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Nerve agents are highly toxic compounds that are based on organophosphorus chemistry, and their use is banned by international treaties regarding chemical weapons. Among the various nerve agents, sarin is highly lethal and inhibits the neuronal transmission and signaling of acetylcholinesterase. This study reports a fluorescent probe, ( E )-3-(((2-(1 H -benzo[ d ]imidazole-2-yl)phenyl)imino)methyl)-2-methoxy-2 H -chromen-4-ol (BPMC), that demonstrates exceptional efficiency in detecting diethylchlorophosphate (DCP), a sarin surrogate, in solution and vapor phases. The gradual addition of DCP to the probe solution leads to a turn-on photoluminescence transition from blue to cyan because of the extension of intramolecular charge transfer transition (ICT) and inhibition of the excited-state intramolecular proton transfer (ESIPT) process. The minimum levels of DCP for detection and quantification were determined to be 6.6 μM and 22 μM, respectively, in the presence of various analogous analytes. Additionally, a test kit made of strips of cellulose paper was successfully assembled for real-time application. Dip-stick and dip-vial-conical-flask analyses were demonstrated as effective tools for detecting and quantifying DCP in the vapor phase. Furthermore, a smartphone-based approach was executed for the practical application of BPMC, enabling immediate identification and quantification of DCP in actual danger scenarios. Thus, this work presents a new ratiometric fluorogenic probe for the detection of sarin surrogate with potential application in actual hazardous situations.

The high-level toxic effects of organophosphate (OP) nerve agents severely threaten national security and public health. Generating trustworthy, accurate methods for quickly identifying these poisonous chemicals is urgently necessary. In this study, we have presented an azine-based colorimetric sensor (HBD) for the highly sensitive and selective identification of poisonous sarin gas surrogate diethylchlorophosphate (DCP). Our introduced sensor shows a purple color in contact with DCP, which is fully reversible upon the addition of triethylamine (TEA). The detection limit of our sensor for the toxic nerve agent mimic DCP is in the μM range. We have fabricated a test kit to verify the capability of HBD for on-the-spot identification of DCP to execute its practical use. To prove that HBD is an effective chemosensor, dip-stick investigation was conducted to detect DCP in the vaporous stage in the presence of different OPs, inorganic phosphates (IPs), and many other deadly analytes. A cellphone-based display method was also undertaken for on-the-spot recognition and measurement of DCP in isolated regions.

In this study, an excellent chromo-fluorogenic PMPA probe, ( E )-4-(((4-(benzoxazole-2-yl)phenyl)imino)methyl)- N , N -diphenylamine, is introduced for the detection of sarin gas mimic diethyl chlorophosphate (DCP) in solution and gaseous phases. On adding DCP into PMPA solution in a pure DMSO and water-DMSO (4 : 1) medium, it exhibits a hypsochromic shift from yellow to colorless and from no fluorescence to highly intense blue-violet photoluminescence via the formation of a phosphorylated PMPA-DCP product due to the inhibition of intramolecular charge transfer (ICT) and photoinduced electron transfer (PET) mechanism. The sensor could detect DCP in the presence of several other notorious guest analytes with a detection limit in the μM range. Moreover, to accomplish the on-spot detection of DCP and explore the practical applicability of the probe, a paper strip-based test kit, "dip-stick" method, and, more interestingly, a real sample analysis was demonstrated in spiked soil samples.

Herein, we report vanadium carbide (V8C7) nanowires (NWs) axially grown on carbon cloths (CCs) as a dual-ion accepting cathode for both lithium (LIBs) and sodium-ion batteries (SIBs). Using a facile hydrothermal method, we grew V2O3 NWs on CCs and subsequently reduced them to V8C7 by annealing with carbon sources under a H2/Ar atmosphere. In striking contrast to V2O5 NW cathodes obtained by annealing under air, the V8C7 NWs exhibit outstanding cycling stability during 500 cycles, and good rate capability for both LIBs and SIBs. V8C7 NWs as cathode active materials for LIBs exhibited 203.9 mA h g-1 specific capacity at 0.1 C after 500 cycles, 91.12% cycling retention and a coulombic efficiency of 99.84%. As cathodes in SIBs, the V8C7 NWs delivered 176.34 mA h g-1 specific capacity at 0.1 C during 300 cycles. Their defect sites by removal of the oxygen framework in V2O3 NWs have a high surface area (183.27 m2 g-1) and the unique 1D NW structure highly mitigates the volume changes during charge and discharge showing a superior electrochemical performance. Compared to commercially available cathodes, V8C7 nanowires have very good cycling stability and enhanced electrical conductivity. Moreover, the synergistic effect with 3D CCs utilized here as a current collector provides a large number of cation-accessible active sites in conjunction with high electrical conductivity and chemical stability.

Functionalized polymer membrane electrodes based multichannel sensor is used as an electronic tongue to monitor the drinking water (DW) quality simply by measuring the surface electric potential with respect to Ag/AgCl reference electrode in 1 mM aqueous KCl. Changes of minute concentration of dissolved minerals greatly affected the surface potential of the sensor. The three-channel sensor device (electronic tongue) is made by using three different functionalized polymer membrane electrodes, namely, phosphorylated hexadecyl trimethyl ammonium chloride modified polyvinyl alcohol-polyacrylic acid membrane; phosphorylated and crosslinked polyvinyl- co -ethylene membrane; phosphorylated and crosslinked polyvinyl alcohol membrane, as working electrodes and a Ag/AgCl reference electrode. Developed electronic tongue is utilized for the sensing measurements of five different branded drinking water samples. Sensor characteristics, like, temporal stability, response stability, response patterns and repeatability of responses have been studied. Principal component analysis of the sensing data shows good discrimination among the analytes under study. Distinctive response patterns were observed for different drinking water samples in variation with the concentrations of dissolved minerals. Surprisingly sensor has done great job in order to monitor the dissolved minerals as present in tested samples with the help of standard calibrated sensing data.