Preparation And Mechanoluminescence Of Ce³⁺/Eu²⁺-Doped Ca₆BaP₄O₁₇

Mechanoluminescence(ML)refers to the luminescence phenomenon that directly converts mechanical energy into light energy under the action of external force(such as compression,stretching,scratching,tearing or grinding,etc.).Because of its high energy conversion efficiency,this convenient and energy-saving luminescence phenomenon has received extensive attention from researchers.Compared with other types of luminescence,ML does not require excitation sources such as additional voltage or high-energy irradiation,and its energy-saving and environmentally friendly excitation method makes ML materials used in artificial intelligence,information security,sensors,new light sources,intelligent Solid lubricants and other fields have important application potential.However,the current ML of most materials is characterized by transient luminescence,poor stability,and the need for pre-irradiation,which limits the practical application of ML materials.Therefore,it is urgent to synthesize novel ML materials with high reproducibility,stability and sustainability.Based on the above status quo,this thesis prepared Ca₆BaP₄O₁₇:Ce3+ and Ca6BaP4017:Eu2+ materials respectively,and made detailed characterization and analysis of their structure,morphology,ML properties and mechanism.The specific content of the paper is as follows:1.A blue ML material Ca₆BaP₄O₁₇:Ce3+was by high-temperature solid-state method.The composite elastomer is obtained by physically mixing the powder with polydimethylsiloxane(PDMS)in a certain proportion.The elastomer exhibits good self-recovery properties under the action of mechanical stress,and has the characteristics of continuous luminescence and afterglow.The sample with the best luminescence performance determined by the electroluminescence analysis was Ca₆BaP₄O₁₇:2%Ce3+/PDMS elastomer.The relationship of luminous intensity to stress was then investigated.Through the analysis of pyroelectric spectrum,interfacial triboelectricity and cathodoluminescence,it is finally obtained that the luminescence mechanism belongs to the model of interfacial triboelectric induced electron bombardment.2.In order to enrich the ML color of Ca₆BaP₄O₁₇ system,A ML material Ca₆BaP₄O₁₇:xEu2+(x=1.0%?1.5%?2.0%?2.5%?3.0%)was prepared by high temperature solid-phase method.The elastomer is obtained by compounding the powder with PDMS,which emits high-efficiency yellow ML under the stress stimulation of stretching,friction,extrusion and scratching.On the basis of determining the best ML elastomer,the ML properties of the elastomer were studied by stretching and friction induction.Combining the relationship between the ML properties of elastomers and traps,the relationship between triboelectricity between powder and carrier,and the physical process of bombarding powder with cathode rays to emit light.The properties of self-recovery,persistence and afterglow of the elastomeric luminescence are rationally analyzed.