简介：Hybridorganic-inorganicperovskites(e.g.CH3NH3PbI3)haveattractedtremendousattentionduetotheirpromiseforachievingnext-generationcosteffectiveandhighperformanceoptoelectronicdevices.Thesehybridorganic-inorganicperovskitespossessexcellentopticalandelectronicproperties,includingstronglightabsorption,highcarrierabilities,optimizedchargediffusionlengths,andreducedchargerecombinationetc.,leadingtotheirwidespreadapplicationsinadvancedsolarenergytechnologies(e.g.highefficiencyperovskitesolarcells).However,thereisstillalackofinvestigationsregardingfundamentalpropertiessuchasferroelectricityintheseperovskites.Asconventionalferroelectricceramicsarepreparedathightemperatureandhavenomechanicallyflexibility,low-temperatureproceedandflexibleperovskiteferroelectricshavebecomepromisingcandidatesandshouldbeexploitedforfutureflexibleferroelectricapplications.Here,ferroelectricpropertiesinhybridorganic-inorganicperovskitesandseveralstate-of-theartperovskiteferroelectricsarereviewed.Novelferroelectricapplicationsofhybridorganic-inorganicperovskitesarediscussedaswell,providingguidelineforrealizingfuturehighperformanceandflexibleferroelectricdevices.