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Journal of Materials Science & Technology 2013年第4期29卷 323-329页

作者： M.R.Shah A.K.M.Akther Hossain Department of Physics University of PrimeasiaBananiDhaka 1213Bangladesh Department of Physics Bangladesh University of Engineering and TechnologyDhaka 1000Bangladesh

Structural and various electrical properties of polycrystalline Ca0.5＋xNd0,5-x（Ti0.5Fe0.5）O3, prepared by standard solid state reaction technique, were studied. Formation of single phase orthorhombic structure of the compositions was confirmed by X-ray diffraction study. The composition dependence of lattice parameters, density and microstructural study show that they vary significantly with Ca content. The dielectric measurements were carried out at room temperature as function of frequency and composition. The experimental results reveal that the dielectric constant （ε′） increases with increasing Ca content. Similar behavior is observed for the dielectric loss （tanδ） and ac conductivity （σac）. In complex impedance analysis it is observed that the real part （Z′） vs imaginary part （Z″） graph exhibits a tendency of formation of a single semicircular arc for each composition of samples. Different parameters were determined by fitting the experimental data in Cole-Cole empirical formula. A dominance of grain boundary resistance （Rgb） is observed. The Rgb decreases with increasing Ca content. The high ε′ observed in present samples are suitable for fabrication of devices.

关键词： Crystal structure Dielectric properties lead free Perovskite Solid state reaction

Enhanced efficiency in lead-free bismuth iodide with post treatment based on a hole-conductor-free perovskite solar cell

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Nano Research 2018年第12期11卷 6283-6293页

作者： Jongmoon Shin Maengsuk Kim Sujeong Jung Chang Su Kim Jucheol Park Aeran Song Kwun-Bum Chung Sung-Ho Jin Jun Hee Lee Myungkwan Song Surface Technology Division Korea Institute of Materials Science (K/MS)797ChangwondaeroSungsan-GuChangwonGyeongnam642-83IRepublic of Korea School of Energy and Chemical Engineering Ulsan Nationallnstitute ofSdence &Technology(UNIST)Ulsan44919Republic of Korea Structure Analysis Group Gyeongbuk Science &Technology Promotion CenterFuture Strategy Research Institute17Cheomdangieop 1-roSangdong-myeonGumiGyeongbuk39171Republic of Korea Division of Physics andSemiconductorScience Dongguk UniversitySeou1100-715Repubfic of Korea Department of Chemistry Education Graduate Department of Chemical Materialsand Institute for Plastic Information and Energy MaterialsPusan National UniversityBusan 46241Republicof Korea

Despite the excellent merits of lead perovskite solar cells, their instability and toxicity still present a bottleneck for practical applications. Bismuth perovskite has emerged as a candidate for photovoltaic (PV) applications, because it not only has a low toxicity but is also stable in air. However, the power conversion efficiency (PCE) remains an unsolved problem. We performed band gap tuning experiments to improve the efficiency. The absorption of ABi3I10 structure films was extended within the visible region, and the optical band gap was decreased considerably compared to that for Cs3Bi2I9. Furthermore, we explained the correlation between the structure and the optical properties via a first-principles study. A device employing CsBi3I10 as a photoactive layer exhibits a PCE of 1.51% and an excellent ambient stability over 30 days.

关键词： solar cells perovskite band-gap engineering bismuth halide lead free

Multicolor emission from lanthanide ions doped lead-free Cs_(3)Sb_(2)Cl_(9) perovskite nanocrystals

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Journal of Rare Earths 2024年第5期42卷 940-946,I0005页

作者： He Shao Lifang Li Xiufeng Wu Lin Xu Biao Dong Donglei Zhou Xue Bai Hongwei Song State Key Laboratory of Organic Electronics and Information Displays&Institute of Advanced Materials College of Materials Science and EngineeringNanjing University of Posts&TelecommunicationsNanjing210023China State Key Laboratory of Integrated Optoelectronics College of Electronic Science and Engineering Jilin UniversityChangchun130012China

The toxicity of lead ions has become the severe challenge for the all-inorganic lead halide p erovskite materials,although some works have rep orted the lead-free perovskite nanocrystals(NCs),the photoluminescence quantum yield(PLQY)of these materials is still ***,because the halogen ions can be easily exchanged,the controllable multicolor emission in perovskite NCs is difficult to realize in current *** this work,we introduced lanthanide ions into lead-free Cs_(3)Sb_(2)Cl_(9) perovskite *** from the energy transfer between Cs_(3)Sb_(2)Cl_(9) perovskite NC host and lanthanide ions,the multicolor emission was *** on controlling the doping concentration of Tb^(3+)and Eu^(3+)ions,the white light emission under UV excitation would be turned easily in the Tb^(3+)/Eu^(3+)codoped *** addition,efficient energy transfer from perovskite NCs to Tb^(3+)or Eu^(3+)ions is beneficial to improving the optical properties of lead-free perovskite NCs,resulting in maximum PLQYs of red,green and white light emission of 22.6%,19.7%and 28.5%,***,a white light emitting device(WLED)was fabricated with a power efficiency of 18.5 lm/W,which presents the Commission Internationale de l'Eclairage(CIE)of(0.33,0.35).

关键词： Perovskite nanocrystals lead free Lanthanide ions Energy transfer White light emitting device Rare earths

Review on field-induced phase transitions in lead-free NaNbO_(3)-based antiferroelectric perovskite oxides for energy storage

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Journal of Materiomics 2023年第1期9卷 1-18页

作者： Mao-Hua Zhang Lovro Fulanovi Changhao Zhao Jurij Koruza Non-metallic Inorganic Materials Department of Materials and Earth SciencesTechnical University of DarmstadtDarmstadt64287Germany Institute for Chemistry and Technology of Materials Graz University of TechnologyGraz8010Austria

Emerging new applications of antiferroelectric perovskite oxides based on their fascinating phase transformation between polar and nonpolar states have provided considerable attention to this class of materials even decades after the discovery of *** presenting the challenge of formulating a precise definition of antiferroelectric materials,we briefly summarize proposed *** the following,we focus on the crystallographic structures of the antiferroelectric and ferroelectric phases of NaNbO_(3),which is emerging as a promising alternative to PbZrO_(3)-based *** field-induced phase transition behavior of NaNbO_(3)-based AFE materials in the form of single crystals,bulk ceramics,and multilayer ceramic capacitors is *** advances in a group of materials exhibiting high energy storage performance and relaxor-like behavior are also *** influence of electrode geometry on phase transition behavior and thus on the energy storage property is briefly *** review concludes with an overview of the remaining challenges related to the fundamental understanding of the scientific richness of AFE materials in terms of structure,microstructure,defect transport under high fields,and phase transition dynamics required for their future development and applications.

关键词： Antiferroelectric Perovskite oxides Energy storage NaNbO_(3) Phase transition lead free

Na/K RATIOS DEPENDENCE OF PIEZOELECTRIC AND FERROELECTRIC PROPERTIES IN(K_(1-x)Na_(x))TNbO_(3)lead-free CERAMICS

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Journal of Advanced Dielectrics 2011年第4期1卷 471-478页

作者： HONGLIANG DU SHAOBO QU ZHUO XU XIAOYONG WEI WANCHENG ZHOU DONGMEI ZHU LUO FA The College of Science Air Force Engineering University Xi'an 710051P.R.China Electronic Materials Research Laboratory Key Laboratory of Educational Ministry Xi'an Jiaotong University Xi'an 710049 P.R.China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi'an 710072 P.R.China

In order to clarify the Na/K ratios dependence of piezoelectric properties,(K_(1-x)Na_(x))TNbO_(3)cer-amics were prepared by conventional solid-state sintering at a=0.4-0.6 with a smaller com-positional interval(0.02 mol).The results demonstrate that the Na/K ratios have obvious effecton piezoelectric and ferroelectric properties of(K_(1-x)Na_(x))NbO_(3)*** and fer-roelectric properties show the maximum(d_(33)147 pc/N,k_(p)=0.40,and P_(r)=24μC/cm^(2))at=0.54,which is not consistent with conventional *** reasons should be attributedto the existence of a phase boundary at a=0.54 mol,which is similar to the morphotropic phaseboundary in Pb(Zr,Ti)O_(3)ceramics.

关键词： lead free piezoelectric ceramics piezoelectric properties morphotropic phase boundary

Towards lead-free Perovskite Solar Cells

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Towards Lead-free Perovskite Solar Cells

A review:(Bi,Na)TiO_(3)(BNT)-based energy storage ceramics

第四届新型太阳能电池学术研讨会

作者：范建东 Institute of New Energy Technology College of Information Science and TechnologyJinan University

Despite CHNHPbI perovskite solar cells have recently exhibited a significan improvement in efficiency, the Sn-based perovskite solar cells still suffer from low efficiency and poor stability that derived from the oxidation of Sn [1-4].Here, a series CHNHPb(1-x))SnI(0≤x≤1) perovskite thin films with full coverage were obtained via molecular self-assembly *** demonstrated that the electronic properties of CHNHPb(1-x))SnI(0≤x≤1) perovskite films, i.e., defect state density, carrier concentration, mobility and energy level, could be controllable by tuning the composition ratio of Pb/*** external quantum efficiency(EQE) of as-prepared solar cells were demonstrated to extend a broad absorption minimum over 50% in the wavelength range from 350 to 950 nm accompanied by a noteworthy absorption onset up to 1050 *** CHNHPbSnI perovskite solar cells with inverted structure were consequently realized with maximum power conversion efficiency(PCE) over 14%, which displayed hysteresis-free effect and stabilized power output(SPO) over 12% within 200 s at 0.6 V forward ***, we further investigated the surface and bulk recombination lifetime of carriers, as well as the transient photovoltage decay curves of devices, which were favorable to clearly understand the carrier dynamics and optimize the Sn-Pb mixed perovskite solar ***, the modified hybrid Sn-Pb perovskite solar cells were demonstrated to own superior stability and efficiency when exposed to the ambien environment without *** present study is favorable to overcome the intractable issue concerning the toxic Pb element in perovskite solar cells and step forward toward realizing the lead-free perovskite solar cells with high efficiency.

关键词： lead free perovskite solar cells carrier dynamics stability

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Journal of Materiomics 2024年第1期10卷 86-123页

作者： Wen Zhu Zong-Yang Shen Wei Deng Kai Li Wenqin Luo Fusheng Song Xiaojun Zeng Zhumei Wang Yueming Li Advanced Ceramic Materials Research Institute China National Light Industry Key Laboratory of Functional Ceramic MaterialsEnergy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi ProvinceSchool of Materials Science and EngineeringJingdezhen Ceramic UniversityJingdezhen333403China

Facing the increasingly serious energy and environmental problems,the research and development of new energy storage technology and environment-friendly energy storage materials are *** a typical lead-free ferroelectric with excellent dielectric properties,(Bi,Na)TiO_(3)(BNT)is supposed to be the most potential and competitive environment-friendly ceramic material and has become a research hotspot for dielectric energy storage in recent *** paper first briefly introduces the basic physical principles and energy storage performance evaluation parameters of dielectric energy storage materials,then summarizes the critical research systems and related progress of BNT-based lead-free energy storage materials(bulk ceramics,films and multilayer ceramics)from the aspects of ions doping modification and multi-component composite optimization,and finally looks forward to the improvement direction and energy storage application prospect of BNT-based lead-free relaxor ferroelectric materials.

关键词： Dielectrics Relaxor ferroelectrics Energy storage ceramics Sodium bismuth titanate lead free

Large electrostrain in Bi_(1/2)Na_(1/2)TiO_(3)-based relaxor ferroelectrics:A case study of Bi_(1/2)Na_(1/2)TiO3-Bi_(1/2)K_(1/2)TiO_(3)-Bi(Ni_(2/3)Nb_(1/3))O_(3) ceramics

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Journal of Materiomics 2021年第3期7卷 593-602页

作者： Guangzhi Dong Huiqing Fan Laijun Liu Pengrong Ren Zhenxiang Cheng Shujun Zhang State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an710072China Institute for Superconducting and Electronic Materials Australia Institute of Innovative MaterialsUniversity of WollongongWollongong2522Australia College of Materials Science and Engineering Guilin University of TechnologyGuilin541004China Shaanxi Province Key Laboratory for Electrical Materials and Infiltration Technology School of Materials Science and EngineeringXi’an University of TechnologyXi’an710048China

(1-x)(0.8Bi_(1/2)Na_(1/2)TiO3-0.2Bi_(1/2)K_(1/2)TiO3)-xBi(Ni_(2/3)Nb_(1/3))O3(BNKT-xBNN)solid solution ceramics were fabricated by high temperature solid-state reaction *** the compositions possess relaxor ferroelectric features,among which the ergodic BNKT-0.02BNN exhibits large repeatable electrostrain value Suni¼0.51%at electric field of 65 kV/cm,with high piezoelectric stain coefficient d33*of 890 pm/V at 45 kV/cm,while the non-ergodic compositions present unrepeatable large strain *** on the electric field-composition phase diagram,the repeatability of strain response in ergodic compositions can be attributed to the reversible electric-field-induced phase *** addition,the effects of BNN contents on the macroscopic strain properties are explored by analyzing the existing states of the polar regions with corresponding thermal evolutions and electric-field-induced phase *** research is expected to guide the design of lead free relaxor ferroelectric materials with desired electrostrain properties.

关键词： BNT Electrostrain Mechanism lead free Relaxor ferroelectric Phase diagrams

Improved dielectric energy storage performance of Pb-free 0.5Na_(0.5)Bi_(0.5)TiO_(3)-0.5SrTiO_(3) ceramics modified with CaO

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Journal of Advanced Dielectrics 2018年第6期8卷 100-107页

作者： Peng Chen Leiyang Zhang Ziyang Wang Yifei Wang Chunlin Song Jinzhu Hu Gang Liu Yan Yan Faculty of Materials and Energy Southwest University Chongqing 400715P.R.China Hanhong College Southwest University Chongqing 400715P.R.China

CaO doped 0.5Na_(0.5)Bi_(0.5)TiO_(3)-0.5SrTiO_(3)(ST)were prepared by a traditional solid-reaction method under various sintering temperatures.X-ray diffraction(XRD),electron scanning microscopy(SEM),and electrical measurements were employed to check the phases,microstructures,and energy storage *** doping of CaO can deeply affect the relaxation nature of NBT-ST *** the energy storage performance could be ***,sample with 1 at.%CaO exhibits a high energy storage density of 1.51 J/*** further details can be found within this study.

关键词： NBT based lead free dielectric energy storage

Enhanced Energy Storage Properties of La and Zr ModifiedBi0.5(Na0.82K0.18)0.5TiO3 Based Ceramics

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Enhanced Energy Storage Properties of La and Zr ModifiedBi0....