The application of antimony sulfide(Sb_(2)S_(3))has been limited mainly to the energy storage and photoelectric conversion fields.However,in this work,the application of Sb_(2)S_(3) is extended to the field of electro...The application of antimony sulfide(Sb_(2)S_(3))has been limited mainly to the energy storage and photoelectric conversion fields.However,in this work,the application of Sb_(2)S_(3) is extended to the field of electromagnetic(EM)wave absorption for the first time.High-permittivity Sb_(2)S_(3) singlecrystal nanorods were prepared successfully and exhibited excellent performance,with a low reflection loss of -65.9 dB(13.0 GHz,3.8 mm)and an ultra-wide effective absorption bandwidth of 9.5 GHz(8.5-18.0 GHz,4.1 mm).After excluding the general absorption mechanisms,including conductive losses,interfacial polarization,and dipole polarization,the distinctive single-crystal volume polarization affected by shape anisotropy was proposed.This work not only meets the challenge of a single-component dielectric material design but also introduces a new concept for construction of efficient dielectric EM wave absorption material.展开更多
In recent years, with the growing concerns on environmental protection and human health, new materials, such as lead-free piezoelectric materials, have received increasing attention. So far, three types of lead-free p...In recent years, with the growing concerns on environmental protection and human health, new materials, such as lead-free piezoelectric materials, have received increasing attention. So far, three types of lead-free piezoelectric systems have been widely researched, i.e., perovskites, bismuth layer-structured ferroelectrics, and tungsten-bronze type ferroelectrics. This article presents a new type of environmental friendly piezoelectric material with simple structure, the transition-metal(TM)-doped ZnO. Through substituting Zn2+ site with small size ion, we obtained a series of TM-doped ZnO with giant piezoresponse, such as Zno.975Vo.o250 of 170 pC/N, Zn0.94Cr0.06O of 120 pC/N, Zn0.913Mn0.0870 of 86 pC/N and Zn0.988Fe0.0120 of 127 pC/N. The tremendous piezoresponses are ascribed to the introduction of switchable spontaneous polarization and high permittivity in TM-doped ZnO, The microscopic origin of giant piezoresponse is also discussed. Substitution of TM ion with small ionic size for Zn2+ results in the easier rotation of noncollinear TM-O1 bonds along the c axis under the applied field, which produces large piezoelectric displacement and corresponding piezoresponse enhancement. Furthermore, it proposes a general rule to guide the design of new wurtzite semiconductors with enhanced piezoresponses. That is, TM-dopant with ionic size smaller than Zn2+ substitutes for Zn2+ site will increase the piezoresponse of ZnO significantly. Finally, we discuss the improved per- formances of some TM-doped ZnO based piezoelectric devices.展开更多
基金supported by the National Natural Science Foundation of China(51572157,21902085,and 51702188)the Natural Science Foundation of Shandong Province(ZR2019QF012)+1 种基金the Fundamental Research Funds for the Central Universities(2018JC046)Young Scholars Program of Shandong University(2018WLJH25)。
文摘The application of antimony sulfide(Sb_(2)S_(3))has been limited mainly to the energy storage and photoelectric conversion fields.However,in this work,the application of Sb_(2)S_(3) is extended to the field of electromagnetic(EM)wave absorption for the first time.High-permittivity Sb_(2)S_(3) singlecrystal nanorods were prepared successfully and exhibited excellent performance,with a low reflection loss of -65.9 dB(13.0 GHz,3.8 mm)and an ultra-wide effective absorption bandwidth of 9.5 GHz(8.5-18.0 GHz,4.1 mm).After excluding the general absorption mechanisms,including conductive losses,interfacial polarization,and dipole polarization,the distinctive single-crystal volume polarization affected by shape anisotropy was proposed.This work not only meets the challenge of a single-component dielectric material design but also introduces a new concept for construction of efficient dielectric EM wave absorption material.
基金supported by the National Hi-tech (R&D) Program of China (Grant Nos. 2007AA03Z426 and 2009AA034001)the National Natural Science Foundation of China (Grant Nos. 50871060 and 50772055)the National Basic Research Program of China (Grant No. 2010CB832905)
文摘In recent years, with the growing concerns on environmental protection and human health, new materials, such as lead-free piezoelectric materials, have received increasing attention. So far, three types of lead-free piezoelectric systems have been widely researched, i.e., perovskites, bismuth layer-structured ferroelectrics, and tungsten-bronze type ferroelectrics. This article presents a new type of environmental friendly piezoelectric material with simple structure, the transition-metal(TM)-doped ZnO. Through substituting Zn2+ site with small size ion, we obtained a series of TM-doped ZnO with giant piezoresponse, such as Zno.975Vo.o250 of 170 pC/N, Zn0.94Cr0.06O of 120 pC/N, Zn0.913Mn0.0870 of 86 pC/N and Zn0.988Fe0.0120 of 127 pC/N. The tremendous piezoresponses are ascribed to the introduction of switchable spontaneous polarization and high permittivity in TM-doped ZnO, The microscopic origin of giant piezoresponse is also discussed. Substitution of TM ion with small ionic size for Zn2+ results in the easier rotation of noncollinear TM-O1 bonds along the c axis under the applied field, which produces large piezoelectric displacement and corresponding piezoresponse enhancement. Furthermore, it proposes a general rule to guide the design of new wurtzite semiconductors with enhanced piezoresponses. That is, TM-dopant with ionic size smaller than Zn2+ substitutes for Zn2+ site will increase the piezoresponse of ZnO significantly. Finally, we discuss the improved per- formances of some TM-doped ZnO based piezoelectric devices.