Journal of Inorganic Materials is supervised by Chinese Academy of Sciences and sponsored by Shanghai Institute of Ceramics and Chinese Academy of Sciences (CAS). Published by The Science Press and launched in 1986, it is a monthly journal with 112 pages per issue. It aims to report phased and final achievements of national key projects and the projects of National Natural Science Foundation of China. Its scope covers creative treaties on new inorganic non-metallic materials, including nano-inorganic materials, functional and structural ceramics, functional crystals, energy materials, biomaterials, solid thin film, special glass and inorganic composite. It aims at briefly reporting on achievement obtained at different stages, summarizing and reviewing on the progress of special areas or subjects of inorganic non-metallic materials, and new processes and new techniques.
The journal is included in CA, SCI, JST, EI, CSCD.
Nano-structured tungsten oxide (WO
3) thin films were deposited at room temperature by glancing angle reactive magnetron sputtering and then annealed at 450 ℃ in air. The films were characterized by field-emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD). The WO
3 thin film deposited by DC magnetron sputtering at 80° glancing angle exhibited oblique nano-column structure, while that deposited by pulsed DC magnetron sputtering at the same angle exhibited nano-pore structure. After annealing at 450 ℃ for 3 h, the oblique nano-columns were conjunct with each other but the nano-pore structure remained with bigger pore size. The XRD analysis revealed that the WO
3 thin films deposited at room temperature demonstrated amorphous structure and would transfer to monoclinic phase after annealing at 450 °C for 1 h. The transmittance difference between the colorization and bleaching of the nano-structured WO
3 thin film reaches 60% at the wavelength of 600 nm. The electrochromic properties of nano-structured WO
3 thin films are highly reversible.
As one of the most widely used oxide in many fields, Y
3Al
5O
12 (YAG: yttrium aluminum garnet) has attracted extensive attention. However, due to its high melting point and complex mechanism for phase selection, accurate knowledge of thermo-physical properties for YAG melt, is much desired. Using an advanced aerodynamic levitation laser-melting technique, here the viscosity, surface tension and density were carefully evaluated on both thermodynamically stable, and metastable supercooled YAG melts in the temperature scope from 1750 K to 2650 K. The results indicate that the density of YAG melts has a higher sensitivity than that of Al
2O
3 melts upon temperature change; the YAG melts have one time higher average line thermal expansion coefficient compared to the Al
2O
3 melts. Al
2O
3 melts’ surface tension is almost constant on temperature in the wide temperature scope, while the YAG melts have a distinct decrease in surface tension with the increase of temperature. As to the viscosity–temperature relation, in the supercooled region, YAG melts have a more obvious rise in viscosity upon cooling.
The effects of different heat-treatment process on the crystallization, phase composition and content, and microstructure of 19MgO–23Al
2O
3–53SiO
2–4TiO
2–2.5B
2O
3 (wt%, M–A–S–T–B) were studied by means of differential scanning calorimeter (DSC), X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. The influences of different nucleation and crystallization time on the microwave dielectric properties were discussed as well. The results showed that, based on the controlled crystallization mechanism of glass, MgSiO
3 phase was precipitated adequately for the M–A–S–T–B samples heat-treated at 850 ℃/2 h + 950 ℃/2 h, and also, the α-cordierite,
xMgO–
yAl
2O
3–
zSiO
2 and α-SiO
2 phases could be precipitated from matrix phase. Additionally, with the increase of nucleation time, the crystal types and phase content were found no discernible changes in the M–A–S–T–B glass-ceramics. When the crystallization time increased to 20 h, the crystallized volume fraction of the glass increased, leading to the improvement of the quality factor (
Q ×
f) and the obvious precipitation of granular grains. However, the dielectric loss slightly increased and the relative density of samples decreased with the further increase of crystallization time (30 h). Wherein, the M–A–S–T–B glass-ceramic sample heat-treated at 850 ℃/2 h + 950 ℃/20 h exhibited the excellent microwave dielectric properties of
εr = 3.85,
Q ×
f = 12 740 GHz (at 13.973 GHz) and
τf = −5.37 × 10
–6/ ℃.
Bottom-up assembly of nanoparticles into new materials with subwavelength features has become an important means to manipulate and utilize light. Here, we reported a novel nano-assembly technology, named silicon oil two-step dehydration method. This method utilizes the rheological and confinement effects of the oil-water interface and enables the assembly of 15 nm titanium dioxide (TiO
2) nanoparticles into macroscopic hemispherical optical lenses with a high refractive index and high transparency. The TiO
2 lens can be large-scale produced with this method. Moreover, the assembly process and mechanism were analyzed in details. In addition, this method can also achieve uniform composites of TiO
2 nanoparticles with other nanomaterials, such as gold (Au) nanoparticles, Au nanorods, Au nanocubes or graphene oxide, enabling the preparation of TiO
2/Au or TiO
2/graphene oxide composite devices. Among them, after the recombination of TiO
2 nanoparticles, the surface plasmon absorption peaks of Au nanoparticles, Au nanorods or Au nanocubes have a significant red shift, indicating that this assembly method provides an effective way for the preparation of functional composite optoelectronic devices in the future.
Ni doped woodceramics were prepared from papermaking black liquor lignin and NiCl
2·6H
2O, which were sintered at 1200 °C and then activated with KOH. The Ni doped activated graphite woodceramics presents 3-D net structure with foam formation. X-ray diffractometer, Raman spectrometer, scanning electron microscope, transmission electron microscope, specific surface area tester, and electrochemical workstation were employed to characterize the samples. The results show that Ni constructs the framework of woodceramics and catalyzes the graphitization of amorphous carbon. The sample displays obvious graphitization tendency, and the graphene lamellar structure is found. The lattice spacing is close to the lattice parameter of ideal graphite. Meanwhile, activating treatment can effectively form hierarchical pores and increase the quantity of micropores and ultramicropores. The pore diameter mainly concentrates at 3.60 nm, and the specific surface area increases from 359 m
2·g
−1 to 856 m
2·g
−1, as the sample is activated at 800 °C for 3 h. Additionally, activation improves the electrochemical performance of Ni doped woodceramics, whose specific capacitance is 153.8 F·g
−1 at 20 mV·s
−1 scanning rate, 2.2 times higher than that of the non-activated sample.
(1−
x)(Bi
0.5Na
0.5)
0.935Ba
0.065TiO
3-
xBiScO
3 (BNBT-
xBS) lead-free ceramics were fabricated by conventional ceramic sintering process and modified by BiScO
3. The effects of BiScO
3 content on the microstructure, energy storage, field-induced strain and dielectric properties of BNBT-xBS ceramics were investigated. The results indicated that the structure of BNBT-
xBS ceramics without impurity phase transferred from the co-existence phase of rhombohedral and tetragonal phase to pseudo-cubic phase. The average grain size of BNBT-
xBS ceramics grew slightly with increment of doping content. The long-range ferroelectric order of BNBT-
xBS ceramics was destroyed by BiScO
3, which resulted in weak polarization. Meanwhile, the phase transition of BNBT-
xBS ceramics was observed from a typical ferroelectric phase to relaxor phase. BiScO
3 dopants improved the energy storage and strain performance of ceramics as well, whose maximum energy storage density and high strain were 0.46 J/cm
3 and 0.25% at 70 kV/cm. The dielectric constant decreased with doping content increasing. The relaxor ferroelectric characteristics were also verified by the temperature-dependent dielectric spectra. The resistance of BNBT-
xBS ceramics illustrated a negative temperature coefficient and excellent electrical insulativity below 450 °C.
CdS/TiO
2 heterojunction films have attracted much attention in the field of photocatalysis due to their excellent photocatalytic performance under visible light irradiation. However, the CdS/TiO
2 films prepared by the conventional methods may exhibit loose interface, leading to poor transport of photogenerated carriers at the interface. In this study, CdS/TiO
2 heterojunction films were successfully prepared by in-situ transformation (TiO
2→CdTiO
3→CdS). The morphologies and structures of the as-prepared films were characterized by XRD, SEM and TEM. The results showed that the CdS formed on the surface of TiO
2 nanoparticle, and the interface of CdS/TiO
2 heterojunction was compact. Their photoelectrochemical (PEC) performance was investigated by electrochemical working station. The results indicate that the CdS/TiO
2 films prepared by in-situ method, whose photocurrent density is as high as 9.8 mA·cm
−2 at 0.4 V (vs. RHE), present higher PEC activity than those prepared by successive ionic layer adsorption and reaction (SILAR). The electrochemical impedance spectroscopy (EIS) results show that the in-situ synthesized CdS/TiO
2 films have lower charge transfer resistance, which reveals that the in-situ formed compact interface can reduce the charge transfer resistance at the CdS/TiO
2 interface, restrict the recombination of photogenerated carriers, and further enhance the PEC performance.
