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Construction of porous nanosheet arrays of transition‐metal sulfides (TMSs) holds great potential for energy storage. Herein, a one‐step hydrothermal process is employed for the construction of porous Ni1.43Fe.5Co.5S.97 nanosheet arrays (NFCS‐NS) on the nickel foam as a proper positive electrode for hybrid supercapacitor. Owing to the appealing structural features, the NFCS‐NS depicts a high capacity of 1156 C g−1 at 2 A g−1, desirable rate capability of 81.1 %, and significant cyclability of 92.9 %. Also, a promising hybrid device (NFCS‐NS//AC) based on NFCS‐NS and activated carbon (AC) represents a reasonable energy density of 57.3 Wh kg−1 at 807.04 W kg−1 and a notable power density of 20000 W kg−1 at 40 Wh kg−1. Therefore, our current research can introduce an effective strategy for the fabrication of high‐performance electrodes with porous architectures. [ABSTRACT FROM AUTHOR]

Abstract: Rational construction of electrode materials with exclusive structures and compositions are highly attractive for improving the electrochemical properties of supercapacitors (SCs). In the present study, we demonstrate the construction of unique core–shell Ni−Mn−Co−S@Co(OH)2 nanoarrays on nickel foam (denoted as NMCS@COH/NF) as an attractive battery‐type electrode material for SCs through the hydrothermal and electrodeposition strategies, in which the Ni−Mn−Co−S nanowires are well wrapped in the Co(OH)2 shells. Benefiting from the attractive structural properties, the NMCS@COH/NF electrode exhibits considerable electrochemical properties in the aspects of reasonable rate performance (80.3 % up to 24 A g−1), long‐term cyclability (retention rate of 93.3 % undergoing 10 000 cycles), and exceptional capacity (284.85 mAh g−1 at 2 A g−1). Subsequently, the NMCS@COH electrode is assembled into a hybrid supercapacitor, which delivers a good energy density of 51.1 Wh kg−1 at 751.47 W kg−1 and a maximum power density of 18411.76 W kg−1 at 31.3 Wh kg−1. This work provides a straightforward route to rational construction of the electrode materials with promising structural and electrochemical properties for SC applications. [ABSTRACT FROM AUTHOR]

Electrode materials with unique nanoarchitecture, great conductivities, and desirable mechanical stabilities are essential for developing nearly all energy storage devices (ESDs). Herein, a low‐cost route for the fabrication of double‐layer CuCo2S4@Ni−Mo−S (CCS@NMS) nanosheet arrays as an advanced binder‐free positive electrode for supercapattery is presented. The CCS@NMS porous nanoarchitecture has the advantages of good ion diffusion and excellent electronic transport. Accordingly, when employed as battery‐type electrode in supercapattery device, the CCS@NMS electrode reflects amazing capacity (Cs) of 446.3 mAh g−1 (3213.6 F g−1) at 1 A g−1 and 375.8 mAh g−1 (2705.85 F g−1) at 18 A g−1, and 98.2 % of the Cs was still maintained at 6 A g−1 after 5000 cycles, which are higher than that of CCS electrode. Most importantly, using the CCS@NMS electrode as the positive electrode and active carbon (AC) as the negative electrode, the device indicates notable Cs of 66.8 mAh g−1 (160.4 F g−1), the considerable specific energy of 50.125 Wh kg−1 at a specific power of 750.04 W kg−1 and outstanding robustness of 96.8 %. [ABSTRACT FROM AUTHOR]

Herein, electromembrane extraction was combined with ultraviolet spectrophotometry using a customized manifold for preconcentration and simultaneous determination of morphine, codeine, and papaverine in water and human urine samples. Absorption spectra of the extracts were recorded inside the lumen of the hollow fiber using two fiber optics connected to a miniature spectrophotometer. Partial least squares regression was applied to resolve the overlapped spectra of the analytes. Performance of the model was validated by an independent test set. Central composite design was applied to optimize the extraction parameters. The optimized extraction conditions are as follows; supporting liquid membrane: 2‐nitrophenyl octyl ether containing 15% v/v bis(2‐ethylhexyl) phosphate, applied voltage: 80 V, donor pH: 3.0, acceptor pH: 1.0, extraction time: 20 min. Finally, the optimized extraction method was validated for determination of the mentioned alkaloids in human urine samples. The method showed good linearity (R2 > 0.995) for all of the mentioned alkaloids. The limits of detection for morphine, codeine, and papaverine in diluted human urine were found to be 0.6, 1.1, and 0.6 ng/mL, respectively with acceptable relative standard deviations. Enrichment factors of 104, 108, and 102 were achieved for morphine, codeine, and papaverine, respectively. [ABSTRACT FROM AUTHOR]

In this study, a platinum wire coated with poly(3,4-ethylenedioxythiophen) was used as an electro-assisted solid-phase microextraction fiber for the quantification of tricyclic antidepressant drugs in biological samples by coupling to GC employing a flame ionization detector. In this study, an electric field increased the extraction rate and recovery. The fiber used as a solid phase was synthesized by the electropolymerization of 3,4-ethylenedioxythiophen monomers onto a platinum wire. The ability of this fiber to extract imipramine, desipramine, and clomipramine by using the electro-assisted solid-phase microextraction technique was evaluated. The effect of various parameters that influence the extraction efficiency, which include solution temperature, extraction time, stirring rate, ionic strength, time and temperature of desorption, and thickness of the fiber, was optimized. Under optimized conditions, the linear ranges and regression coefficients of calibration curves were in the range of 0.5-250 and 0.990-0.998 ng/mL, respectively. Detection limits were in the range of 0.15-0.45 ng/mL. Finally, this method was applied to the determination of drugs in urine and wastewater samples and recoveries were 4.8-108.9%. [ABSTRACT FROM AUTHOR]