مورد إلكتروني
Novel nitrides and chalcogenides with the potential for superconductivity
| العنوان: | Novel nitrides and chalcogenides with the potential for superconductivity |
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| المؤلفون: | Campbell, Holly Jane |
| نوع الوثيقة: | Electronic Resource |
| مستخلص: | The primary aim of the work in this thesis was to design, synthesise and characterise novel superconducting materials. Inspiration for the studied materials came from information learned about conventional BCS theory materials and the high-temperature superconductors. Li3-xFexN was investigated as a potential superconductor in analogy to the known superconducting iron pnictide materials LiFeAs and LiFeP. Two methods of Li3-xFexN synthesis were studied: thermal decomposition of Li3FeN2 under Ar gas flow, and a direct synthesis between Li3N and Fe under Ar gas flow. Thermal decomposition was observed to occur in 2 steps, leading to an intermediate Li2.4Fe0.6N product, before complete decomposition to the elements. Direct synthesis was complete in one step, giving the Li2.65Fe0.35N product. The structure of Li3-xFexN is different from the pnictide superconductor analogues LiFeAs and LiFeP due to differences in the bonding arrangement between Fe and N or As/P and because Fe concentration in Li3-xFexN has never been found to approach x = 1 in previously produced samples, leading to a disordering of both Li at the (1) position and Fe. The aim of this work was to measure the properties of a sample with a higher Fe concentration than measured in literature. The band gap of Li2.65Fe0.35N was inferred to be indirect and in the IR range. In the presence of an applied magnetic field, Li2.65Fe0.35N exhibited a ferromagnetic transition below 127 K. In the absence of an applied field, Li2.65Fe0.35N behaved as a spin-glass below 105 K because of the Li(1)/Fe disorder. Both the band gap and magnetic measurements were consistent with literature on samples with slightly lower Fe concentrations. LiPdNx was successfully synthesised for the first time via a reaction between Li3N and Pd under N2 gas flow. LiPdNx was observed to adopt the hexagonal LiPd alloy structure, with N occupying trigonal prismatic positions between the Li and Pd layers. The reaction between Li3N and Pd involved 2 N |
| مصطلحات الفهرس: | Q Science (General), QC Physics, QD Chemistry, Thesis, NonPeerReviewed |
| URL: | 10.5525/gla.thesis.75074 |
| الإتاحة: | Open access content. Open access content |
| أرقام أخرى: | QCL oai:theses.gla.ac.uk:75074 Campbell, Holly Jane (2019) Novel nitrides and chalcogenides with the potential for superconductivity. PhD thesis, University of Glasgow. 10.5525/gla.thesis.75074 1127564677 |
| المصدر المساهم: | UNIV OF GLASGOW LIBR From OAIster®, provided by the OCLC Cooperative. |
| رقم الأكسشن: | edsoai.on1127564677 |
| قاعدة البيانات: | OAIster |
| الوصف غير متاح. |