We have investigated dielectric properties of aromatic polythiourea(ArPTU,a polar polymer containing high dipolar moments with very low defect levels)thin films that were developed on Pt/SiO_(2) substrate.The detected...We have investigated dielectric properties of aromatic polythiourea(ArPTU,a polar polymer containing high dipolar moments with very low defect levels)thin films that were developed on Pt/SiO_(2) substrate.The detected response is compared to the response of commercially available polymers,such as high density polyethylene(HDPE)and polypropylene(PP),which are at present used in foil capacitors.Stable values of the dielectric constantε'≈5(being twice higher than in HDPE and PP)over broad temperature and frequency ranges and dielectric losses as low as in commercial systems suggest ArPTU as a promising candidate for future use in a variety of applications.展开更多
K_(0.5)Na_(0.5)NbO_(3)-SrTiO_(3)(KNN-STO)thin films of different compositions were prepared by the chemical solution deposition method.While structural investigations confirmed the formation of perovskite solid soluti...K_(0.5)Na_(0.5)NbO_(3)-SrTiO_(3)(KNN-STO)thin films of different compositions were prepared by the chemical solution deposition method.While structural investigations confirmed the formation of perovskite solid solution in all developed films,dieletric experiments revealed a relaxor broad dispersive maximum in the sample with 15 mol%of STO,exhibiting for a thin film high ε′~330 at~210K.The history-dependent effects of this relaxor sample were compared to those of KNN STO ceramics and,furthermore,shown to be much weaker than in widely used lead-based ferroelectric and relaxor(Pb,L a)(Zr,Ti)O_(3) ceramics:While fatigue endurance results revealed a slight drop in polarization after 3 × 10^(5) switching cycles,the results of aging of the dielectric constant revealed no notable decrease in its values after 10^(6)s.展开更多
基金This project was financially supported by the Slovenian Research Agency under program P1-0125the Ministry of Education,Science,and Sport of Republic of Slovenia and European Social Fund under project PR-05648the Office of Naval Research(ONR)under Grant No.N00014-14-1-0109.
文摘We have investigated dielectric properties of aromatic polythiourea(ArPTU,a polar polymer containing high dipolar moments with very low defect levels)thin films that were developed on Pt/SiO_(2) substrate.The detected response is compared to the response of commercially available polymers,such as high density polyethylene(HDPE)and polypropylene(PP),which are at present used in foil capacitors.Stable values of the dielectric constantε'≈5(being twice higher than in HDPE and PP)over broad temperature and frequency ranges and dielectric losses as low as in commercial systems suggest ArPTU as a promising candidate for future use in a variety of applications.
基金This project was financially supported by Slovenian Research Agency under programs P1-0125 and P2-0105 and projects PR-02908,J2-1227,and PR-03099by Ministry of Education,Science and Sport of Republic of Slovenia under Project PR-05648.
文摘K_(0.5)Na_(0.5)NbO_(3)-SrTiO_(3)(KNN-STO)thin films of different compositions were prepared by the chemical solution deposition method.While structural investigations confirmed the formation of perovskite solid solution in all developed films,dieletric experiments revealed a relaxor broad dispersive maximum in the sample with 15 mol%of STO,exhibiting for a thin film high ε′~330 at~210K.The history-dependent effects of this relaxor sample were compared to those of KNN STO ceramics and,furthermore,shown to be much weaker than in widely used lead-based ferroelectric and relaxor(Pb,L a)(Zr,Ti)O_(3) ceramics:While fatigue endurance results revealed a slight drop in polarization after 3 × 10^(5) switching cycles,the results of aging of the dielectric constant revealed no notable decrease in its values after 10^(6)s.
