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The 0.96Na0.5Bi0.5TiO3–0.04K0.5Bi0.5TiO3 (NKBT96/4) lead-free single crystal was successfully grown by top-seeded solution growth method. The effective segregation coefficient for K was calculated to be 0.20. X-ray powder diffraction measurement showed that the as-grown crystal possesses rhombohedral perovskite structure at room temperature. X-ray rock curve measure indicated that the as-grown single crystal owned relatively higher quality. The NKBT96/4 single crystal exhibits apparent diffused dielectric behavior, where the diffusiveness index α is 1.79 for the [001]-oriented crystal planes. A notable thermal hysteresis, ΔT h , of 25°C was disclosed for the tetragonal antiferroelectric-tetragonal paraelectric phase transition in the dielectric property studies between heating and cooling. The highest remnant polarization, P r , 16.8 μC/cm2, was obtained at 100°C. The electromechanical coupling coefficient kt of the [001]-oriented crystal planes at room temperature was determined to be 38% using resonance–antiresonance technique. The room temperature piezoelectric constant d33 reaches 120 pC/N.

Lead-free Na0.5Bi0.5TiO3–x%BaTiO3 single crystals of different compositions (x=0, 2, 4, 4.5 and 5.5) were grown using a top-seeded solution growth method. Temperature-dependent X-ray diffraction revealed the presence of a high-temperature tetragonal phase that existed over a narrow composition range of 0 4, rhombohedral domains were found that persisted on heating to only about Tc-150°C. Investigations of the properties revealed a dramatic increase in the dielectric constant (upto 500%), a decrease in the coercive field (300%), and an increase in the longitudinal piezoelectric constant (1000%) with modest increases in x, as the high-temperature tetragonal ferroelastic phase was suppressed and as the morphotropic-phase boundary approached.

Lead-free piezoelectric materials such as Na0.5Bi0.5TiO3-BaTiO3 (NBBT) solid solution have been paid increasing attention from an environmental perspective. In this paper, a series of NBBT single crystals with compositions near the morphotropic phase boundary (MPB) were grown by the top-seeded solution growth (TSSG) method. The compositional dependence of crystalline structure was investigated by high-resolution X-ray diffraction (XRD). In addition, the dielectric, piezoelectric and ferroelectric (FE) properties of NBBT crystals were also investigated. Excellent piezoelectric properties of NBBT crystals, especially large thickness coupling factors kt, were obtained near the MPB, which are more than or close to the performances of PZT ceramics. Moreover, the performances of NBBT crystals can be further enhanced by doping. Finally, the domain configurations of NBBT96/4 crystal were studied preliminarily.

Mn doped 0.95Na0.5Bi0.5TiO3–0.05BaTiO3 (NBBT5) single crystal was grown by the top-seed solution growth (TSSG) method. After different annealing processes, the temperature dependence of conductivity and Arrhenius relation were used to calculate the conduction activation energies and analyze the defect structure in Mn:NBBT5 crystal. Two different activation energies in different temperature regions were observed, corresponding to different conduction mechanisms. It should be noted that a large electro-strain up to 1% was obtained after being annealed in oxygen atmosphere, due to the “aged effect”.

Relaxor-based ferroelectric single crystals Mn doped 0.72Pb(Mg 1/3 Nb 2/3 )O 3 –0.28PbTiO 3 (Mn–PMN–0.28PT) were grown by the modified Bridgman technique. The effects of nitrogen annealing on structural quality, defect and electrical properties of [1 1 1]-oriented Mn–PMN–0.28PT were systematically investigated. X-ray rocking curves (XRC) were used and the results indicated that the quality of single crystals could be significantly improved by appropriate annealing. X-ray photoelectron spectroscopy (XPS) was used to investigate the content and valence states of main elements in Mn–PMN–0.28PT, including oxygen vacancies. The conduction mechanisms at different temperature ranges were discussed. The dielectric loss of annealed samples decreased about 50% compared to the unannealed one, which should be attributed to the motion of domain walls pinned by defects. The pinning effect caused by oxygen vacancies on domain wall motion was enhanced through nitrogen annealing and the pyroelectric performances were optimized.

A ternary relaxor ferroelectric single crystal Pb(In 1/2 Nb 1/2 )O 3 –Pb(Mg 1/3 Nb 2/3 )O 3 –PbTiO 3 was grown by the modified Bridgman method. The real compositions, phase structures and performances of different regions in the boule were characterized. The real composition deviated from the nominal composition, but the In/Pb ratio in the crystal remained nearly a constant. The piezoelectric coefficient d 33 , electromechanical coupling factor k 33 and coercive field E c after 〈0 1 1〉 poling can reach up to 1500 pC/N, 0.90 and 4 kV/cm, respectively. More importantly, the rhombohedral to tetragonal phase transition temperature ( T rt ) in PIN–PMN–PT single crystal with rhombohedral composition increased to 114 °C, which made the ternary system single crystal fit for the applications in wider temperature range.

(1− x )(Ni 0.8 Zn 0.1 Cu 0.1 )Fe 2 O 4 /x0.58Pb(Ni 1/3 Nb 2/3 )O 3 -0.02Pb(Zn 1/3 Nb 2/3 )O 3 -0.05Pb(Ni 1/2 W 1/2 )O 3 -0.35PbTiO 3 ((1− x )NZCF/xPNZNWT) magnetoelectric composites were prepared by conventional solid–state reaction method via low-temperature sintering technique. The low-temperature sintering technique can prepare dense composites, where the ferrite and piezoelectric phases coexist in the synthesized particulate composites, and no apparent mutual solubility takes place between the two phases. The (1− x )NZCF/xPNZNWT ceramic composites exhibit excellent integrated electrical properties, where diffused dielectric response peaks, typical P-E hysteresis loops and excellent piezoelectric property can be obtained. The (1− x )NZCF/xPNZNWT composites prepared by the low-temperature sintering process can be electrically and magnetically poled to exhibit apparent magnetoelectric effect, indicating that such technique is convenient to develop excellent particulate magnetoelectric materials in the future.

The dielectric, domain and structural properties of Na0.5Bi0.5TiO3-5.2%BaTiO3 (NBT-5.2%BT) single crystals were studied as a function of temperature in unpoled and 〈 001 〉 -poled conditions. A rhombohedral phase was found to coexist with a small volume fraction of a tetragonal one in the unpoled condition. However, in the poled condition, a single c -domain tetragonal state was found to be stable at room temperature with a piezoelectric d 33 constant of 400 pC/N. On heating above 105 °C, this single c -domain tetragonal state first transformed into an intermediate orthorhombic structure at 130 °C, and then subsequently into a rhombohedral one above 140 °C.

The complete set of elastic, dielectric, and piezoelectric constants of a 0.25Pb(In1/2Nb1/2)O3-0.47Pb(Mg1/3Nb2/3)O3-0.28PbTiO3 ternary relaxor ferroelectric single crystal after 〈011〉 poling was determined by ultrasonic and resonance methods. It exhibited a rhombohedral structure as determined by powder x-ray diffraction (XRD) and x-ray fluorescence (XRF) analysis. The electromechanical coupling factor k15 and piezoelectric coefficient d15 for shear mode are 0.93 pC/N and 2658 pC/N, and k32 and d32 for transverse mode are 0.91 pC/N and -1337 pC/N, respectively. More importantly, the rhombohedral to orthorhombic phase-transition temperature is much higher than that of PZN-0.07PT or PMN-0.29PT.

Dielectric, X-ray diffraction, and domain structure evolution for Mn-doped sodium bismuth titanate (Na 0.5 Bi 0.5 TiO 3 ) single crystals was investigated as a function of temperature. A notable thermal hysteresis was found at the tetragonal→ rhombohedral transition between heating and cooling measurements for the structural and dielectric properties. Domain studies by polarized light microscopy (PLM) revealed a corresponding thermal hysteresis at an isotropization point, where the contrast in the images disappeared but reappeared both at higher and lower temperatures. The images below the isotropization point exhibited stripe-like color bands, whose contrast became more intense and whose formation temperature on cooling was increased under electric field. Studies by piezoelectric force microscopy revealed fine-scale ferroelectric domains of about 0.1-0.3 μm in size that existed within these color bands at room temperature.

In order to better utilize the superior transverse and shear piezoelectric properties of 0.23Pb(In 1/2 Nb 1/2 O 3 )–0.45Pb(Mg 1/3 Nb 2/3 )O 3 –0.32PbTiO 3 single crystals near the morphotropic phase boundary, a complete set of elastic, dielectric, and piezoelectric coefficients of [ 1 ¯ 0 1 ] poled single crystal were determined by resonance and ultrasonic methods at room temperature. The electromechanical coupling coefficient k 32 and transverse piezoelectric coefficient d 32 can reach 0.94 and −2073 pC/N, respectively. At the same time, electromechanical coupling coefficient k 15 and shear piezoelectric constant d 15 are as high as 0.91 and 2526 pC/N. This complete set of material properties will provide convenience for device designs and fundamental theoretical studies such as applications in high-sensitivity medical ultrasonic transducers and large displacement actuators.

Mn-doped 0.948Na0.5Bi0.5TiO3–0.052BaTiO3 (NBBT94.8/5.2) lead-free single crystal with excellent piezoelectric and electromechanical coupling properties was successfully grown by top-seeded solution growth method (TSSG). X-ray powder diffraction measurement showed that the as-grown crystal possesses rhombohedral perovskite structure. The Mn-doped NBBT94.8/5.2 single crystal exhibits apparent diffused dielectric behavior, in which the diffusiveness index α is 1.99 for the [001]-oriented crystal planes. A notable thermal hysteresis is disclosed for the rhombohedral-tetragonal phase transition between heating and cooling studies in the dielectric property. The electromechanical coupling coefficients of Mn-doped NBBT94.8/5.2 were determined experimentally using the resonance–antiresonance technique. The room-temperature electromechanical coupling coefficients k 31, k 31〈110〉, k 33, k t are 35.9%, 35.5%, 68.5%, 58.7%, respectively. The room-temperature piezoelectric constants d 33, d 31 reach as high as 457, 138 pC/N respectively. The value of k t increases slightly with the increase of temperature from −80 to 70°C, demonstrating a relatively stable thermal electromechanical coupling property.

In this paper we theoretically and experimentally present a nonresonant vibration energy harvesting device based on the shear mode of 0.71Pb(Mg(1/3)Nb(2/3))O3-0.29PbTiO3 single crystals. The electrical properties of the energy harvesting device were evaluated using an analytical method. Good consistency was obtained between the analytical and experimental results. Under a mass load of 200 g, a peak voltage of 11.3 V and maximum power of 0.70 mW were obtained at 500 Hz when connecting a matching load resistance of 91 komega. A high output could always be obtained within a very wide frequency range. The results demonstrate the potential of the device in energy harvesting applied to low-power portable electronics and wireless sensors.

In this paper we fabricated the multilayer structure used as the resonance-based vibration energy-harvesting device based on 0.71Pb(Mg1/3Nb2/3)O3–0.29PbTiO3 single crystal. The performances of the device including the output voltage and power were studied systematically. Under a cyclic force of 4 N (peak value), a high output power of 4.94 mW and a corresponding peak voltage of 3.14 V were measured at 1.4 kHz with a matching load resistance of 1.0 kΩ. The results demonstrate the potential of the device in energy-harvesting applied to low-power portable electronics and wireless sensors.

A high-quality 0.96Na 0.5 Bi 0.5 TiO 3 –0.04BaTiO 3 (NBBT96/4) single crystal was grown by carefully controlled top-seed solution growth (TSSG) method. The crystal structure and electrical properties of NBBT96/4 single crystal were characterized. With the improvement of crystal quality, the values of piezoelectric constant d 33 and electromechanical coupling coefficient k t reach 283 pC/N and 50%, respectively, which obviously increased compared with NBBT96/4 grown by Pt wire. Moreover, the ferroelectric properties of as-grown crystal also enhanced obviously. The leakage current in NBBT96/4 single crystal was also discussed.

The assembly of a fluorescent pentiptycene-based ligand with copper ion resulted in the formation of a 3D porous metal-organic framework (UPC-21) based on well-known paddlewheel SBUs. UPC-21 exhibits selective adsorption of CO2 over CH4 and N2 at 273 K and 295 K, C2H2 over CH4 at 273 K. The most significant performance of UPC-21 is its highly efficient detection of NACs such as 4-NP, 1,4-DNB, NB and 1,3-DNB with the calculated quenching constants, Ksv, being 3.097 × 106, 1.406 × 106, 4.420 × 105 and 1.498 × 105 M−1 for 4-NP, 1,4-DNB, NB, 1,3-DNB, respectively, which keeps a record on the fluorescence detection of NACs. This is the first porous Cu(II) MOF that exhibits fluorescent detection of NACs with high sensitivities.

Olfaction is primarily mediated by highly specific olfactory receptors (ORs), a subfamily of which are the pheromone receptors that play a key role in sexual communication and can contribute to reproductive isolation. Here we cloned and identified an olfactory receptor, SlituOR3 (Genbank NO. JN835270), from Spodoptera litura, to be the candidate pheromone receptor. It exhibited male-biased expression in the antennae, where they were localized at the base of sensilla trichoidea. Conserved orthologues of these receptors were found amongst known pheromone receptors within the Lepidoptera, and SlituOR3 were placed amongst a clade of candidate pheromone receptors in a phylogeny tree of insect ORs. SlituOR3 is required for the EAG responses to both Z9E11-14:OAc and Z9E12-14:OAc SlituOR3 showed differential expression in S. litura populations attracted to traps baited with a series of sex pheromone blends composed of different ratios of (9Z,11E)-tetradecadienyl acetate (Z9E11-14:OAc) and (9Z,12E)-tetradecadienyl acetate (Z9E12-14:OAc). The changes in the expression level of SlitOR3 and antennal responses after SlitOR3 silencing suggested that SlitOR3 is required for the sex pheromone signaling. We infer that variation in transcription levels of olfactory receptors may modulate sex pheromone perception in male moths and could affect both of pest control and monitoring efficiency by pheromone application after long time mass trapping with one particular ratio of blend in the field.

Dielectric tunability in [001] and [110] oriented Na0.5Bi0.5TiO3–5.6%BaTiO3 crystals was investigated as functions of temperature and frequency. A tunability of the dielectric constant as high as 58% and 46% was obtained at room temperature under an electric field of E = 20 kV/cm applied along [001] and [110]. Our findings demonstrate that Na0.5Bi0.5TiO3–5.6%BaTiO3 crystals are potential voltage-tunable materials. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A giant electric field (E) induced strain of e = 0.60% has been observed for Na0.5Bi0.5TiO3–5.6%BaTiO3 single crystals under E = 20 kV/cm at 130 °C. In-situ X-ray diffraction (XRD) revealed that this induced transition was between pseudocubic and tetragonal structures. Our work provides a potential alternative to lead-based piezoelectric materials. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A lead-free magnetoelectric (ME) laminate composite consisting of thickness-polarized piezoelectric Mn-doped Na 0.5 Bi 0.5 TiO 3 –BaTiO 3 single crystal and length-magnetized magnetostrictive Tb 0.3 Dy 0.7 Fe 1.92 alloy (L-T mode), have been fabricated and its ME properties has been evaluated. The results revealed that the lead-free composite has linear magnetic-electric response in excess of 1.32 V/cm Oe at low frequency over the range of 10 −7 T H ac −3 T, the ME coefficient dramatically increases and reaches the maximized value of 18 V/cm Oe near the resonance frequency of 160 kHz. This heterostructure opens up the possibility for environment-friendly magnetic sensors.

A highly efficient plasmonic AgCl—Ag nanophotocatalyst is prepared by photochemical conversion (300 W Xe arc lamp, 20 min) of AgCl nanocubes (derived by simple polyol precipitation).

The crystallographic dependence of the DC electric (E) field induced strain and phase transition in Na0.5Bi0.5TiO3-5.6%BaTiO3 (NBT-5.6%BT) single crystals has been investigated. An induced transition between pseudocubic and tetragonal structures was observed under E = 10 kV/cm for fields applied along the < 001 > direction, whereas an induced transition between pseudocubic and rhombohedral structures was observed when the E-field was applied along < 111 >. Our results show near the morphotropic phase boundary that the phase stability of NBT-x%BT is dependent on the crystallographic direction along which E was applied. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4757877] National Science Foundation (Materials World-Wide Network) DMR-0806592 Natural Science Foundation of China 50602047 Shanghai Municipal Government 08JC1420500 Innovation Fund of Shanghai Institute of Ceramics Y09ZC4140G Ministry of Science and Technology of China through 973 Program 2009CB623305

The dielectric, ferroelectric, and electric field-induced strain response of [001]-and [101]-oriented 0.944Na(0.5)Bi(0.5)TiO(3)-0.056BaTiO(3) (0.944NBT-0.056BT) single crystals were investigated as a function of temperature and dc bias (E). An ultrahigh electromechanical response with large amplitude longitudinal piezoelectric coefficients as high as d(33)=2500 pm/V was found in [001](PC) oriented 0.944NBT-0.056BT single crystals near a depolarization temperature of T-d = 130 degrees C. In-situ XRD revealed that the enhanced piezoelectric properties resulted from a polarization extension between a polar pseudocubic phase with a slight tetragonal (P4bm) distortion and a polar tetragonal one with a large tetragonal distortion of c/a = 1.02. Our findings indicate a potential approach to high performance lead-free piezoelectrics, via polarization extension. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4709619] National Science Foundation (U.S.). Division of Materials Research. Materials World Network - DMR-0806592 United States. Department of Energy - DE-FG02-07ER46480 National Natural Science Foundation (China) - 50602047 Shanghai Municipal People's Government - 08JC1420500 Innovation Fund of Shanghai Institute of Ceramics - Y09ZC4140G China. Ministry of Science and Technology - 973 Program 2009CB623305

The ferroelectric domain and local structures of Na0.5Bi0.5TiO3-xat.%BaTiO3 (NBT-x%BT) crystals for x = 0, 4.5, and 5.5 have been investigated by transmission electron microscopy. The results show that the size of polar nano-regions was refined with increasing xat. %BT. The tetragonal phase volume fraction, as identified by in-phase octahedral tilting, was found to be increased with BT. The findings indicate that the large electric field induced strains in morphotropic phase boundary compositions of NBT-x%BT originate not only from polarization rotation but also polarization extension. (C) 2012 American Institute of Physics. [doi: 10.1063/1.3673832] National Science Foundation (Materials World Network) DMR-0806592 Department of Energy DE-FG02-07ER46480 National Science Foundation of China 50602047 Shanghai Municipal Government 08JC1420500 China Scholarship Council

A Raman spectroscopic study of Na1/2Bi1/2TiO3-x%BaTiO3 (NBT-x%BT) single crystals with x=0 and 5.6 has been performed as a function of temperature from 25 to 600 degrees C. The general features of the Raman spectra for the various compositions were similar over the region of the phase diagram investigated, with only subtle changes between rhombohedral (R), tetragonal (T) and cubic phases. The peaks were broad, with no significant narrowing on cooling through a phase transition. We find evidence of an oxygen octahedral rotational mode in the paraelectric state. On cooling near and below the ferroelectric Curie temperature, a gradual change in intensity of the A-O and B-O peaks occurred with decreasing temperature. Evidence of a ferroelectric -> antiferroelectric transition was found near 200-250 degrees C, consistent with the onset of dispersion in the dielectric constant. The phase transition mechanism was discussed. The findings indicate the presence of a broad distribution of quasistatic local structural distortions, which only have subtle differences in the various average structures. (C) 2011 American Institute of Physics. [doi: 10.1063/1.3587236] National Science Foundation (U.S.). Division of Materials Research. Materials World Network - DMR-0806592 United States. Department of Energy - DE-FG02-07ER46480 National Natural Science Foundation (China) - 50602047 Shanghai Municipal People's Government - 08JC1420500

The ferroelectric domain and local structures of Na1/2Bi1/2TiO3-x% BaTiO3 (NBT-BT) and 0.14 at. % Mn substituted Na1/2Bi1/2TiO3-x% BaTiO3 (Mn:NBT-BT) single crystals with x=5.5 near a morphotropic phase boundary have been investigated by transmission electron microscopy. Increased ferroelectric ordering and enhanced in-plane octahedral tilting were observed for Mn: NBT-BT compared with NBT-BT. Bragg-filtered lattice images revealed that the size of the in-phase tilt domains of Mn:NBT-BT were on the order of 2 to 8 nm, with a tendency of alignment along {110}. (C) 2011 American Institute of Physics. [doi:10.1063/1.3573801] National Science Foundation (Materials World Network)_DMR-0806592 Department of Energy DE-FG02-07ER46480 National Science Foundation of China 50602047 Shanghai Municipal Government 08JC1420500 China Scholarship Council

The domain structures of Na${}_{1/2}$Bi${}_{1/2}$TiO${}_{3}$-Ba${}_{x}$TiO${}_{3}$ (NBT-$x$%BT) crystals for $x$$=$0, 4.5, and 5.5 have been investigated by polarized light and piezoresponse force microscopies. The results show that BaTiO${}_{3}$ (i) refines the size of polar nanoregions and enhances their self-organization, and (ii) suppresses the formation of proper ferroelastic domains at high temperatures in the paraelectric state, and it rather favors the formation of improper ones that form below the ferroelectric Curie temperature and that elastically accommodate the ferroelectric ones.

We report on the observation of an orthorhombic ferroelectric phase in 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 single crystals, whose polarization is along 〈011〉 direction and stability can be altered by poling conditions. We studied the piezoelectric properties on poled 〈011〉 crystals, in both monodomain and polydomain states, and found that the piezoelectric d32 coefficient, which is the piezoelectric response in perpendicular to the poling direction, is positive in both cases. Based on the phenomenological theory, we show that this is possible in a crystal with the electrostrictive coefficients Q11>Q44–Q12.

Mn-doped Na0.5Bi0.5TiO3-5.6 at. %BaTiO3 (Mn:NBT-5.6% BT) single crystals were grown by a top-seeded solution growth method. Tetragonal and rhombohedral phases were found to coexist in the as-grown condition. The dielectric and structural properties were studied as a function of temperature under dc electrical bias. An induced phase stability change from rhombohedral to tetragonal phases occurred under an electric-field applied along the < 001 > direction. (C) 2009 American Institute of Physics. [doi:10.1063/1.3253412] National Science Foundation DMR0806592 Department of Energy DE-FG02-07ER46480 Natural Science Foundation of China 50602047 Shanghai Municipal Government 08JC1420500

The structural, dielectric, and piezoelectric properties of Na0.5Bi0.5TiO3-x mol. %BaTiO3 (NBT-x%BT) crystals have been investigated. The dielectric and piezoelectric properties of NBT-x%BT were enhanced near x = 5–7. High resolution synchrotron x-ray powder diffraction studies revealed the presence of a phase boundary between monoclinic (Cc) and tetragonal (P4bm) phases near x = 5–7, where the dielectric and piezoelectric properties were enhanced.

Diffuse scattering and relaxor behavior in Na0.5Bi0.5TiO3 (NBT) and NBT-5.6 at. %BaTiO3 (NBT-5.6%BT) were investigated. X-ray diffraction revealed two types of diffuse scattering in NBT: (i) broad and (ii) asymmetric L-shaped. After modification with 5.6%BT, the broad diffuse scattering patterns became narrow, and the asymmetric L-shaped ones were replaced by symmetric ones. The symmetric diffuse scattering in NBT-5.6%BT disappeared with increasing dc electric field (E) for E ≥ 9.5 kV/cm where the frequency dispersion in the dielectric constant disappeared. These results demonstrate that the relaxor characteristics are directly correlated with the diffuse scattering and the presence polar nano-regions.

Optical properties of A-site disordered Na0.5Bi0.5TiO3-x%BaTiO3 (NBT-xBT) single crystals with three typical compositions were studied systematically. Refractive index as a function of wavelength was measured by Spectroscopic ellipsometry, and modified Sellmeier dispersion equations were obtained by the least square fitting. High optical transmittance (65%) over a wide transparent region (from 400 to 6000 nm) has been found in NBT-7.5BT, much higher than that of NBT and NBT-5BT. Optical band gap energies were calculated using the absorption coefficient through Tauc equation. With increasing BT content, refractive index and absorption coefficient decrease, while transmission and band gap energy increase.

A facile 2-dimensional coupling of AgBr nanosheets with graphene oxide (GO) sheet has been developed to fabricate an efficient dual-functional visible-light-responsive GO@AgBr nanophotocatalyst. Compared to bare AgBr nanosheets, the as-obtained GO@AgBr nanocomposite exhibits enhanced photocatalytic activity towards degradation of rhodamine-B (RhB) and evolution of H2 from aqueous-methanol solution. The RhB molecules can be decomposed completely within 4 min under visible light irradiation and the catalyst can be reused 10 times without losing activity. A possible mechanism for the highly efficient photocatalyst is proposed, implying GO serves as electron acceptor to facilitate the charge transfer and suppress the recombination of electron–hole pairs. This work provides a convenient means for the exploration of highly efficient and stable GO-based composite photocatalysts.

The sorption and further application of CO2 is a highlight in the field of environmental protection and sustainable development. Lithium-containing zirconates (LixZryOz) are promising materials for high-temperature chemisorption of CO2 and have attracted tremendous interest. This review presents discussion on the recent status of LixZryOz based CO2 sorbents at high temperature. Special attention is focused on the solid state chemistry, synthetic strategies, high-temperature CO2 capture–regeneration properties and possible sorption mechanisms for LixZryOz with different Li/Zr ratios, including Li2ZrO3, Li6Zr2O7, Li8ZrO6, and Li2ZrO3 doping with alkali metals.

Heterostructured Ag@AgBr/AgCl nanocashews have been synthesized by an anion-exchange reaction between AgCl nanocubes and Br− ions followed by photoreduction. Compared to polyhedral Ag@AgBr nanoparticles, the obtained nanostructures exhibit enhanced photocatalytic activity towards decomposition of organic pollutants, i.e., rhodamine-B (RhB). For example, only 2 min is taken to completely decompose RhB molecules with the assistance of these novel heterostructured nanoparticles under visible light irradiation. Furthermore, the as-synthesized nanocatalyst can be reused 20 times without losing activity, showing its high stability. Interestingly, the novel heterostructured Ag@AgBr/AgCl nanophotocatalyst also shows efficient visible light conversion of CO2 to energetic fuels, e.g. methanol/ethanol. Therefore, the present route opens an avenue to achieve highly efficient visible-light-driven nanophotocatalysts for applications in environmental remediation and resourceful use of CO2.

Plasmonic shaped AgX:Ag (X = Cl, Br) nanoparticles have been synthesized by a facile and versatile glycerol-mediated solution route. The as-prepared AgX:Ag nanoparticles exhibit regular shapes, i.e., cube-tetrapod-like AgCl:Ag nanoparticles and AgBr:Ag nanoplates. Compared with the pristine AgX, AgX:Ag nanocomposites display stronger absorption in the visible region due to the surface plasmon resonance of silver nanoparticles. The calculation of bandgaps and band positions indicates the as-achieved AgX:Ag nanoparticles can be used as a class of potential photocatalyst for the reduction of CO(2). For example, reduction of CO(2) under visible light irradiation with the assistance of the anisotropic AgX:Ag nanoparticles yields as much as 100 μmol methanol in the products. Furthermore, the AgX:Ag nanoparticles can maintain its structure and activity after 3 runs of reactions. Therefore, the present route opens an avenue to acquire plasmonic photocatalysts for conversion of CO(2) into useful organic compounds.

Silver nanowires have been synthesized from AgCl nanocubes through a glycerol-mediated solution method with the assistance of a polymer surfactant (PVP). The influencing factors such as reaction time, PVP and temperature on the quality and quantity of the product were investigated through monitoring the reaction process using electronic microscopy. The results indicate that appropriate temperature and time are crucial to produce nanowires, whereas PVP concentration influences the diameter and length of the nanowires. The possible mechanism is proposed. The investigations of silver sources show that AgCl nanocubes are proper feedstock to acquire silver nanowires. This paper provides a new way to produce silver nanowires from insoluble salts.

In present work, lead-free single crystal 0.94Na1/2Bi1/2TiO3–0.06BaTiO3 (NBBT94/6) with dimension of Φ40 mm×10 mm was grown by a precisely controlled top seeded solution growth method. The crystal structure measurement result indicates that the NBBT94/6 single crystal exhibits the feature of rhombohedral-tetragonal phase coexistence at room temperature. The crystallographic orientation dependence of electrical properties for NBBT94/6 single crystal was investigated in detail. The remnant polarizations (Pr) of ⟨001⟩, ⟨001⟩, and ⟨111⟩ oriented crystals are 16.02 μC/cm2, 22.16 μC/cm2, and 27.23 μC/cm2, respectively. The corresponding coercive fields (Ec) are 24.89, 20.72, and 15.36 kV/cm. Moreover, a double hysteresis loop appears at the depolarization temperature. High piezoelectric properties d33 of 360 pC/N and kt of 62% were obtained in the ⟨001⟩ oriented crystals due to the engineered domain configuration which make them promising candidates for environmental friendly solid-state actuator applications.

The ferroelectric domain structure of Na1/2Bi1/2TiO3 single crystals was investigated by transmission electron microscopy (TEM) and piezoforce microscopy (PFM). Bright-field TEM and PFM images revealed the presence of polar nanodomains, whose boundaries had a tendency to align along the ⟨110⟩. High resolution TEM images revealed planar defects along these ⟨110⟩ boundaries, which partially relaxed the coherency of the lattice.

A systematic study of the optimized orientation and temperature dependence of shear-mode piezoelectric properties for ternary Pb(In1/2Nb1/2)O3–Pb(Mg1/3Nb2/3)O3–PbTiO3 (PIN–PMN–PT or PIMNT) piezocrystals was carried out. It was found that [111]-poled samples presented the best shear piezoelectric properties when driving along [11¯0] (the thickness direction). The electromechanical coupling coefficient k15 and piezoelectric coefficient d15 and g15 were found to be 96.4%, 5966 pC/N, and 0.047 Vm/N, respectively, for optimum-cut samples with platinum (Pt) electrode. Besides, the maximum service temperature for shear mode is around 105 °C, which is much higher than PMNT single crystals.

In this letter we presented a cantilever beam used for vibration energy harvesting based on shear mode 0.71Pb(Mg1/3Nb2/3)O3–0.29PbTiO3 single crystal. The working principle of the device was inferred and the factors influencing the output were obtained using an analytical method. The electrical properties under different conditions were studied systematically. Under a cyclic force of 0.05 N (peak value), a peak voltage of 91.23 V, maximum power of 4.16 mW were measured at 60 Hz with a proof mass of 0.5 g. The results demonstrate the potential of the device in energy harvesting applied to low-power portable electronics and wireless sensors.

High piezoelectric and ferroelectric properties have been found in Mn-doped Na0.5Bi0.5TiO3-BaTiO3 single crystals, which were grown by a top-seeded solution method. The electrical resistivity, dielectric constant, and ferroelectric and piezoelectric properties were all found to be notably enhanced by Mn. The piezoelectric constant d(33) and electromechanical coupling coefficients k(t) and k(31) were found to be as high as 483 pC/N, 0.56, and 0.40, respectively. These values are much higher than those previously reported for Pb-free piezoelectric crystals, demonstrating the real potential for alternative lead-free systems for sensor and piezoelectric applications. Ministry of Science and Technology of China_2008AA03Z410, 2009CB623305 Natural Science Foundation of China 60837003, 50777065, 50602047 Shanghai Municipal Government 08JC1420500 Innovation Fund of Shanghai Institute of Ceramics SCX0608 Fund of National Engineering Research Center for Optoelectronic Crystalline Materials 2005DC105003, 2007K05 National Science Foundation DMR-0806592 U. S. Department of Energy DE-FG02-07ER46480