Oxygen vacancy and valence engineering in CeO₂ through distinct sized ion doping and their impact on oxygen reduction reaction catalysis

Abstract

Defect tuning in ceria to enhance its catalytic properties is a subject of great interest for scientific community owing to the growing demand for catalytic materials in drug, automobile and...

Ample Lewis Acidic Sites in Mg2B2O5 Facilitate N2 Electroreduction through Bonding–Antibonding Interactions

“…The three positron lifetimes and intensities, along with the fitting of the spectrum, are shown in Figure a. As can be seen from the figure, the principal lifetime from the spectrum is of 218 ps and is attributable to positron annihilation from the delocalized states in Mg 2 B 2 O 5 with contribution from shallow positron traps like oxygen vacancies . The planar BO 3 is expected to offer more space for positron delocalization, enhancing the positron lifetime.…”

“…As can be seen from the figure, the principal lifetime from the spectrum is of 218 ps and is attributable to positron annihilation from the delocalized states in Mg 2 B 2 O 5 with contribution from shallow positron traps like oxygen vacancies. 39 The planar BO 3 is expected to offer more space for positron delocalization, enhancing the positron lifetime. An enhanced positron lifetime in turn foretells that the electron−positron annihilation or recombination rate is low, suggesting a free electron cloud density, over the planar BO 3 unit wherein the B and O centers can take part in the bonding−anti bonding interactions with the N 2 molecules prior to NRR as schematically shown in Figure 3b.…”

Rare earth oxide based electrocatalysts: synthesis, properties and applications

“…10b). 196 Zou et al also prepared highly active and durable RE metal oxide/ oxygen sulfide (Ce 2 O 2 S/CeO 2 )/N, S double doped carbon (Ce species/NSC) catalysts with good oxygen storage/release ability at different temperatures (800-1000 1C) to improve ORR efficiency. 197 Porous Ce 2 O 2 S/NSC (950 1C) catalyst, as an air breathing catalyst, has a maximum power density of 1087.2 mW m À2 , which is higher than the power density of other Ce/NSCs and commercial Pt/C (989.13 mW m À2 ) in microbial fuel cells.…”

Research progress of metal oxide supports for fuel cells electrocatalysts

“…This is due to the Pt-exposed (111) crystal facets and oxygen vacancy-mediated alloying of interfacial PtCe, which promotes the adsorption and dissociation of O 2 and the desorption of OHad, thus exhibiting excellent ORR electrocatalytic performance. Das [61] investigated the doping of CeO 2 with different trivalent rare earth ions (Y 3 + , Eu 3 + and La 3 + ). The La 3 + doped samples showed higher Ov concentration compared to the Y 3 + /Eu 3 + doped CeO 2 as measured by positron annihilation lifetime spectroscopy (PALS).…”