Study of structural and transport properties of nanostructured CeO₂, Ce_1−xRu_xO₂ and Ce_1−xIn_xO₂ thin films

Abstract

The present work reports for the first time thin films prepared from Ce 1Àx M x O 2Àd (M ¼ Ru, In) solid solutions for application as gas sensors. The CeO 2 , Ce 0.95 Ru 0.05 O 2 and Ce 0.95 In 0.05 O 2 thin films were prepared by means of the RF sputtering process onto Si (111) substrates. The deposition conditions were carried out at 500 8C varying the deposition time. Targets were prepared via sol-gel process starting from C 6 H 9 O 6 In, Ru 3 (CO) 12 and Ce(C 2 H 3 O 2 ) 3 Á 1.5H 2 O compounds and using a ceramic method to consolidate them. The samples were characterized by means of XRD, SEM, and AFM. Their thickness was measured using a profilometer. The results herein obtained regarding the microstructure and transport properties indicate that these materials can be used as gas sensors.

Growth, characterization and interfacial reaction of magnetron sputtered Pt/CeO2 thin films on Si and Si3N4 substrates

“…It is to be noted that peaks related to Pt metal, PtO or PtO 2 cannot be detected in both the films indicating that Pt is incorporated as ions into CeO 2 lattice, which agrees well with works on Pt/CeO 2 powder catalysts done by Bera and coworkers . Incorporation of Ru 4+ and In 3+ into CeO 2 matrix has been reported in the literature . Grain sizes calculated from Scherrer formula are 4.5 and 4.3 nm for Pt/CeO 2 /Si and Pt/CeO 2 /Si 3 N 4 , respectively.…”

“…. A broad peak at 33.2° noticed in both the films is indexed into CeO 2 (200) reflection indicating the nanocrystalline nature of the films . Presence of only (200) diffraction peak in Pt/CeO 2 /Si film indicates that the film structure on Si substrate is orientated preferentially to (200) plane of CeO 2 .…”

High‐Throughput Screening of High‐Entropy Fluorite‐Type Oxides as Potential Candidates for Photovoltaic Applications

“…A similar behavior was observed in fluorite‐structured CeO 2 , where doping with Ru or In also led to a decrease in charge carrier density and an increase in mobility to 583 cm 2 V −1 s −1 . [ 28 ]…”

“…Oxides with fluorite structure are an emerging class of materials that offer many promising properties for a wide range of electronics and energy applications. [23][24][25][26][27][28] In particular, the ability to achieve semiconducting properties in certain compositions makes them attractive for energy and optoelectronic applications. Here, we deliberately populated the cation site of the crystal stepwise with an equimolar choice of up to seven rare-earth (RE) metals, therefore entering the realm of high-entropy materials with a configurational entropy of >1.5R (R being the ideal gas constant).…”

Ce_(1-x)M_XO₂, {M=Ru, In} Solid Solutions as Novel Gas Sensors for CO Detection

“…CeO 2 exhibits high mobility of oxygen on its surface and also, inside the lattice (bulk level). Commonly, metals added to CeO 2 like In or Ru, among others, has been demonstrated to improve catalytic and transport properties [10]. Also InO 2 has been reported to be a good sensor for specific applications of ozone [11,12] and NO 2 detection [13,14,15].…”