{"doi":"10.58088/5j9a-pj93","title":"Experimental studies of solid-state reactions in nanoscale systems","abstract":"\"This work focuses on the size-dependence of select properties in several nanoscale metallic and oxide systems, including lattice parameter and grain size evolution during diffusion and sintering processes in platinum nanoparticles and nanoscale platinum/nickel systems as well as the activation energies of the oxidation/reduction reactions required to produce nanoscale Sm-Co alloys from Sm-Co-O precursors. The activation energies of the reduction/oxidation reactions required to produce metallic Sm-Co alloys from Sm-Co-O have been examined via thermogravimetric analysis (TGA). Precursor oxides were synthesized via an autocombustion process and characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). TGA measurements determined the activation energy of a SmCoO3 to Sm2O3+CoO nanoscale mixture was 1.29eV/atom, and the activation energy of the subsequent conversion of CoO to metallic Co was 2.11eV/atom, several times larger than the bulk reported value. The conversion of Co3O4 to CoO was found to be 1.04eV/atom, and though the activation energy of the subsequent CoO to metallic Co in the absence of Sm2O3 could not be quantified, it was determined to be much smaller than 1.04eV/atom, and by extension much smaller than the 2.11eV/atom measured for the same transition in the presence of Sm2O 3. In addition, an in-situ optical pump/x-ray probe technique was used to study the evolution in the size and lattice parameter of aggregated single crystal Pt nanoparticles prepared by a seed-growth method. The as-prepared Pt particles were characterized by XRD and transmission electron microscopy (TEM). Photo-excitation of the as-prepared particles resulted in a monotonic particle growth and a rapid increase in lattice parameter that transitioned from monotonic at low incident laser fluence to non-monotonic at high incident laser fluence. As a result, the lattice parameter of the Pt nanoparticles did not evolve with a simple inverse grain size dependence. This result was compared to conventional sintering measurements in which a more typical size and lattice parameter evolution was observed.\"","journal":"Library, Museums and Press - UDSpace (University of Delaware)","year":2024,"id":492860,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.9509,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2024-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":1339061,"name":"Brian Kelly","orcid":"0000-0003-3016-1262","position":0,"is_corresponding":true}],"reference_count":0,"raw_metadata":null,"created_at":"2026-07-19T02:08:56.210382Z","pmid":null,"pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}