O /CNFs with the merits of unique microstructures and inherent pseudocapacitance, deliver a stable capacity of 150 mAh g at 1 A g over 5000 cycles. Even at an ultrahigh charge-discharge rate of 8 A g , a high reversible capacity of 97 mAh g is still achieved. By means of kinetic analysis, it is demonstrated that the larger ratio of surface Faradaic reactions of Nb O at high rates is the major factor to achieve excellent rate performance. The prolonged cycle durability and excellent rate performance endows T-Nb O /CNFs with potentials as anode materials for sodium-ion batteries.

Oriented SnS nanoflakes were bound on S-doped N-rich carbon nanosheets to increase pseudocapacitance, and this composite delivers high Na-storage capacity and excellent rate capability.

Hexagonal boron nitride (h-BN) has lately received great attention in the oxidative dehydrogenation (ODH) reaction of propane to propylene for its extraordinary olefin selectivity in contrast to metal oxides. However, high crystallinity of commercial h-BN and elusive cognition of active sites hindered the enhancement of utilization efficiency. Herein, four kinds of plasmas (N 2 , O 2 , H 2 , Ar) were accordingly employed to regulate the local chemical environment of h-BN. N 2 -treated BN exhibited a remarkable activity, i.e., 26.0 % propane conversion with 89.4 % selectivity toward olefins at 520 8C. Spectroscopy demonstrated that "three-boron center" N-defects in the catalyst played a pivotal role in facilitating the conversion of propane. While the sintering effect of the "BO x " species in O 2 -treated BN, led to the suppressed catalytic performance (12.4 % conversion at 520 8C).

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h i g h l i g h t sHeterogeneous aqueous reactions during haze events was investigated. The conversion of gas-phase of S and N to particle-phase was analyzed. Relationships were given between conversion ratio of S, N with RH and O 3 . Evolution of aerosol composition and particle size were analyzed. a b s t r a c tThe effect of heterogeneous aqueous reactions on the secondary formation of inorganic aerosols during haze events was investigated by analysis of comprehensive measurements of aerosol composition and concentrations [e.g., particular matters (PM 2.5 ), nitrate (NO 3 ), sulfate (SO 4 ), ammonium (NH 4 )], gas-phase precursors [e.g., nitrogen oxides (NOx), sulfur dioxide (SO 2 ), and ozone (O 3 )], and relevant meteorological parameters [e.g., visibility and relative humidity (RH)]. The measurements were conducted in Beijing, China from Sep. 07, 2012 to Jan. 16, 2013. The results show that the conversion ratios of N from NOx to nitrate (N ratio ) and S from SO 2 to sulfate (S ratio ) both significantly increased in haze events, suggesting enhanced conversions from NOx and SO 2 to their corresponding particle phases in the late haze period. Further analysis shows that N ratio and S ratio increased with increasing RH, with N ratio and S ratio being only 0.04 and 0.03, respectively, when RH < 40%, and increasing up to 0.16 and 0.12 when RH reached 60e80%, respectively. The enhanced conversion ratios of N and S in the late haze period is likely due to heterogeneous aqueous reactions, because solar radiation and thus the photochemical capacity are reduced by the increases in aerosols and RH. This point was further affirmed by the relationships of N ratio and S ratio to O 3 : the conversion ratios increase with decreasing O 3 concentration when O 3 concentration is lower than <15 ppb but increased with increasing O 3 when O 3 concentration is higher than 15 ppb. The results suggest that heterogeneous aqueous reactions likely changed aerosols and their precursors during the haze events: in the beginning of haze events, the precursor gases accumulated quickly due to high emission and low reaction rate; the occurrence of heterogeneous aqueous reactions in the late haze period, together with the accumulated high concentrations of precursor gases such as SO 2 and NOx, accelerated the formation of secondary inorganic aerosols, and led to rapid increase of the PM 2.5 concentration.

Flexible batteries, which maintain their functions potently under various mechanical deformations, attract increasing interests due to the potential applications in emerging portable and wearable electronics. Significant efforts have been devoted to material synthesis and structural designs to realize the mechanical flexibility of various batteries. Carbon nanotubes (CNTs) have a unique one-dimensional (1D) nanostructure and are convenient to further assemble into diverse macroscopic structures, such as 1D fibers, 2D films, and 3D sponges/aerogels. Due to their outstanding mechanical and electrical properties, CNTs and CNT-based hybrid materials are superior building blocks for different components in flexible batteries. This review summarizes recent progress on the application of CNTs in developing flexible batteries, from closed-system to open-system batteries, with a focus on different structural designs of CNT-based material systems and their roles in various batteries. We also provide perspectives on the challenges and future research directions for realizing practical applications of CNT-based flexible batteries.