To explore a new class of material (X-type hexaferrites) for N₂O decomposition

Abstract

Nitrous oxide serves as a green propellant for space applications; however, an active and stable catalyst is required for its decomposition. A new class of material (X-type hexaferrites) was tested for this reaction for the first time. The catalysts were prepared by a co-precipitation method and a pure single hexagonal phase was confirmed by XRD and SEM. The developed pure and doped catalysts were found to be catalytically active for nitrous oxide decomposition reaction and the activity increased with increasing dopant content.However, Cr-Mn co-doped materials showed higher catalytic activity than Mn-doped samples. The cationic substitution and surface defects (oxygen vacancies) were found to be responsible for the upsurge of activity. The desired stability of the developed catalyst added to its potential for applicability.

Effect of preparation method on the solid state properties and the deN2O performance of CuO–CeO2oxides

“…The decomposition of N 2 O has been studied on various catalytic systems, such as transition and noble metal catalysts, perovskites, hexaluminates, spinels, zeolites, etc. 4,9,[13][14][15][16][17][18][19][20] In spite of the excellent catalytic performance of noble metal (NM)-based catalysts, their high cost and sensitivity to oxygen poisoning limit their practical applications. 9 Therefore, the development of NM-free catalysts of low cost and adequate deN 2 O performance is of crucial importance from both practical and economical points of view.…”

“…Among these, direct catalytic decomposition of N 2 O (deN 2 O) is the most promising method, due to its high efficiency and low energy requirements. The decomposition of N 2 O has been studied on various catalytic systems, such as transition and noble metal catalysts, perovskites, hexaluminates, spinels, zeolites, etc 4,9,[13][14][15][16][17][18][19][20] . In spite of the excellent catalytic performance of noble metals (NMs)-based catalysts, their high cost and sensitivity to oxygen poisoning limit their practical applications 9 .…”

Recent Progress in Hexagonal Ferrites Based Composites for Microwave Absorption

“…Barun was the first to discuss the structure of X-type hexagonal ferrite made of a stack of "S block" and "R block" in the direction of the c-axis and offered the model in stacking as "R.S.R.S.S.R*S*R*S*S*" [67] and in the R-3m space group. [105,106] Because of its outstanding magnetic and electrical properties, the X-type is suitable for electrical equipment, motors, and magnetic recording media. [107] The substitution of cations and the condition of the synthetic method determine the different electrical, magnetic, and mechanical properties.…”

Hydrothermal microwave‐assisted synthesis of LaFeO3 catalyst for N2O decomposition

“…All the noble metal based systems are supported catalysts, and the nature of the interactions of a noble metal with the support plays also a crucial role in their activity. [27][28][29] The main disadvantage of noble-metal catalysts is the high cost, so chemists are mostly looking for suitable catalytic materials from the second groupnon-noble-metal oxide catalytic systems 22 which include a wide range of oxide types such as bulk oxides, [30][31][32] spinels, 33,34 perovskites, hexaferrites, hydrotalcites [35][36][37][38][39][40][41] etc. The use of a support allows one to increase the specific activity of metal particles due to the enhanced dispersity, which is convincingly illustrated by examples of Fe 2 O 3 and Co 3 O 4 supported on ZrO 2 catalysts.…”