Influence of the nature of the lanthanide element of Ln2CuO4 precursors on the catalytic activity obtained after activation in the CO + NO reaction

Influence of Adsorption and Catalytic Reaction on Sensing Properties of a Potentiometric La[sub 2]CuO[sub 4]∕YSZ∕Pt Sensor

“…12,13 La 2 CuO 4 is catalytically active for NO reduction by CO as a three-way catalyst but has limited catalytic selectivity in the presence of O 2 . [14][15][16][17] The catalytic activity of La 2 CuO 4 has been attributed to its small bandgap and oxygen defects in the lattice. 18 As we have previously described in our proposed potentiometric sensor mechanism "differential electrode equilibria", the semiconducting behavior of the electrodes also contributes to the potentiometric response.…”

Reduction and catalytic behaviour of heterobimetallic copper–lanthanide oxides

“…Nevertheless, both techniques clearly show that the copper species present in the heterobimetallic copper-lanthanide oxides have different reducibilities that can be ascribed to each mass loss. Moreover, the fact that the T m values for the reduction of copper-lanthanide heterobimetallic CuO species are higher than that of pure CuO [33][34][35], instead of lower [36,37], can be attributed to a form of stable copper oxide (oxygen less labile) more difficult to reduce than pure CuO and due to interaction with the lanthanide containing phases (Ln 2 CuO 4 or CeO 2 ). Gervasini and co-workers [34] proposed the same explanation for the hindered reduction of nano-sized CuO dispersed on synthesized silica modified with alumina, titania and zirconia.…”

“…To the best of our knowledge, H 2 -TPR of lanthanide cuprates was only reported by Perrichon and co-workers [35] who studied the reduction of Ln 2 CuO 4 (Ln = La, Pr, Nd). Two main reduction peaks were observed at 420/495, 540/625, and 600/650 • C for In our study, only one broad main reduction peak was observed for the reduction of the Ln 2 CuO 4 phase.…”

“…In contrast, in this study the T m is essentially the same when Pr or Nd substitutes La, within the T m experimental error (±5 • C). This difference can be attributed to the presence of Cu 0 formed during the first reduction step in the Ln 2 CuO 4 lattice that through a faster dissociation of H 2 promotes the reduction of the host oxide at lower temperatures [33,35,[43][44][45][46]. As an example, the insertion of copper in ceria lattice promotes the reduction of the host oxide that occurs in the range 525-625 • C vs. 625-775 • C for pure CeO 2 through an easier dissociation of H 2 on the metallic copper formed [45,46].…”