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Solvent molecules, especially coordinated solvent molecules, vastly affect the energetic properties of energetic coordination polymers (ECPs). Therefore, an effective strategy to maintain energetic properties is to reduce solvent molecules. In this paper, a nitrogen-rich energetic coordination polymer [Cu(HBTT)(H2O)]n (ECP 1) was synthesized and prepared by integrating the coordination mode. Its properties were adequately investigated, including crystal structure, thermal stability, energetic properties, and sensitivity. In terms of application, it was researched as catalysts for the thermal decomposition of AP and as a primary explosive for laser initiation. As revealed by single-crystal X-ray diffraction results, it crystallizes in and belongs to monoclinic space group P21/n with a 2D layer-like structure. Meanwhile, it has outstanding thermal stability (Tp = 357.2 °C, Ek = 201.78 kJ mol-1) according to differential scanning calorimetry (DSC) curves and thermogravimetric curves (TG). The detonation velocity and detonation pressure of ECP 1 (8.63 km s-1, 36.73 GPa) can bear comparison with RDX and HMX. The catalytic pyrolysis experiment indicates that AP/ECP 1 (10 wt%) can accelerate the thermal decomposition of AP, with the high temperature for decomposition decreasing to nearly 80 °C. The activation energy (Ek) of AP decreased from 217.36 kJ mol-1 to 185.96 kJ mol-1 by adding ECP 1. Meanwhile, ECP 1 has a preliminary response to laser initiation. These results are conducive to the quick development of ECPs.

Plant-derived carbon (C) inputs via foliar litter, root litter and root exudates are key drivers of soil organic C stocks. However, the responses of these three input pathways to climate warming have rarely been studied in alpine shrublands. By employing a 3-year warming experiment (increased by 1.3 °C), we investigated the effects of warming on the relative C contributions from foliar litter, root litter and root exudates from Sibiraea angustata , a dominant shrub species in an alpine shrubland on the eastern Qinghai-Tibetan Plateau. The soil organic C inputs from foliar litter, root litter and root exudates were 77.45, 90.58 and 26.94 g C m−2, respectively. Warming only slightly increased the soil organic C inputs from foliar litter and root litter by 8.04 and 11.13 g C m−2, but significantly increased the root exudate C input by 15.40 g C m−2. Warming significantly increased the relative C contributions of root exudates to total C inputs by 4.6% but slightly decreased those of foliar litter and root litter by 2.5% and 2.1%, respectively. Our results highlight that climate warming may stimulate plant-derived C inputs into soils mainly through root exudates rather than litter in alpine shrublands on the Qinghai-Tibetan Plateau. [ABSTRACT FROM AUTHOR]

Rational design of novel structures plays a key role in achieving high specific capacities and fast charge rates with a long cycling life for battery-type electrodes of supercapacitors. To tackle capacity fading issues of battery-type electrode materials for supercapacitors, a new approach is proposed to form a bioinspired sea-sponge nanostructure of Ni/Ni(HCO3)2-on-C, synthesized through modifying triangle nanoflakes of Ni(HCO3)2 with partially in situ reduced Ni generated on sea-sponge-like porous carbon spheres (S-PCSs). The conductive skeleton of S-PCSs facilitates fast electron transfer and ion diffusion, and maintains the morphology of Ni(HCO3)2 triangle nanoflakes to ensure a high specific capacity of Ni/Ni(HCO3)2 nanoflakes. Simultaneously, the in situ reduced Ni acts as a capacity reservoir to prevent the fading of the specific capacity. When, applied as a positive electrode material, such sea-sponge nanostructures of Ni/Ni(HCO3)2-on-C exhibit a high specific capacity (472 mA h g−1) with a good rate capability (66% capacity retention at 32 A g−1vs. 8 A g−1), superior reversibility and cyclability (92% capacity retention after 10 000 cycles). An asymmetric supercapacitor based on Ni/Ni(HCO3)2-on-C//S-PCSs shows a high energy density of 51.3 W h kg−1 at a power density of 4 kW kg−1 with a capacitance retention of 89.6% over 6000 cycles. [ABSTRACT FROM AUTHOR]