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In this study, new luminescent coordination polymers containing cadmium ions, 1,10-phenanthroline and benzene-1,3,5-tricarboxylic acid ligands were synthesised under hydrothermal conditions. The structure of the synthesised Cd(II) CPs was investigated by X-ray diffraction, scanning electron microscope, matrix-assisted laser desorption ionisation mass spectrometry, elemental analysis, thermogravimetric analysis and Fourier transform infrared spectroscopy. In addition, the adsorption and sensing applications of Cd(II) CPs were investigated. The removal of diclofenac, an organic micropollutant, from aqueous systems was investigated for the adsorption application of Cd(II) CPs. The adsorption isotherms fitted the Langmuir model better than the Freundlich model. Adsorption equilibrium was reached after 240 min at pH 6.5 and 298 K, resulting in a maximum adsorption capacity of 1822 mg/g. In the other analytical application of Cd(II) CPs, the detection of Cu2+ and Ni2+ cations in aqueous medium was investigated based on their fluorescence properties. According to the results Cd(II) CPs have better sensitivity and selectivity. The fluorescence intensity of Cd(II) CPs decreased linearly due to the quenching mechanism. The K SV values were calculated to be 1.82 × 108 M−1 for Cu2+ and 8.2 × 108 M−1 for Ni2+. The limits of detection Cu2+ and Ni2+ cations for Cd(II) CPs were calculated to be 2.78 × 10−8 and 6.15 × 10−9 M, respectively. The detection of Cu2+ and Ni2+ ions was performed with a fast response, a wide linear range and a very low detection limit and could be used on real water samples without any matrix interference. [Display omitted] • Cd(II) CPs were hydrothermally synthesized with a mixed ligand. • Cd(II) CPs have used removal of diclofenac and detection of Cu2+ and Ni2+. [ABSTRACT FROM AUTHOR]

Commercial micro‐mesoporous carbonaceous material (MCM; 56.8% mesopores) was applied for investigating the removal phenomenon of naproxen drug in aqueous solutions through batch adsorption experiments. Results demonstrated that the adsorption capacity of MCM to naproxen was slightly affected by different pHeq (2.0–11) and ionic strength (0–1 M NaCl). Adsorption kinetics, isotherms, thermodynamics, and mechanisms were evaluated at pH 7.0. Adsorption kinetics indicated the rate constants for adsorption (0.2 × 10−3 L/(mg × min) and desorption (0.076/min) and the adsorption equilibrium constant (2.6 × 10−3 L/mg). Adsorption isotherm showed that MCM exhibited a high‐affinity adsorption capacity to naproxen (even at low concentrations) and its Langmuir maximum adsorption capacity (Qmax) was 252.7 mg/g at 25°C. Adsorption thermodynamics proved that the adsorption process was endothermic and physisorption (ΔH° = 9.66 kJ/mol). The analysis result of pore size distribution demonstrated that the internal pore structure of MCM was appropriate for adsorbing naproxen molecules. Pore‐filing mechanism (pore diffusion phenomenon) was confirmed by a considerable decrease in BET‐surface area (585 m2/g) and total pore volume (0.417 cm3/g) of MCM after adsorbing naproxen (~1000 mg/L and pH 7.0) at 5 min (341 and 0.256), 60 min (191 and 0.205), 120 min (183 and 0.193), 360 min (144 and 0.175), and 24 h (71.6 m2/g and 0.123 cm3/g, respectively). The pore diffusion occurred rapidly (even at the initial adsorption period of 5 min). The FTIR technique was applied to identify the existence of C–H···π and n–π interaction. π–π interaction (evaluated through ID/IG ratio and C=C band) played a minor contribution in adsorption mechanisms. The ID/IG ratio (determined by the Raman technique) of MCM before adsorption (1.195) was similar to that after adsorption (1.190), and the wavenumber (C=C band; its FTIR spectrum) slightly shifted from 1638 to 1634 cm−1 after adsorption. A decrease in the Qmax value of MCM from 249 to 217 (H2O2‐oxidized MCM) or to 224 mg/g (HNO3‐oxidized MCM) confirmed the presence of π–π interaction. Electrostatic attraction was a minor contribution. MCM can serve as a promising material for removing naproxen from water environment through a pore‐filling mechanism. Practitioner Points: Pore‐filling mechanism was proposed by comparing textural properties of MCM before and after adsorbing naproxen.C–H···π and n–π interactions were identified via FTIR technique.π–π interaction was observed by FTIR and Raman techniques.Oxidation of MCM with HNO3 or H2O2 was a helpful method to explore π–π interaction.Electrostatic attraction was explained through studies: effects of pH and NaCl along with desorption. [ABSTRACT FROM AUTHOR]