Magnesium-doped ZnO (ZMO) nanoparticles were synthesized through an oxalate coprecipitation method. Crystallization of ZMO upon thermal decomposition of the oxalate precursors was investigated using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) techniques. XRD studies point toward a significant c-axis compression and reduced crystallite sizes for ZMO samples in contrast to undoped ZnO, which was further confirmed by HRSEM studies. X-ray photoelectron spectroscopy (XPS), UV/vis spectroscopy and photoluminescence (PL) spectroscopy were employed to establish the electronic and optical properties of these nanoparticles. (XPS) studies confirmed the substitution of Zn(2+) by Mg(2+), crystallization of MgO secondary phase, and increased Zn-O bond strengths in Mg-doped ZnO samples. Textural properties of these ZMO samples obtained at various calcination temperatures were superior in comparison to the undoped ZnO. In addition to this, ZMO samples exhibited a blue-shift in the near band edge photoluminescence (PL) emission, decrease of PL intensities and superior sunlight-induced photocatalytic decomposition of methylene blue in contrast to undoped ZnO. The most active photocatalyst 0.1-MgZnO obtained after calcination at 600 °C showed a 2-fold increase in photocatalytic activity compared to the undoped ZnO. Band gap widening, superior textural properties and efficient electron-hole separation were identified as the factors responsible for the enhanced sunlight-driven photocatalytic activities of Mg-doped ZnO nanoparticles.

An approach employing a dual-porous metal organic framework as a catalyst for room temperature CO2 fixation via cyclic carbonate synthesis with high selectivity towards cyclic carbonates under solvent free conditions was demonstrated.

A water stable zinc-MOF (ZnGlu) catalyst was facilely prepared from the proteinogenic amino acid, l-glutamic acid at room temperature in aqueous medium. CO2 fixations were promoted by the ZnGlu catalyst's inherently coordinated water and externally added water in yielding cyclic carbonate and cyclic urethane at room temperature. This eliminates the need for catalyst activation, making ZnGlu a ready-to-use catalyst. The enhanced CO2 cycloaddition with added water hints at the application of ZnGlu in wet flue gas conversions. This is the first reported attempt for the use of an MOF in the cycloaddition of aziridine and CO2.

A dual-porous, three-dimensional, metal-organic framework [ZnO(2,6-NDC)(BTB)] (MOF-205, BET = 4200 m/g) has been synthesized using microwave power as an alternative energy source for the first time, and its catalytic activity has been exploited for CO-epoxide coupling reactions to produce five-membered cyclic carbonates under solvent-free conditions. Microwave synthesis was performed at different time intervals to reveal the formation of the crystals. Significant conversion of various epoxides was obtained at room temperature, with excellent selectivity toward the desired five-membered cyclic carbonates. The importance of the dual porosity and the synergistic effect of quaternary ammonium salts on efficiently catalyzed CO conversion were investigated using various experimental and physicochemical characterization techniques, and the results were compared with those of the solvothermally synthesized MOF-205 sample. On the basis of literature and experimental inferences, a rationalized mechanism mediated by the zinc center of MOF-205 for the CO-epoxide cycloaddition reaction has been proposed.

Covalent post functionalized ZIF-90 with pyridinium based ionic liquid was prepared and used as catalyst for the solventless synthesis of propylene carbonate.