Characterization of copper/zirconia catalysts prepared by an impregnation method

Copper oxide as efficient catalyst for oxidative dehydrogenation of alcohols with air

“…The low temperature peaks of TPR due to highly dispersed CuO and/or Cu(II) species have also been observed for supported CuO. 44,45 Van der Grift et al 46 and Robertson et al 47 further supported this observation concluding that the highly dispersed copper oxide species are more easily reduced than bulk CuO. CAPS-CuO seemed to have no bulk copper oxide and was therefore reduced at very low temperatures, while com-CuO comprises both dispersed and bulk-like CuO resulting in a shift in reduction peak to higher temperatures without exhibiting true bulk behavior.…”

HRTEM observation of the monoclinic-to-tetragonal m-t) phase transition in nanocrystalline ZrO2

“…Monoclinic-to-tetragonal phase transitions within unconstrained nanoparticles of ZrO 2 . The relations 1and 3 occur most frequently; the relations 2 and 4 were found only in combination with 1and 3 in the "core-shell" structures.…”

“…Some investigations have recently been done on catalysts containing both copper and ZrO 2 (zirconia) with respect to the above reactions. In this context, the zirconia may be used either as a stabilizing additive to the Cu/ZnO(/Al 2 O 3 ) catalysts [1], or as an alternative support replacing for example, ZnO [2]. Zirconia modified with anions such as sulphate is an acid catalyst and became known for its extraordinary activity in low-temperature alkane isomerization [3]; it is also active for a number of other acid-catalysed reactions [4].…”

TPR, ESR, and XPS Study of Cu2+Ions in Sol–Gel-Derived TiO2

“…These results showed a weight loss from room temperature up to approximately 600 K together with an endothermic peak (about 360 K) and an asymmetric exothermic peak (about 525 K). The former was assigned to the loss of 2-propanol and water (22) and to the decomposition of amine copper complexes (23). The exothermic peak, whose relative intensity depends on the copper content, was due to the decomposition of acetate groups, which is strongly exothermic (24).…”