Developing a composite electrode containing both carbon and transition metal/metal oxide as the supercapacitor electrode can combine the merits and mitigate the shortcomings of both the components. Herein, we report a simple strategy to prepare the hybrid nanostructure of Co@Carbon and Co3O4@Carbon by pyrolysis a single MOFs precursor. Co-based MOFs (Co-BDC) nanosheets with morphology of regular parallelogram slice have been prepared by a bottom-up synthesis strategy. One-step pyrolysis of Co-BDC, produces a porous carbon layer incorporating well-dispersed Co and Co3O4 nanoparticles. The as-prepared cobalt-carbon composites exhibit the thin layer morphology and large specific surface area with hierarchical porosity. These features significantly improve the ion-accessible surface area for charge storage and shorten the ion transport length in thin dimension, thus contributing to a high specific capacitance. Improved capacitance performance was successfully realized for the asymmetric supercapacitors (ASCs) (Co@Carbon//Co3O4@Carbon), better than those of the symmetric supercapacitors (SSCs) based on Co@Carbon and Co3O4@Carbon materials (i.e., Co@Carbon//Co@Carbon and Co3O4@Carbon//Co3O4@Carbon). The working voltage of the ASCs can be extended to 1.5 V and show a remarkable high power capability in aqueous electrolyte. This work provides a controllable strategy for nanostructured carbon-metal and carbon-metal oxide composite electrodes from a single precursor.

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Continuous antisolvent crystallization of Dolutegravir Sodium was studied using a novel device integrating the microfluidic continuous crystallizer and the agitated crystallizer. This study successfully minimized the risks of channel blockage during continuous crystallization by innovating an approach to isolate crystal nucleation from subsequent crystal growth. We systematically investigated the effects of the antisolvent content, channel width, and stirring speed on the particle size, the crystal size distribution (CSD), and the morphology of the crystals. By optimization of experimental parameters, crystals can be continuously obtained with small particle sizes (D 50 values of 5−10 μm), narrow CSDs (widths of 4−7 μm), and prismatic morphologies by this apparatus and approach. The particle sizes D 50 and CSDs of crystals are reduced by 30% and 60% at least, respectively, compared with values of the commercial sample. Small and uniform crystals are particularly desirable in the pharmaceutical industry, which can significantly improve drug solubility, bioavailability, corresponding pharmacokinetic performance, and the properties of the tablet.