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61.
Selection of the friction electrode materials is crucial to the performance of a triboelectric nanogenerator (TENG). In the present study, a metal–organic coordination complex containing organosulfonate counteranions with electron-donating ability was synthesized through the coordination-driven self-assembly approach under mild reaction conditions and was chosen as a positive electrode material to construct a triboelectric nanogenerator, exhibiting high-output performance with a peak value of short circuit current density of 98.6 μA and an output voltage of 1180 V. As a practical application, it was shown to light up 1488 commercial green LEDs and power an anticorrosion system device to protect metals from corrosion.  相似文献   
62.
Covalent organic frameworks (COFs) enable precise integration of various organic building blocks into porous skeletons through topology predesign. Here, we report the first example of COFs by integrating electron withdrawing bromine group onto the skeletons for triboelectric nanogenerators (TENG). The resulting framework exhibits high surface area and good crystallinity. Thus, the bromine functionalized COF has more regular aligned π columns and arrays over the skeleton than bare COFs, which in turn significantly enhances charge transport ability. As a result, bromine functionalized COFs showed higher electrical output performance at 5 Hz with a peak value of short circuit current density of 43.6 μA and output voltage of 416 V, which is 2 and 1.3 times higher than those of bare COFs (21.6 μA and 318 V), respectively. These results demonstrated that this strategy for engineering electron withdrawing groups on the skeleton could open a new aspect of COFs for developing TENG devices.  相似文献   
63.
Rapid and selective removal of micropollutants from water is important for the reuse of water resources. Despite hollow frameworks with specific functionalized porous walls for the selective adsorption based on a series of interactions, tailoring a stable shape of nanometer- and micrometer-sized architectures for the removal of specific pollutants remains a challenge. Here, exactly controlled sheets, tubes, and spherical frameworks were presented from the crosslinking of supramolecular colloids in polar solvents. The frameworks strongly depended on the architecture of original supramolecular colloids. As the entropy of colloids increased, the initial laminar framework rolled up into hollow tubules, and then further curled into hollow spheres. These shape-persistent frameworks showed unprecedented selectivity as well as specific recognition for the shape of pollutants, thus contributing to efficient pollutant separation.  相似文献   
64.
65.
As a highly stable band gap semiconductor, antimonene is an intriguing two‐dimensional (2D) material in optoelectronics. However, its short layer distance and strong binding energy make it challenging to prepare high‐quality large 2D antimonene; therefore, its predicted tunable band gap has not been experimentally confirmed. Now, an approach to prepare smooth and large 2D antimonene with uniform layers that uses a pregrinding and subsequent sonication‐assisted liquid‐phase exfoliation process has been established. Mortar pregrinding provides a shear force along the layer surfaces, forming large, thin antimony plates, which can then easily be exfoliated into smooth, large antimonene, avoiding long sonication times and antimonene destruction. The resulting antimonene also enabled verification of the tunable band gap from 0.8 eV to 1.44 eV. Hole extraction and current enhancement by about 30 % occurred when the antimonene was used as a hole transport layer in perovskite solar cells.  相似文献   
66.
A N-bromosuccinimide (NBS) mediated decarboxylative sulfonylation of β-keto acids with sodium sulfinates is developed. The transformation exhibits a broad substrate scope and good functional group tolerance. Preliminary mechanistic studies showed that this reaction is likely to proceed through a nucleophilic substitution of β-keto acid with sulfonyl bromide pathway. All synthesized β-keto sulfones were evaluated the inhibitory effect against human carboxylesterase 1 (CES1). This investigation offers an expedient strategy for efficient synthesis of β-keto sulfones that are widely present in biologically active natural products and pharmaceutical agents.  相似文献   
67.
In this paper, a new monotonicity, MM-monotonicity, is introduced, and the resolvent operator of an MM-monotone operator is proved to be single valued and Lipschitz continuous. With the help of the resolvent operator, an equivalence between the variational inequality VI(C,F+G)(C,F+G) and the fixed point problem of a nonexpansive mapping is established. A proximal point algorithm is constructed to solve the fixed point problem, which is proved to have a global convergence under the condition that FF in the VI problem is strongly monotone and Lipschitz continuous. Furthermore, a convergent path Newton method, which is based on the assumption that the projection mapping C(⋅)C() is semismooth, is given for calculating εε-solutions to the sequence of fixed point problems, enabling the proximal point algorithm to be implementable.  相似文献   
68.
The 2-alkoxyimidate-1,10-phenanthroline complexes of manganese, cobalt and nickel have been synthesized by the reaction of 2-cyano-1,10-phenanthroline with metal dichloride in the corresponding alcohol. The metal complexes bearing two 2-cyano-1,10-phenanthrolines were isolated in non-protonic solvent as the coordination around metal core with two ligands and two chlorides. The alkoxyimidation of nitrile linked on ligand was speeded in forming the 2-alkoxyimidate-1,10-phenanthrolinyl metal complexes. All the complexes have been characterized by FT-IR spectra and elemental analysis, and some of their structures have also been confirmed by single-crystal X-ray diffraction analysis. All the metal complexes were evaluated in the catalytic oligomerization of ethylene with some alkylaluminums as co-catalyst; in which manganese complexes were less active, cobalt complexes showed low to moderate activities, and nickel complexes gave moderate to good activities.  相似文献   
69.
Without excess Li, anode-free Li-metal batteries (AFLMBs) have been proposed as the most likely solution to realizing highly-safe and cost-effective Li-metal batteries. Nevertheless, short cyclic life puzzles conventional AFLMBs due to anodic dead Li accumulation with a local current concentration induced by irreversible electrolyte depletion, insufficient active Li reservoir and slow Li+ transfer at the solid electrolyte interphase (SEI). Herein, SrI2 is introduced into carbon paper (CP) current collector to effectively suppress dead Li through synergistic mechanisms including reversible I/I3 redox reaction to reactivate dead Li, dielectric SEI surface with SrF2 and LiF to prevent electrolyte decomposition and highly ionic conductive (3.488 mS cm−1) inner layer of SEI with abundant LiI to enable efficient Li+ transfer inside. With the SrI2-modified current collector, the NCM532/CP cell delivers unprecedented cyclic performances with a capacity of 129.2 mAh g−1 after 200 cycles.  相似文献   
70.
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