4 research outputs found
Long-term survival following radiotherapy and cytarabine chemotherapy for sporadic primary central nervous system lymphoma
Tuning Chemical and Morphological Properties of Ceria Nanopowders by Mechanochemistry
Cerium oxide powders are widely used and are of fundamental
importance
in catalytic pollution control and energy production due to the unique
chemical properties of CeO2. Processing steps involved
in catalyst preparation, such as high-temperature calcination or mechanical
milling processes, can alter the morphological and chemical properties
of ceria, heavily affecting its final properties. Here, we focus on
the tuning of CeO2 nanopowder properties by mild- and high-energy
milling processes, as the mechanochemical synthesis is gaining increasing
attention as a green synthesis method for catalyst production. The
textural and redox properties were analyzed by an array of techniques
to follow the aggregation and comminution mechanisms induced by mechanical
stresses, which are more prominent under high-energy conditions but
strongly depend on the starting properties of the ceria powders. Simultaneously,
the evolution of surface defects and chemical properties was followed
by Raman spectroscopy and H2 reduction tests, ultimately
revealing a trade-off effect between structural and redox properties
induced by the mechanochemical action. The mild-energy process appears
to induce the largest enhancement in surface properties while maintaining
bulk properties of the starting materials, hence confirming its effectiveness
for its exploitation in catalysis