This proof-of-concept study proposes a novel sensing mechanism for selective and label-free detection of 2,4,6-trinitrotoluene (TNT). It is realized by surface chemistry functionalization of silica nanoparticles (NPs) with 3-aminopropyl-triethoxysilane (APTES). The primary amine anchored to the surface of the silica nanoparticles (SiO2-NH2) acts as a capturing probe for TNT target binding to form Meisenheimer amine-TNT complexes. A colorimetric change of the self-assembled (SAM) NP samples from the initial green of a SiO2-NH2 nanoparticle film towards red was observed after successful attachment of TNT, which was confirmed as a result of the increased separation between the nanoparticles. The shift in the peak wavelength of the reflected light normal to the film surface and the associated change of the peak width were measured, and a merit function taking into account their combined effect was proposed for the detection of TNT concentrations from 10-12 to 10-4 molar. The selectivity of our sensing approach is confirmed by using TNT-bound nanoparticles incubated in AptamerX, with 2,4-dinitrotoluene (DNT) and toluene used as control and baseline, respectively. Our results show the repeatable systematic color change with the TNT concentration and the possibility to develop a robust, easy-to-use, and low-cost TNT detection method for performing a sensitive, reliable, and semi-quantitative detection in a wide detection range.
Stable solid electrolytes are essential for advancing the safety and energy density of lithium batteries, especially in high-voltage applications. In this study, we designed an innovative high-entropy chloride solid electrolyte (HE-5, Li2.2In0.2Sc0.2Zr0.2Hf0.2Ta0.2Cl6), using multielement doping to optimize both ionic conductivity and high-voltage stability. The high-entropy disordered lattice structure facilitates lithium-ion mobility, achieving an ionic conductivity of 4.69 mS cm-1 at 30 °C and an activation energy of 0.300 eV. Integration of HE-5 into all-solid-state batteries (ASSBs) with NCM83 cathodes and a Li-In anode enables outstanding electrochemical performance, sustaining 70% capacity retention over 1600 cycles at a 4 C rate. Moreover, the high configurational entropy stabilizes the electrolyte's structure at elevated voltages, enabling stable operation at 5.0 V without significant degradation. Our work presents the dual advantages of high-entropy engineering in boosting high ionic conductivity and voltage stability, providing a broad roadmap for next-generation energy-dense ASSBs.