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The adsorption of CO2using layered double hydroxides (LDHs) such as Mg-Al LDH is both technically feasible and economical. Although some approaches to the modification of LDHs have proved fruitful, there is still a need for further improvement in the adsorption capacity of modified LDHs. Here, a new optimization direction for amino-modified Mg-Al-LDHs is proposed based on using DFT and AIMD simulations to elucidate the mechanism of CO2diffusion. The proposed approach was then evaluated experimentally. Theoretical calculations showed that the adsorption energy of ordinary amino-modified LDHs was low, at − 0.56 eV. DFT simulations showed that the number of interlayer water molecules affects the CO2adsorption energy, with the optimum adsorption energy of − 0.78 eV obtained in the presence one interlayer water molecule. Experimental analysis showed that the drying time affects the amount of interlayer water and thus the CO2adsorption capacity, with the maximum adsorption capacity of 1.7424 mmol/g obtained after drying for 5 h. This study provides useful insights towards the development of materials such as Mg-Al LDHs for efficient CO2adsorption and highlights the critical role of interlayer-bound water on the adsorption performance.

A new technique based on laser vitrification of cordierite ceramic powders is used to fabricate arbitrarily shaped microlens arrays on a glass substrate. Crack-free semispherical and quasi-spherical lenses with good optical and surface quality are demonstrated.