Redox-active pyrrole (Py) monomers were intercalated into 1D nanochannels of [Cd(NDC)0.5(PCA)]·Gx (H2NDC = 2,6-napthalenedicarboxylic acid, HPCA = 4-pyridinecarboxylic acid, G = guest molecules) (1) - a fluorescent 3D MOF (λem = 385 nm). Subsequent activation of 1⊃Py upon immersing into iodine (I2) solution resulted in an increment of the bulk electrical conductivity by ∼9 orders of magnitude. The unusual increase in conductivity was attributed to the formation of highly oriented and conducting polypyrrole (PPy) chains inside 1D nanochannels and specific host-guest interaction in 1⊃PPy thereof. The Hall-effect measurements suggested 1⊃PPy to be an n-type semiconductor material with remarkably high-carrier density (η) of ∼1.5 × 10(17) cm(-3) and mobility (μ) of ∼8.15 cm(2) V(-1) s(-1). The fluorescence property of 1 was almost retained in 1⊃PPy with concomitant exciplex-type emission at higher wavelength (λem = 520 nm). The here-presented results on [MOF⊃Conducting Polymer] systems in general will serve as a prototype experiment toward rational design for the development of highly conductive yet fluorescent MOF-based materials for various optoelectronic applications.
An excited-state intramolecular proton transfer (ESIPT) mechanism based two reactive probes HBTCo and HBTCu is reported for the selective detection of Co(2+) and Cu(+) respectively in a reducing aqueous environment. Co(2+) and Cu(+) mediated oxidative benzylic ether (C-O) bond cleavage offers ratiometric detection of these metal ions.
Commercial supercapacitors, mainly made of activated carbon, offers insufficient capacitance at high cost. Recently, graphene-based materials are emerging as smart alternatives. Reduction of graphene oxide (GO) is an elegant and important approach to produce reduced graphene oxide (rGO), because it holds the promise to closely resemble its physicochemical properties with pristine graphene. The conventional reducing agents such as sodium borohydride and hydrazine are strong reducing agents, and cannot be recycled. The fast reaction kinetics bring an imbalance in the desirable properties of rGO. Here, we present onepot chemical reduction of GO in aqueous medium by an unconventional mild reducing agent (FeCl2/HCl) where pure rGO is isolated and the reducing agent is recycled upon simple treatment of the filtrate with HCl. The fabricated all-solid-state supercapacitor of assynthesized rGO exhibited significantly higher specific capacitance (171 F/g at 1.1 A/g), remarkable cycling stability (>80% retention of capacitance beyond 100,000 continued cycles), and flexibility (>500 bending cycles), which is comparatively better than those of rGO derived from conventional reducing agents. Use of commercially available organic electrolyte further boosted the supercapacitor performance (282 F/g at 1.8 A/g) of rGO. 1
A triple-action π-conjugated polymer chemosensor is developed for sensing temperature, selective detection of copper(ii) metal-ion and biological species - amino acids, in two wavelength optical switches based on red-fluorescent and blue-fluorescent molecular probes.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.