01854nas a2200157   4500008004100000245010600041210006900147260000800216300001600224490000600240520125700246100001801503700002301521700003001544856012201574       2016                        eng d00aC-H activation of methane to formaldehyde on Ce1-xZrxO2 thin films: a step to bridge the material gap0 aCH activation of methane to formaldehyde on Ce1xZrxO2 thin films  cDEC  a3650–36560 v83 a<p>Ce1−xZrxO2 (CZ) thin films were prepared by a combination of sol–gel and spin-coating methods and were evaluated for the C−H activation of methane by using a molecular beam set-up with the aim to bridge the material gap. The C−H activation of methane begins at 950 K, and a Ce-rich CZ composition displays a high selectivity (4–12 %) to the partially oxidised product, formaldehyde. A 10–12 % selectivity towards HCHO with 1.6 % methane conversion was observed with methane-rich CH4/O2 reactant compositions at 1050 K. Short contact times, prevalent under molecular beam conditions, could be a possible reason for HCHO formation. Although combustion products were observed instantly upon shining the mixture of reactants on CZ surfaces, up to 20 s delay was observed before formaldehyde generation, which indicates that the oxygen vacancy migration contributes to the rate-determining step and the diffusion-controlled nature of the reaction. A burst in HCHO generation at the point of molecular beam opening, after beam-closed conditions, suggests that the diffusion of oxygen vacancies to the surface is the reason for HCHO formation. Kinetics results also indicate the necessity of reduction sites for HCHO generation.</p>1 aDubey, Anjani1 aKolekar, Sadhu, K.1 aGopinath, Chinnakonda, S.  uhttps://library.ncl.res.in/content/c-h-activation-methane-formaldehyde-ce1-xzrxo2-thin-films-step-bridge-material-gap