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All-inorganic cesium lead halide perovskites (CsPbX 3 , X = Cl, Br, and I) have attracted considerable attention with superior electrical and photophysical properties. In this study, luminescent perovskite (CsPbBr 3 ) quantum dots (QDs) as sensing elements combined with molecularly imprinted polymers (MIPs) are used for the detection of omethoate (OMT). The new MIPs@CsPbBr 3 QDs were synthesized successfully through the imprinting technology with a sol− gel reaction. The fluorescence (FL) of the MIPs@CsPbBr 3 QDs was quenched obviously on loading the MIPs with OMT, the linear range of OMT was from 50 to 400 ng/mL, and the detection limit was 18.8 ng/mL. The imprinting factor was 3.2, which indicated excellent specificity of the MIPs for the inorganic metal halide (IMH) perovskites. The novel composite possesses the outstanding FL capability of CsPbBr 3 QDs and the high selectivity of molecular imprinting technology, which can convert the specific interactions between template and the imprinted cavities to apparent changes in the FL intensity. Hence, a selective and simple FL sensor for direct and fast detection of organophosphorus pesticide in vegetable and soil samples was developed here. The present work also illustrates the potential of IMH perovskites for sensor applications in biological and environmental detection.

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Development of a highly efficient material with large specific area was scientifically and technologically important for simultaneous elimination of inorganic and organic pollutants from wastewater. In this work, layered-double-hydroxides-coated (LDHs-coated) hollow carbon microsphere composites (HCMSs; LDHs/HCMSs) were fabricated using carbon spheres as templates via a hydrothermal method and were then applied for mutual removal of Pb­(II) and humic acid (HA) under various experimental conditions, i.e., pH, ionic strength, contact time, addition sequences, and coexisting ions. The results indicated that the copresence of Pb­(II) and HA facilitated single target pollutant [Pb­(II) or HA] adsorption at pH < 8.0. The adsorbed HA was responsible for the improvement of Pb­(II) adsorption, primarily as a result of the formation of HA-Pb-LDHs/HCMSs ternary complexes. Competitive adsorption of Cu­(II), Co­(II), Pb­(II), and Ni­(II) ions on LDHs/HCMSs was also investigated, and the LDHs/HCMSs had the affinity in the order of Co­(II) < Ni­(II) < Cu­(II) < Pb­(II). Interestingly, in binary/quaternary systems, the results showed that the presence of Cu­(II), Co­(II), and Ni­(II) ions exhibited slight inhibition on Pb­(II) adsorption. However, the total amounts of heavy metal ions adsorbed on LDHs/HCMSs increased with the increase of the heavy metal ions. Results of X-ray photoelectron spectroscopy and Fourier transformed infrared spectroscopy indicated that outer-sphere surface complexation mainly dominated the adsorption of Pb­(II) on LDHs/HCMSs, while the adsorption of HA was attributed to surface complexation of the disassociated HA on LDHs/HCMSs. The findings highlighted the novel synthesis of LDHs/HCMSs and its potential application for simultaneous removal of different metal ions and natural organic contaminants from wastewater in environmental pollution cleanup.

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