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As phosphor-converted white light emitting diodes have emerged as new-generation light sources, developing phosphors with both high quantum efficiency (QE) and thermal stability is urgently required. One of the effective strategies is exploiting the nonradiative energy transfer to simultaneously improve the absorption of the activator and tune the emission of the sensitizer. In this work, we report a series of color-tunable phosphors by constructing an energy transfer system by co-doping Ce3+ and Tb3+ into Ca3Gd2Si6O18 (CGSO). We show that CGSO:Ce3+,Tb3+ not only exhibits color-tunable emission from violet (395 nm) to green (543 nm), but also possesses high internal QE (90.1%). Furthermore, we demonstrate that thermal stability can be significantly improved via efficient energy transfer from Ce3+ to Tb3+, which is mainly attributed to the fast energy transfer within the nearest Ce3+–Tb3+ pairs. Our results indicate that energy transfer from Ce3+ to Tb3+ provides a promising way to develop new green phosphors with high QE and superior thermal stability.

Design of low–cost and efficient materials with appropriate composition and configuration is desirable for supercapacitor electrode. In this work, hierarchical silica@manganese silicate core–shell spheres with controllable particle size and shell thickness are fabricated through a facile hydrothermal method. The monodispersed core–shell spheres dispaly the hierarchical structure composed of manganese silicate crystallites. The dependence of electrochemical performance on the particle size and the shell thickness is investigated. The finding demonstrates that the core–shell sphere prepared using small silica sphere possesses superior electrochemical properties. A specific capacitance of 297.3 F/g at a current density of 0.5 A/g is achieved. And the thick shell is also in favour of enhancing specific capacitance. The excellent surface–dependent electrochemical performance is associated with its distinctive hierarchical structure, which effectively shortens the ion/electron migration pathway and provides enough electroactive sites. The hierarchical core–shell spheres can be potentially applied in low–cost electrode for supercapacitor.

Transition metal oxides are considered to be ideal electrode materials for supercapacitors, but they usually suffer from poor conductivity and low capacitance. Herein, Co3O4 and NiO nanoparticles are decorated on reduced graphene oxide (rGO) to form ternary Co3O4/NiO/rGO composites using hydrothermal method. The study focuses on the dependence of the electrochemical properties on the molar ratio of cobalt to nickel, calcination temperature and rGO loading. Upon calcination at 400 °C, the Co3O4/NiO composites with a molar ratio of 1:3 display superior electrochemical performance. The adding of rGO to Co3O4/NiO composites can effectively enhance the dispersion of nanoparticles and improve the electrochemical performance overall. Compared with rGO and Co3O4/NiO, the high specific capacitance of 325 F/g at a current density of 0.5 A/g and good rate capability are achieved for ternary composites. The excellent electrochemical performance is probably attributed to the feature of cobalt and nickle oxides nanoparticles highly dispersed on rGO nanosheets. This can increase the electron conductivity, provide more exposed electroactive sites and facilitate the faradaic redox processes.

This paper reports novel binder-free and self-supported electrodes of hierarchical nickel–cobalt phosphide (NiCoP) films decorated with size-controlled Ag quantum dots by magnetron sputtering (Ag/NiCoP). Ag quantum dots with an average particle size of 7.90 nm uniformly distribute over the nanosheet-assembled architecture of NiCoP films. Benefitting from the good ohmic contact in the interfaces between Ag quantum dots and NiCoP nanosheets, Ag/NiCoP exhibits an ultrahigh specific capacitance of 6150 mF cm−2 (3050 F g−1 at 1 A g−1) higher than the 3445 mF cm−2 (1722 F g−1 at 1 A g−1) of bare NiCoP at 2 mA cm−2. The specific areal capacitance has been increased by 78.5% after introducing Ag quantum dots. 34% capacitance retention rate is achieved while the current density increases from 2 to 30 mA cm−2. The cycling stability displays a remarkable capacitance retention of 73% for 4000 cycles at 30 mA cm−2. These boosted electrochemical performances are mainly attributed to the synergistic effects of enough electroactive sites, high electronic conductivity, and easy electrolyte ion diffusion. An asymmetric supercapacitor is fabricated using hierarchical Ag/NiCoP as the positive electrode and activated carbon as the negative electrode. The supercapacitor delivers an energy density of 0.254 mW h cm−2 (1.81 mW h cm−3) at a power density of 1.88 mW cm−2 (13.4 mW cm−3). At a power density of 18.8 mW cm−2 (134 mW cm−3), an energy density of 0.115 mW h cm−2 (0.82 mW h cm−3) can still be maintained. This study provides an avenue to design a novel generation of supercapacitors for energy storage devices.

Design and preparation of two–dimensional heterostructure is an effective strategy to obtain enhanced photoelectrochemical and photocatalytic performances. Herein, two–dimensional g–C3N4/α–AgAl0.4Ga0.6O2 p–n heterostructure is for the first time synthesized by phase transition method under hydrothermal treatment. It is found that the heterostructure shows the coexistence of two phases with high crystallinity. Platelet-like α–AgAl0.4Ga0.6O2 and g–C3N4 sheets couple each other face to face, resulting in the formation of close interfaces and efficient heterojunctions. UV–vis absorption of the heterostructure is modulated efficiently by controlling the phase component. When utilized as photocatalysts for MO degradation under visible light irradiation, the g–C3N4/α–AgAl0.4Ga0.6O2 with a molar ratio of 0.75 exhibits the most excellent photocatalytic performance with a rate constant of 0.0227 min−1. The further investigation of the photoelectrochemical property including small diameter of the arc radius and maximum photocurrent indicates that the separation efficiency of electron–hole pairs is greatly improved through heterojunctions with two–dimensional coupling interfaces. Besides, the reaction kinetics and the photocatalytic mechanism related to the energy band are proposed for degrading organic pollutants. The results prove that the g–C3N4/α–AgAl0.4Ga0.6O2 heterostructure has great potential application in photocatalysis for eliminating organic pollutants.

Aurivillius phase Bi5Ti3FeO15/Na0.5Bi4.5Ti4O15 multiferroic composite films were synthesized using a sol-gel technique. Multiferroic properties and magnetoelectric coupling effect of composite films were investigated. The domain structures were clearly observed, which prove that composite films endow with good ferroelectric polarization. The maximum piezoelectric coefficient is up to 235 pm/V at 20 V, which proves that good electrostrictive and piezoelectric properties are obtained. The composite films exhibit enormous magnetoelectric voltage coefficient with αE = 410 mV/cm·Oe in magnetic field of Hbias = 7.6 kOe at room temperature, which is ascribed to good ferromagnetic, piezoelectric properties and interface coupling between Bi5Ti3FeO15 and Na0.5Bi4.5Ti4O15 layers. This work not only provides a new idea but also greatly improves the magnetoelectric effect of composite films, which makes magnetoelectric effect more effective in practice.

Silver–based solid solution with phase heterojunctions (α/β–AgAl0.4Ga0.6O2 heterostructure) was fabricated through phase transformation under hydrothermal treatment. X–ray diffraction and Raman spectra showed the phase transformation behavior, phase structure and composition of the samples. Transmission electron microscopy illustrated the mixed morphology of near–spherical β phase together with platelet α phase and the formation of phase heterojunctions. UV–vis absorption edges of the α/β–AgAl0.4Ga0.6O2 heterostructure were adjusted from 470 to 515 nm by controlling phase ratio under different hydrothermal temperatures. The heterostructure displayed the enhanced photocatalysis activity for the degradation of methyl orange in comparison to single α or β phase. In addition, electrochemical properties including small diameter of the arc radius and maximum photocurrent indicated high separation and fast transfer efficiency of the photoinduced carriers across the phase heterojunctions. Therefore, both of the enhanced utilization of visible light and efficient carrier separation of α/β–AgAl0.4Ga0.6O2 heterostructure contributed to its excellent photocatalysis property.

The pure and Mn-doped K0.5Na0.5NbO3 (KNN) films were deposited using solution-gelation method. The crystal structure, ferroelectric properties, spectral response and J-V performance of photovoltaic effect were systematically investigated. Both the ferroelectric and leakage properties are obviously enhanced for Mn-doped KNN films. A fascinating phenomenon is observed that the ferroelectric photovoltaic effect is enhanced in Mn-doped KNN films, which is originated from the improved ferroelectric polarization and narrower band gap. The transition element Nb partially substituted by Mn results in the lattice distortion and further destroys the symmetry space structure, which enhances ferroelectric polarization. And the narrower band gap effectively decreases the internal potential barrier to separate the carriers. This work gives a clear relationship between the lattice distortion, ferroelectric and photovoltaic response. It is certain that lead-free transparent K0.5Na0.5NbO3 films can be potentially applied in viable ferroelectric based solar cells.

Lead-free based Bi0.5(K0.15Na0.85)0.5TiO3 (BKNT15) films were deposited on Pt/Ti/SiO2/Si(100) substrates using a sol–gel technique. The microstructure, electric domain, dielectric relaxation, ferroelectric properties, and electrocaloric effect were investigated. The giant negative electrocaloric effect (ECE) was obtained over a broad temperature range with the maximum temperature change (ΔT) values reaching −16.55 K at working temperature of 303 K. So strong ECE is mainly attributed to high breakdown electric field and the large entropy change caused by the structural phase transition. As typical relaxation ferroelectric films, the giant negative electrocaloric effect enriches family of the electrocaloric effect, which is helpful to achieve good cooling effect in solid-state refrigeration at room temperature.

Barium and manganese-doped zinc silicates was prepared under hydrothermal treatment by mesoporous template route employing mesoporous silica as an active template. The sample displays a rod-like morphology with a mean diameter of ∼40 nm and a mean length of ∼450 nm, which inherits the characteristics of mesoporous silica. The individual rods show single crystalline and assemble into bundle-like hierarchical structure along the channels of the mesoporous silica. When barium ions together with manganese ions are co-doped in zinc silicate, the green emission corresponding to manganese ions display a significant enhancement, especially for the sample with the barium doping concentration of 0.08, which indicates that an energy transfer from barium to manganese ions takes place. With further increasing barium concentration from 0.08 to 0.10, the recombination between the defects related to barium and the excitation states of the manganese dominates accompanying non-radiative transitions which can reduce the emission efficiency.

Hierarchical and binder-free electrode materials with large electroactive sites and low contact resistance are benefit for electrochemical capacitors. Herein, this paper reports the binder-free and hierarchical ZnCo2O4 arrays decorated with carbon dots (CDs/ZnCo2O4) on nickel foam by hydrothermal route. The CDs/ZnCo2O4 arrays exhibit the nanowires-assembled hierarchical grass-like structure. The outward directed nanowires yield high surface-to-volume ratio. The nanowires exhibit the average length of 1 μm and diameter of 50 nm. The specific capacitance of the CDs/ZnCo2O4 can reach 1937 F/g higher than the 1192 F/g of bare ZnCo2O4 at 1 A/g. And 78.5% capacitance retention rate is achieved while the current density increases from 0.5 to 8 A/g. 90% of the capacitance retention over 5000 charge-discharge cycles at 15 A/g indicates high cycling stability. These boosted electrochemical performances are attributed to the structural feature with exposed electroactive sites, high electrical conductivity assisted by CDs, and opened interspaces for electrolyte ion diffusion. Asymmetric two-electrode system assembled with CDs/ZnCo2O4 and activated carbon delivers a high-energy density of 54.94 W h/kg at 425.3 W/kg and retains an energy density of 13.23 W h/kg at 6804 W/kg. This study provides a new approach to design high-performance electrode materials for supercapacitors.

Low-density ordered mesoporous CoFe2O4 (O CFO) and CoLa0.12Fe1.88O4 (O CLFO) are prepared by nanocasting method using mesoporous silica SBA-15 as a hard-template. The crystal structure, surface chemical state, magnetic properties and electromagnetic parameters are characterized by X-ray diffraction, transmission electron microscopy, N2 adsorption-desorption measurement, X-ray photoelectron spectroscopy, physical property measurement system and vector network analyzer. The results show that all the samples formed a single phase with cubic spinel structure. Meanwhile O CFO and O CLFO possess a highly ordered mesostructure. Comparing with particle CoFe2O4 (P-CFO), O CFO with high specific surface area exhibits lower magnetic saturation (Ms), higher imaginary part of complex permittivity (e′′) and imaginary part of the complex permeability (μ′′). The minimum reflection loss (RL) of O CFO reaches −27.36 dB with a matching thickness of 3.0 mm. The enhancement of the microwave absorbing performances of O CFO can be mainly attributed to the good impedance matching, high electromagnetic wave attenuation and multiple reflections of electromagnetic wave originated from the ordered mesoporous structure. The Ms of O CLFO decreases after La3+ doping, while the specific surface area, coercivity value, e′′ and μ′′ of O CLFO increase. The minimum RL of O CLFO reaches −46.47 dB with a thickness of 3.0 mm, and the effective absorption frequency bandwidth reaches 4.9 GHz.

La doped Bi5Ti3FeO15 (BTFO) multiferroic films with various doping concentration were synthesized by chemical solution deposition method. The structure, ferroelectric, magnetic properties, and magnetoelectric coupling effect were systemically investigated. Room temperature magnetoelectric effect was obtained. And the magnetoelectric coupling and magnetic exchange bias effects are regulated by the doping concentration of La. Such regulation originates from the evolution of magnetic structure derived from doping rare earth La. The coexistence of ferromagnetic (FM) and antiferromagnetic (AFM) orders can be controlled by the doping concentration of La. Thus, the superexchange interaction between FM and AFM orders was enhanced strongly, which contributes to the strong magnetoelectric coupling effect. This work provides an avenue on regulating the magnetic structure and magnetoelectric coupling effects.

BaZr 0.2 Ti 0.8 O 3 (BZT) relaxor ferroelectric (FE) films with tetragonal structure were deposited on Pt/TiO 2 /SiO 2 /Si(100) substrates via a sol-gel technique. A giant electrocaloric effect (ECE) was observed in the compact films with Δ T = 43.6 K and Δ S = 61.9 J/K kg at near room temperature of 366.5 K, which was attributed to the high breakdown electric field of E = 1010 kV/cm. Meanwhile, large negative ECE (Δ T = − 5.2 K and Δ S = − 8.8 J/K kg at room temperature of 305 K, Δ T = − 5.1 K and Δ S = − 7.2 J/K kg at near room temperature of 375 K) were achieved. The abnormal negative ECE is originated from structural transformation in relaxor ferroelectrics. The coexisting of giant negative and positive electrocaloric effects makes it more effective to realize the refrigeration during the application or removal of an electric field. The maximum electrocaloric coefficient (ζ max = 0.043 K cm/kV) and refrigeration efficiency (COP = 35.18) of the films were obtained at near room temperature of 366.5 K. The giant electroelectric effect makes BZT films promising as lead-free materials for application in environment-friendly refrigeration equipment at near room temperature.

Mixed–phase α/β–AgAl0.4Ga0.6O2 solid solution with heterojunction was fabricated through phase transformation. The samples with high crystallinity showed the mixed morphology of near–spherical shape of β phase and the platelet of α phase. The UV–vis absorption edges ranged from 460 to 520 nm by controlling the ratio of two phases. It was found that the mixed–phase α/β–AgAl0.4Ga0.6O2 with the weight percentage of 36% for α–AgAl0.4Ga0.6O2 showed the highest photocatalytic activity. This might be attributed to the absorption behavior for efficiently utilizing visible light and the phase heterojunction for promoting the separation of photogenerated carriers. The survey of photocatalytic mechanism indicated that reactive h+ and •O2− were the oxygen active species. In addition, a possible transfer process of charge carriers in photocatalysis was proposed. This work demonstrates that the design of mixed–phase heterojunction is an efficient approach to enhance photocatalytic activity.

BiOI/α–AgAl 0.4 Ga 0.6 O 2 heterostructures are synthesized by a precipitation route. The results show that flower–like BiOI microspheres grow on platelet–like α–AgAl 0.4 Ga 0.6 O 2 . With regard to the heterojunctions, the visible–light absorption edges expand from 470 to 650 nm by controlling the ratio of α–AgAl 0.4 Ga 0.6 O 2 to BiOI. Photoluminescence spectra demonstrate that the BiOI/α–AgAl 0.4 Ga 0.6 O 2 exhibits lower emission intensity than the BiOI and α–AgAl 0.4 Ga 0.6 O 2 , indicating the enhancement of carrier separation efficiency which is also verified by electrochemical impedance spectroscopy. Thus, the BiOI/α–AgAl 0.4 Ga 0.6 O 2 heterostructures can efficiently utilize visible light and facilitate carrier separation.

Ordered mesoporous Mn-doped β-Zn2SiO4-SiO2 composites are synthesized by solid state reaction at 800 °C using mesoporous silica as assisted template and silicon source. The formation temperature of β-Zn2SiO4 doped with Mn2+ is much lower than that of conventional solid state reaction, which is ascribed to the high reactivity of mesoporous silica with large surface area and porous structure. Mn-doped β-Zn2SiO4 crystals disperse in the mesoporous silica frameworks which play roles in supporting the mesoporous structure and restraining the phase transformation from β- to α-Zn2SiO4, contributing to enhancing the stability of composites. Excitation spectra of the composites show the zinc silicate absorption around 210 nm and the charge transfer band around 245 nm. Mn-doped β-Zn2SiO4-SiO2 composites exhibit an ultraviolet emission at 390 nm attributed to silica and a strong yellow emission around 575 nm driven by 4T1 to 6A1 radiative transition of Mn2+. No obvious concentration quenching is observed at high doping level of 0.08, proving the homogeneous doping of Mn2+ in the composites. This route exhibits a significant advantage of lowering the reaction temperature, facilitating easy doping and preventing concentration quenching.

Lead-free Ga 0.8 Fe 1.2 O 3 /Bi 0.5 (K 0.15 Na 0.85 ) 0.5 TiO 3 (GFO/BKNT) bilayer multiferroic composite films were fabricated on Pt(100)/Ti/SiO 2 /Si substrates via sol-gel methods. The microstructure, domain structure, ferroelectric, piezoelectric, magnetic properties as well as magnetoelectric coupling effect were investigated for the composite films at room temperature. Well-defined interfaces between GFO and BKNT layers and clear electric domain structures are observed. A strong magentoelectric effect is obtained with magnetoelectric voltage coefficient of α E =30.89 mV/cm Oe, which is attributed to excellent ferroelectric, piezoelectric, and magnetic properties, as well as the coupling interaction between ferromagnetic GFO and ferroelectric BKNT phases for lead-free bilayer composite films. Besides, GFO and BKNT demonstrate the similar perovskite structure with well lattice matching, which endows the outstanding coupling and fascinating magnetoelectric properties. The present work opens up the opportunity of lead-free magnetoelectric composite films for both further fundamental studies and practical device applications such as sensors, transducers and multistate memories.

Mesoporous magnesium silicate was prepared at 100 °C by hydrothermal method with the assisted template of mesoporous silica SBA-15 filled with carbon. The samples showed hierarchical structure composed of nanopetals and mesopores, specific surface area of 283 m 2 /g, as well as bimodal pore size distributions with the mean pore size of 3.5 and 5.0 nm. The obtained mesoporous magnesium silicate was utilized as an adsorbent for the removal of methylene blue and lead ions. The fast adsorption process of methylene blue was correlated well with the pseudo-second-order kinetics. The Langmuir isothermal model fitted the adsorption data of methylene blue and lead ion. The adsorption capacities for methylene blue and lead ion were determined to be 341 and 417 mg/g, respectively. In addition, after adsorption of methylene blue, hierarchical magnesium silicate with mesoporous structure was regenerated by calcination and still showed the adsorption capacity of 203 mg/g, which indicated its efficient reusability. This work presented an available route for the application of magnesium silicate as a promising adsorbent.

BiFeO 3 /BiVO 4 composite films have been prepared via the solution–gelation technique. The phase structure, dielectric constant, ferroelectricity, optical band-gap, photovoltaic spectral response and J–V performance were investigated. It is found that the composite films exhibit a typical ferroelectric behaviors and the improved leakage and dielectric properties. Obvious ferroelectric photovoltaic effect is obtained with high short circuit current density and open circuit voltage for BiFeO 3 /BiVO 4 composite films under the white-light illumination. And the photovoltaic spectral responses of the normalized current are near to the visible light region, which originates from the narrow band-gap of BiFeO 3 /BiVO 4 composite films. This work provides an available way of controlling ferroelectric photovoltaic response of ferroelectric films and promising applications in lighting emitting diode and other photo-electron related devices.

Micro/nanoscale magnesium silicate with hierarchical structure was synthesized by hydrothermal method using mesoporous silica SBA-15 as silicon source. The samples with well crystallinity were composed of high density nanopetals, endowing the particles with rough and porous surface. The BET surface area and the pore volume were 411 m2/g and 0.45 cm3/g, respectively. The pore-size distribution at 4.18 nm was close to that of SBA-15. The sample showed fast adsorption rate and high adsorption capacity of 353 mg/g for methylene blue. Furthermore, the adsorption process and the adsorption isotherm of methylene blue followed well with pseudo-second-order kinetics and Langmuir adsorption models, respectively.

Silver-based solid solutions as photocatalysts exhibit potential applications owing to the unique crystal and electronic structures, but single phase usually encounters low separation efficiency of photoinduced carriers and poor visible-light absorption, causing low photocatalytic activity. Thus, it is meaningful to design novel solid solution photocatalysts to solve these issues. In this work, mixed-phase heterostructures of α/β-AgAl0.4Ga0.6O2 solid solution are in-situ obtained by phase transformation of β-AgAl0.4Ga0.6O2 pre-prepared by a simple solid-state reaction. The study of phase and microstructure demonstrates that the mixed-phase heterostructure includes two phases of α and β-AgAl0.4Ga0.6O2 with high crystallinity. Platelet-like α phase is combined with polyhedral β phase, yielding close contract and large interfaces owing to in-situ preparation by phase transformation. The UV–vis absorption edge of mixed-phase heterostructure can be controlled from 500 to 575 nm through the energy band overlap of two phases. The mixed-phase heterostructure exhibits the improved visible-light photocatalytic performance. The degradation rate of tetracycline reaches 87% in comparison to the 31% for α phase and the 69% for β phase. This is mainly attributed to the enhanced carrier separation and migration efficiency verified by photoelectrochemical investigation. Especially, the photocurrent value of mixed-phase heterostructure is 5 and 7 times higher than those of β phase and α phase, respectively. Considering the practical applications, the effects of tetracycline concentration, photocatalyst dosage, pH, and coexistence anions on the photocatalysis performance were investigated for tetracycline degradation. In addition, the recyclability, oxidization species, possible photocatalytic mechanisms were also studied and proposed. This work might promote the prospective research of semiconductor photocatalysis in wastewater purification.

Visible-light responsive β-AgAl 1−x Ga x O 2 photocatalysts were prepared through a sol-gel method combined with a cation exchange reaction. The samples were characterized by X-ray diffraction, scanning electron microscopy, UV–vis absorption spectrum, and photoluminescence spectrum. The results demonstrated that the solid - solution β-AgAl 1-x Ga x O 2 with delafossite structure showed high crystallinity. The microparticles with smooth surface were polycrystal and had polyhedron crystal morphologies. The optical band gap of the β-AgAl 1−x Ga x O 2 was modulated in the range of 2.31–2.70 eV; meanwhile the photoluminescence spectra showed a red shift by varying the molar ratio of Ga/Al from 0.25 to 4 attributed to the decrease of band gap. The photo-catalytic degradation of methyl orange was studied under visible light irradiation (wavelength>420 nm). The degradation process followed the first-order kinetics. The β-AgAl 0.2 Ga 0.8 O 2 with the reaction rate of 0.0402 min −1 showed the highest photo-catalytic activity. This might be resulted from the narrow band gap of 2.31 eV for the β-AgAl 0.2 Ga 0.8 O 2 which could utilize visible light efficiently to photo-generate electrons and holes. The β-AgAl 1−x Ga x O 2 had potential applications in degrading organic dyes by using visible light efficiently.

Mesoporous materials with substantial specificities have potential applications in pollutant adsorption. In this work, ordered mesoporous magnesium silicate-silica was prepared by a facile hydrothermal method using mesoporous silica SBA-15 filled with carbon (C@SBA-15) as both assisted template and silicon source. During hydrothermal process, the carbon inside the pores of the SBA-15 supported magnesium silicate as mesoporous wall. The magnesium silicate together with the remainder silica exhibited ordered mesoporous structure, BET surface area of 432 m 2 /g, and bimodal pore size distributions. The mean pore sizes were 5.46 and 55.0 nm. The ordered mesoporous magnesium silicate-silica showed a fast adsorption rate for methylene blue; meanwhile, the adsorption capacities for methylene blue and Rhodamin B were 283 and 227 mg/g, respectively.

Semiconductor photocatalysis holds a great promise in environmental purification. Herein, layered p–n composites combining sheet–shaped Bi2WO6 with platelet–like α–AgAl0.4Ga0.6O2 were successfully prepared at 140 °C by hydrothermal method. The visible–light absorption spectra of the composites illustrate the absorption edge from 450 to 515 nm in view of the energy band overlap of two phases. Compared with pure α–AgAl0.4Ga0.6O2 and Bi2WO6, the α–AgAl0.4Ga0.6O2/Bi2WO6 composites show enhanced carrier separation efficiency, yielding improved photoelectrochemical performance. This is attributed to the in–built electric field formed at the p–n interfaces due to their different semiconductive characteristics. In addition, similar morphology of two phases also facilitates the close contact and large interfaces. This work provides a facile avenue to control the visible–light absorption and decrease the carrier recombination for semiconductor photocatalysis.

Novel composites of nickel silicate core–shell microspheres hybridized with graphene are fabricated through a facile hydrothermal method. The core–shell microspheres display hierarchical shells assemblied with Ni3Si2O5(OH)4 nanosheets yielding high specific areas, rough and porous surface. Electrochemical performance exhibits high specific capacitance of 405 F/g at 0.5 A/g together with good rate capability. This is attributed to the combination of the abundant electroactive sites resulted from hierarchical structure and the high electrical conductivity ascribed to reduced graphene. In addition, the good capacitance retention rate of 98.3% is achieved after 5000 cycles at 5 A/g.

Bilayer composite heterostructural films consisting of magnetic CoFe2O4 and multiferroic Bi5Ti3FeO15 films were prepared by the chemical solution deposition method. Morphological, ferroelectric, piezoelectric, magnetic, magneto-dielectric and magnetoelectric properties were investigated for CoFe2O4/Bi5Ti3FeO15 composite films. The magneto-dielectric and magnetoelectric effects are observed for the composite films, which is attributed to the enhanced interface coupling and mechanical strain transfer due to the small lattice mismatch between CoFe2O4 and Bi5Ti3FeO15 film layers. Magneto-dielectric and magnetoelectric anisotropies were also observed for the composite films. Correspondingly, the in-plane and out-of-plane magnetoelectric voltage coefficients reach 57 mV cm−1 Oe−1 and 78.9 mV cm−1 Oe−1, respectively. Thus magneto-dielectric and magnetoelectric anisotropies originate from the magnetic anisotropy of CoFe2O4/Bi5Ti3FeO15 composite films. The present work provides promising candidates for applications in magnetoelectric devices.

Mesoporous materials with unique structure as well as special morphology have potential applications in pollutant adsorption. In this work, using mesoporous silica SBA-15 filled with carbon (C@SBA-15) as both silicon source and assisted template, the ordered mesoporous magnesium silicate (Mg3Si4O9(OH)4) has been fabricated at 140 °C by a novel and facile hydrothermal method. During the hydrothermal process, the magnesium silicate grew along the silica walls at the expense of consuming silica and deposited on the carbon surface of the C@SBA-15. Meanwhile, the rigid carbon inside the pores of the SBA-15 supported the magnesium silicate as mesoporous walls under hydrothermal condition. The obtained magnesium silicate possessed ordered mesoporous structure, high specific surface area of 446 m2/g, large pore volume of 0.84 cm3/g, and hierarchical structure assembled with ultrathin nanosheets of 15 nm in thickness. These characteristics endow the ordered mesoporous magnesium silicate with the fast adsorption rate and high adsorption capacity of 382 mg/g for methylene blue. In addition, this synthesis method opens a new approach to fabricate other ordered mesoporous silicates.

Cluster-assembled SmCo alloy films were prepared by low energy cluster beam deposition. The structure, magnetic domain, magnetization, and magnetostriction of the films were characterized. It is shown that the as-prepared films are assembled in compact and uniformly distributed spherical cluster nanoparticles, most of which, after vacuum in situ annealing at 700 K, aggregated to form cluster islands. These cluster islands result in transformations from superparamagnetic states to magnetic single domain (MSD) states in the films. Such MSD structures contribute to the enhanced magnetostrictive behaviors with a saturation magnetostrictive coefficient of 160 × 10-6 in comparison to 105 × 10-6 for the as-prepared films. This work demonstrates candidate materials that could be applied in nano-electro-mechanical systems, low power information storage, and weak magnetic detecting devices.

Mesoporous titanium dioxide (M-TiO 2 ) and mercaptopropyl-functionalized M-TiO 2 (SH-M-TiO 2 ) were prepared as carriers for immobilization of β-glucosidase (BG). Analyses suggested that in SH-M-TiO 2 the grafted mercaptopropyl groups attributed to about 3.5% of the total weight of the matrices. For the immobilization of BG, SH-M-TiO 2 or M-TiO 2 powder was added with free BG solution and stirred at 4 °C for 8 h, followed by centrifugation and washing. BG was effectively immobilized on SH-M-TiO 2 with an enzyme activity of 10.9 U/g, which was 92.8% of the total enzyme activity in the starting solution of free BG. BG immobilized on SH-M-TiO 2 (BG-SH-M-TiO 2 ) was more stable in pH, thermal, and storage tests than BG on M-TiO 2 or free BG in solution. The K m and v max of BG-SH-M-TiO 2 were similar to values for free BG in solution. Batch hydrolysis of cellobiose-containing substrate by BG-SH-M-TiO 2 was conducted. Conversion rates of cellobiose in 10 batches were consistently around 90%. Although the residual enzyme activity of BG-SH-M-TiO 2 decreased gradually, only a small amount of BG activity was detected in supernatants. This indicated effective adsorption of enzyme molecules to SH-M-TiO 2 matrices.

Nanocomposites of ZnO encapsulated in mesoporous silica were prepared by wetness impregnation and calcination. The samples were characterized by X-ray diffraction, transmission electron microscopy, nitrogen adsorption-desorption isotherms, and X-ray photoelectron spectroscopy. The effects of ZnO content and thermal treatment on the existing form of ZnO as well as phase transformation were investigated. ZnO exists stably in the form of non-crystalline phase or cluster when crystallite size is small. With increasing ZnO content, as the size of ZnO reaches a critical size of crystalline phase, the non-crystalline ZnO or cluster transforms structurally to crystalline ZnO with low energy state. Besides, Zn2SiO4 was obtained by solid-state reaction between ZnO and mesoporous silica. The mesoporous silica acts as not only a reactant but also a diffusion barrier which inhibits the phase transformation from beta-Zn2SiO4 to alpha-Zn2SiO4. The formation temperature of Zn2SiO4 is lower than that of conventional solid-state reaction because of the unique structure of mesoporous silica.

Ordered crystalline mesoporous β-Zn2SiO4–SiO2 nanocomposites were prepared by one-step solid-state reaction using mesoporous silica as both template and silica source. Zinc oxide formed by decomposition of zinc nitrate reacts with mesoporous silica and the β-Zn2SiO4 forms and disperses inside the silica walls. The obtained β-Zn2SiO4–SiO2 nanocomposites possess hexagonal mesostructure with the β-Zn2SiO4 weight percentage below 40%. The β-Zn2SiO4 nanocrystals are surrounded by the non-crystalline silica of mesoporous walls. The non-crystalline silica acting as a binder to stick β-Zn2SiO4 nanocrystals plays a role in restraining the phase transformation from β-Zn2SiO4 to α-Zn2SiO4 and increasing the thermal stability of mesoporous β-Zn2SiO4. The crystalline mesoporous β-Zn2SiO4 may be a potential candidate for application as absorbents, for separation and as phosphors.

Zn2SiO4:Mn powders were prepared by solid-state reaction using extracted SBA-15 as silica source. The well crystalline willemite Zn2SiO4:Mn can be obtained at 800 °C, much lower than the conventional solid-state reaction temperature and lower than using the calcined SBA-15. This can be attributed to the high reactive activity of the extracted SBA-15 due to its high density silanol groups, large surface areas, and non-crystalline structure. Ultraviolet (UV) and vacuum ultraviolet (VUV) excitation spectra reveal the host lattice absorption band around 162 nm and the charge transfer transition band around 245 nm. The Zn2SiO4:Mn phosphor exhibits a strong green emission around 527 nm. The Zn2SiO4:Mn phosphor with an Mn doping concentration of 0.06, i.e., Zn1.94Mn0.06SiO4, shows the highest relative emission intensity. Upon 147 nm excitation, the luminescence decay time of the green emission of Zn1.94Mn0.06SiO4 around 527 nm is 8.87 ms.

In this study, ordered mesoporous copper oxide–silica (CuO–SiO2) composite films with CuO/SiO2 molar ratio ≤6% have been prepared. Small-angle X-ray diffraction and transmission electron microscopy investigations show that the mesoporous CuO–SiO2 composite films have a hexagonally ordered pore array nanostructure. Wide-angle X-ray diffraction analysis reveals that the copper oxide and silica in the composite films are non-crystalline. The non-crystalline CuO in the mesoporous composite films has an obvious blue-shift phenomenon of the absorption edge. The calculated band gap energy for CuO is 3.2 eV, which is much higher than its bulk counterparts (1.21–1.5 eV).

Pd nanoparticles supported in functionalized mesoporous silica were prepared. Mesoporous silica support was modified with [3-(2-aminoethyl aminopropyl)] trimethoxysilane. Palladium ions were grafted onto the functionalized mesoporous silica and reduced with hydrazine hydrate to obtain the Pd nanoparticles supported on functionalized mesoporous silica. The Pd loading in the nanocomposite of Pd supported on the functionalized mesoporous silica is 4.30 wt%. CO chemisorption analysis on the nanocomposite shows a Pd dispersion as high as 35% and a Pd surface area of 156 m2/g. The surface area, pore size, and pore volume decrease slightly with the incorporation of the Pd nanoparticles into the functionalized mesoporous silica. Pd supported on the functionalized mesoporous silica with controlled molar ratio of amino groups to palladium exhibits an excellent catalytic activity and low Pd leaching for the Heck carbon–carbon coupling reaction. The catalyst can be reused for at least six recycles in air with only a minor loss of activity.

Eu3+ ions-doped cubic mesoporous silica thin films with a thickness of about 205 nm were prepared on silicon and glass substrates using triblock copolymer as a structure-directing agent using sol–gel spin-coating and calcination processes. X-ray diffraction and transmission electron microscopy analysis show that the mesoporous silica thin films have a highly ordered body-centered cubic mesoporous structure. High Eu3+ ion loading and high temperature calcination do not destroy the ordered cubic mesoporous structure of the mesoporous silica thin films. Photoluminescence spectra show two characteristic emission peaks corresponding to the transitions of5D0-7F1 and 5D0-7F2 of Eu3+ ions located in low symmetry sites in mesoporous silica thin films. With the Eu/Si molar ratio increasing to 3.41%, the luminescence intensity of the Eu3+ ions-doped mesoporous silica thin films increases linearly with increasing Eu3+ concentration.

Palladium-containing SBA-15 (SBA-15-Pd) was synthesized via an in situ approach. In this procedure, molecular assembly template was employed as a hydrophobic carrier to provide the compatible environment for the hydrophobic compounds. The hydrophobic solvent (CHCl3) was used as a transport medium to inject the Pd precursor (Pd(acetylacetonate)2) directly into the inner core of the surfactant micelles. A 1.46 wt% Pd loading was achieved without the loss of pore ordering. Highly dispersed and uniform palladium nanoparticles could be detected using transmission electron microscopy confirming also the absence of large particles outside the mesopore silica. The catalytic activities of the SBA-15-Pd nanocomposites were investigated in Heck coupling reactions with activated and non-activated aryl substrates. The SBA-15-Pd nanocomposites exhibit excellent catalytic activities and reuse ability in air for the Heck carbon–carbon coupling reactions.

Via a specially widened anodic aluminum oxide (AAO) pore arrays, carbon nanodot arrays with uniform size and high density were obtained through filtered cathodic arc plasma (FCAP) technique. The AAO template was prepared in oxalic acid by multi-steps to get a specially enlarged opening which plays an important role in the deposition of nanodots. The morphology of the nanodots was studied by a field emission scanning electron microscopy (FESEM). The diameter of the as-prepared nanodot demonstrated here is about 100 nm at the bottom and less than 40 nm at the top, and the density was estimated to 10 10 cm −2 . Field emission properties of the nanodot arrays were investigated and a low threshold field of 5.1 V/μm at 10 mA/cm 2 was obtained. In this paper, the carbon nanodot arrays grown as replicas of the specially widened AAO template may support a strategy to realize the fabrication of nanodot arrays with various materials.

Using surfactant and hydrophobic zinc precursor as co-template, ZnO was encapsulated in mesoporous silica SBA-15 during the self-assembly process of SBA-15. The incorporation of hydrophobic zinc precursor into the cores of surfactant results in the confined growth of ZnO inside the pores of SBA-15 by calcination. A 10% weight percentage of ZnO is achieved without the perturbation of mesostructure. ZnO encapsulated in SBA-15 exists in the form of non-crystalline phase or clusters, and no large ZnO particles outside the pores of SBA-15 are formed. Photoluminescence spectra show a blue shift owing to the quantum size effects.

Acidic (leucine-rich) nuclear phosphoprotein 32 family, member A (ANP32A), has multiple functions involved in neuritogenesis, transcriptional regulation, and apoptosis. However, whether ANP32A has an effect on the mammalian developing brain is still in question. In this study, it was shown that brain was the organ that expressed the most abundant ANP32A by human multiple tissue expression (MTE) array. The distribution of ANP32A in the different adult brain areas was diverse dramatically, with high expression in cerebellum, temporal lobe, and cerebral cortex and with low expression in pons, medulla oblongata, and spinal cord. The expression of ANP32A was higher in the adult brain than in the fetal brain of not only humans but also mice in a time-dependent manner. ANP32A signals were dispersed accordantly in embryonic mouse brain. However, ANP32A was abundant in the granular layer of the cerebellum and the cerebral cortex when the mice were growing up, as well as in the Purkinje cells of the cerebellum. The variation of expression levels and distribution of ANP32A in the developing brain would imply that ANP32A may play an important role in mammalian brain development, especially in the differentiation and function of neurons in the cerebellum and the cerebral cortex.