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The α-MoO 3 -based materials have been intensively investigated as chemiresistive-type gas sensors due to their excellent sensing performances for gas sensing applications. However, there still remains formidable challenges for developing a simple and scalable approach to synthesize α-MoO 3 with controllable structures. Herein, we demonstrated a glucose-assisted combustion synthesis strategy for the synthesis of α-MoO 3 materials with controllable structures. They were obtained by heat treatment of the gels containing ammonium heptamolybdate tetrahydrate and glucose. Owing to the coordination interactions between glucose and heptamolybdate, α-MoO 3 -2 sample obtained by adding 1.8 g of glucose featured the highest oxygen vacancy concentration with an O/Mo atomic ratio of 2.61. The gas sensing measurements indicated that α-MoO 3 -2 had excellent sensing performances for detecting ethanol. Such ethanol sensor displayed the lowest detection concentration of 5 ppm ethanol, high response of 3.86 toward 20 ppm ethanol, and wide detection range of 5–100 ppm. This study sheds light on preparation of metal oxides with controllable structures on a scalable way for various applications. • A glucose-assisted combustion synthesis method have been developed to preparation of MoO3 samples. • The MoO3 sample thus obtained possesses high oxygen vacancy concentration and surface chemical-adsorbed oxygen species. • The MoO3 sample exhibits excellent sensing performances for ethanol sensing. [ABSTRACT FROM AUTHOR]

Developing efficient approachs to synthesize nitrogen-doped graphene materials is significantly important. Herein, it is reported that nitrogen-doped reduced graphene oxide (N-rGO) had been successfully prepared by pyrolysis of poly(p -phenylenediamine)-rGO (P p PD-rGO) hybrids. The combined characterizations of Infrared (IR) spectra, Raman spectra, scanning electron microscopy (SEM) were used to characterize the structure of N-rGO. Most importantly, such N-rGO shows good sensing performances for simultaneous detection of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The linear ranges of the sensors for AA, DA, and UA are 0.1 mM–4 mM, 1 μM–60 μM and 1 μM–30 μM. The detection limit for detection of AA, DA and UA are 9.6 μM, 0.1 μM and 0.2 μM, respectively. This work provides a highly effective approach for preparation of graphene-based materials for electrochemical sensing applications. • Nitrogen-doped reduced graphene oxide (N-rGO) had been prepared by pyrolysis of poly(p -phenylenediamine)-rGO (P p PD-rGO) hybrids. • The N-rGO shows good sensing performances for simultaneous detection of ascorbic acid, dopamine and uric acid. • This work provides a highly effective approach for preparation of graphene-based materials for electrochemical sensing applications. [ABSTRACT FROM AUTHOR]

La 0.6 Sr 0.4 Co 0.2 Fe 0.8 O 3-δ (LSCF) is a promising cathode material for solid oxide fuel cells (SOFCs). Hence, structured LSCF coatings were deposited in this study by atmospheric laminar plasma spraying (ALPS) at the spraying distances from 150 mm to 250 mm. Particles with high temperature were obtained at low plasma arc power of only 15 kW. The microstructural characterization of the coatings showed cluster-like morphologies on the top surfaces and columnar features with large-scale vertical cracks at the cross section. An evolution mechanism of the coatings was proposed based on particle size. The movement of particles during laminar plasma jet depended on particle size, which was studied experimentally and by simulation to explain the selective deposition. The coatings showed lower polarization resistance when compared to LSCF coatings deposited by atmospheric plasma spraying (APS) due to large vertical crack densities. The high output performance of the SOFCs with the LSCF cathode also proved this phenomenon. The results suggest that ALPS provides extensive options for SOFCs manufacturing. • LSCF coatings were deposited at the long spraying distances, although at low plasma arc power of only 15 kW. • The selective deposition depended on particle size was proposed to explain various structures of coatings. • Structured coatings with large-scale vertical cracks revealed lower polarization resistances compared to APS coatings. [ABSTRACT FROM AUTHOR]

In application scenarios such as astronautics, high-altitude aircraft, medical radiography, high-energy physics, and nuclear power plants, the irradiation resistance of electronic components is one of the basic requirements for their reliability. HfO 2 -based ferroelectric films have the advantages of high CMOS process compatibility, good miniaturizability, low operating voltage, and excellent irradiation resistance, which are the core materials for the new generation of irradiation resistance ferroelectric memories. In this paper, two kinds of metal-electrode ferroelectric capacitors, W/Hf 0.5 Zr 0.5 O 2 /W (WW) and Pt/Hf 0.5 Zr 0.5 O 2 /Pt (PP), have been prepared, and three gradient γ-irradiation experiments have been carried out on the two kinds of ferroelectric capacitors. The effect of metal electrodes on the irradiation resistance of Hf 0.5 Zr 0.5 O 2 ferroelectric thin films was carefully investigated by comparing and analyzing the statistical laws of polarization change and rectangularity change before and after irradiation of a large number of devices. The experimental results show that the WW devices have better irradiation resistance than PP devices, and we further explain the irradiation resistance mechanism by first-principle calculations and finite element analysis to verify the credibility of the experimental results. Finally, we conducted a comparative test of the fatigue and wake-up characteristics of the WW devices before and after irradiation, and the results show that the prepared W/Hf 0.5 Zr 0.5 O 2 /W devices can withstand very high total γ-dose radiation, reaching up to 13.86 Mrad(Si), and they are very suitable for the application of irradiation resistant electronics. [Display omitted] • The Hf 0.5 Zr 0.5 O 2 (HZO) thin films with outstanding ferroelectric properties were prepared. • The HZO ferroelectric thin films exhibited extremely high radiation tolerance (reaching up to 13.86 Mrad(Si)). • The effect of different metal electrodes on the irradiation resistance of HZO ferroelectric thin films was analyzed. [ABSTRACT FROM AUTHOR]

Highlights: [•] HfC microcrystal chains were synthesized by a catalyst-assisted CVD. [•] The chains grow along a [001] direction and have a periodically changing diameter. [•] Single-crystal HfC core is sheathed by a thin carbon-rich shell. [•] A growth mechanism model is proposed to explain the growth of microcrystal chians. [•] This work achieves the controllable preparation of nanoscale HfC sharpening tips. [ABSTRACT FROM AUTHOR]

• Trace MoS 2 modified rGO, MWCNTs and CB were prepared. • The effect of microstructures in three carbon materials on sensing performances for CAP detection was examined. • The reasons why different carbon-based hybrids exhibit different electrochemical performances for CAP detection was also discussed. Carbon nanomaterials are considered as potentially promising sensing materials for fabrication of high-performance electrochemical chloramphenicol (CAP) sensors. However, it is highly required to investigate the structure effect of carbon supports on electrochemical sensing performances. Herein, three typical carbon nanomaterials were selected as carbon supports to deposition of trace MoS 2 , including reduced graphene oxide (rGO), multi-walled carbon nanotubes (MWCNTs) and carbon black (CB), which were subsequently used to construct electrochemical CAP sensors. The combined characterizations of Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy indicate that these MoS 2 modified carbon nanomaterials show the morphology and microstructures similar with carbon supports as used. Electrochemical tests indicate that the sensing performances of these CAP sensors are dependent on the structure of carbon supports. Among all these MoS 2 modified carbon nanomaterials, MoS 2 modified rGO hybrids display large electrochemically active surface area and low interfacial resistance between electrolyte and electrode, resulting in the highest sensitivity of 3.581 μA μM−1 cm−2. As a result, rGO is regarded as good candidate for fabrication of high-performance CAP sensors, compared to MWCNTs and CB. The present work not only clarifies structure effect of carbon supports on electrochemical sensing performances, but also provides help for the construction of high-performance electrochemical sensors and biosensors based on carbon nanomaterials. [ABSTRACT FROM AUTHOR]