Bio-inspired flexible vibration visualization sensor based on piezo-electrochromic effect

Monitoring structural vibration can provide quantitative information for both structural health evaluations and early-warning maintenance.The most classic vibration-based structural health monitoring is equipped with piezoelectric accelerometers,which is expensive and inconvenient due to cumbersome and time-consuming sensor installation and high power-consumptive data acquisition systems.One other main challenge with these systems is the inherent limitations for multi-point monitoring in critical elements with curvature due to their non-conformability.Here,inspired by the chameleon,we report a cost-effective,flexible and conformal,self-powered vibration sensor based on elasto-electro-chemical synergistic effect of piezoelectricity and electrochromism.The sensor can provide not only in-situ visualization,but also ex-situ recording of structural vibration due to the non-volatile color memory effect of electrochromism.The passive sensor system is composed of two distinct electronic components d ternary Pb(In1/2Nb1/2)O_(3)ePb(Mg1/3Nb2/3)O_(3)ePbTiO_(3)piezoelectric single crystal ribbon sensors and a solid-state tungsten trioxide electrochromic indicator driven by vibration-induced voltage generated by the piezoelectric ribbons.The proposed piezo-electrochromic based passive non-volatile visualization sensor may find diverse applications in structural health monitoring,smart wallpapers,and medical injury rehabilitation.

Strong ferroelectric and luminescence properties of 0-3 type 0.8BaTiO_(3)-0.2CaTiO_(3):Pr^(3+)composite ceramics prepared by cold sintering process

0-3 type ferroelectric-phosphor composite ceramics cannot be prepared by the traditional solid-state sintering(SSS)method due to the strong chemical reaction between ferroelectrics and phosphors during high-temperature sintering.The cold sintering process(CSP)may solve this issue by densifying ceramics at ultralow sintering temperatures.In this work,dense 0-3 type 0.8BaTiO3-0.2CaTiO3:Pr^(3+)(0.8BT-0.2CT:Pr^(3+))binary composite ceramics were fabricated at an ultralow temperature of 225℃via CSP with the Ba(OH)2·8H2O hydrated flux.The effects of the Ba(OH)2·8H2O content,sintering temperature,and sintering time on the microstructure and densification of the ceramics were investigated.The density of the composite ceramics prepared by the optimized sintering parameters reaches 89%.Both energy-dispersive X-ray(EDX)spectroscopy and X-ray diffraction(XRD)confirm the existence of BT and CT:Pr^(3+)phases in the prepared ceramics.A strong ferroelectric performance is obtained,and the luminescent properties of CT:Pr^(3+)are preserved for the ceramics.Furthermore,the 0.8BT-0.2CT:Pr^(3+)composite ceramics prepared by CSP have stronger photoluminescence and photo-stimulated luminescence than their counterparts prepared by cold sintering assistance(CSA)and SSS methods.Therefore,CSP is a promising method for combining luminescent and ferroelectric properties into 0-3 type composite ceramics.