Atomically dispersed nickel as coke-resistant active sites for methane dry reforming

Dry reforming of methane (DRM) is an attractive route to utilize CO2 as a chemical feedstock with which to convert CH4 into valuable syngas and simultaneously mitigate both greenhouse gases. Ni-based DRM catalysts are promising due to their high activity and low cost, but suffer from poor stability due to coke formation which has hindered their commercialization. Herein, we report that atomically dispersed Ni single atoms, stabilized by interaction with Ce-doped hydroxyapatite, are highly active and coke-resistant catalytic sites for DRM. Experimental and computational studies reveal that isolated Ni atoms are intrinsically coke-resistant due to their unique ability to only activate the first C-H bond in CH4, thus avoiding methane deep decomposition into carbon. This discovery offers new opportunities to develop large-scale DRM processes using earth abundant catalysts

Calcium deficiency in hydroxyapatite and its drug delivery applications

In this work, calcium deficient hydroxyapatites (HAPs) [Ca 10 ? x (PO 4 ) 6 (OH) 2 ] [where x = 0 ? 0.3] were synthesised by precipitation method and calcined samples were characterised by Fourier transformation infrared spectroscopy, powder X-ray diffraction, scanning electron microscopy and energy-dispersive X-ray spectroscopy techniques to check phase purity, calcium deficiency, particle size and shape. The results indicate that the structure of the HAP can tolerate a calcium deficiency up to 0.2. The calcium deficient HAP (x = 0.1) powder was found to be highly porous with a particle size below 200 nm. This powder was used as a drug delivery carrier for the drug, ciprofloxacin and sustained release of the drug in the phosphate buffer solution was investigated