@article {48292,
	title = {Oxidation of ethylene by Cu/TiO2: reducibility of Cu2+ in TiO2 as a possible descriptor of catalytic efficiency},
	journal = {Catalysis Science \& Technology},
	volume = {13},
	year = {2023},
	month = {APR},
	pages = {2330-2339},
	type = {Article},
	abstract = {<p>
	Catalytic oxidation using non-noble metal-based catalysts is a promising approach to mitigate pollution due to VOCs in the air. In this work, mesoporous Cu/TiO2 catalysts containing different concentrations of Cu2+ (0.2, 1, 3, and 4 wt\% Cu w.r.t. Ti) were synthesized using the sol-gel technique. The catalysts were characterized using inductively coupled plasma-optical emission spectrometry, XRD, Raman spectroscopy, N-2 physisorption, cyclic voltammetry, H-2-TPR and electron microscopy to understand the structure and composition. The thermal catalytic gas phase oxidation of ethylene was studied by heating a mixture of ethylene (1.5 vol\%) and air (5.9 vol\%) in the presence of the Cu/TiO2 samples in the temperature range of 298 to 773 K. Cu/TiO2 showed a higher catalytic activity compared to TiO2 for the thermal oxidation of ethylene, indicating a strong promotion by doped copper ions. A volcanic behaviour in the catalytic activity was observed with different concentrations of Cu doping, with 1\% Cu/TiO2 showing a 99.5\% ethylene conversion at 673 K and 100\% selectivity to CO2. The activity of 1\% Cu/TiO2 remained consistent without deactivation for 24 h. At low dopant concentrations of Cu (0.2 and 1\% Cu/TiO2), the reduction of Cu2+ to Cu+ was observed. An interplay of oxygen vacancies (O-V), Cu+, Cu2+ and Ti4+ may be involved in controlling the activity. DRIFT studies indicated the formation of surface bidendate carbonate as a possible intermediate.</p>
},
	issn = {2044-4753},
	doi = {10.1039/d2cy02170f},
	author = {Rajendran, K. and Sharma, Mandeep and Jaison, Augustine and Ankitha, Menon and Tiwari, Ankit D. and Vinod, C. P. and Jagadeesan, Dinesh}
}
