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The rGO/BiOBr/Bi4O5Br2 nanocomposite powders with stacked nanosheets were fabricated by one‐step solvothermal method. The components, morphologies, optical properties and the separate of photo‐induced carriers were explored by XRD, FT‐IR, SEM, TEM, UV/Vis DRS and PL experiments. The results manifest that the reduced graphene oxide (rGO) plays a vital part in transmitting and evacuating electrons, which promotes the separate efficiency of photo‐induced carriers and enhances the photodegradation efficiency of ciprofloxacin. The influences of synthesis conditions were also explored, which cover rGO content, solvent thermal reaction pH, temperature and time. In addition, a feasible photocatalytic mechanism over ciprofloxacin photodegradation under visible light irradiation was proposed. [ABSTRACT FROM AUTHOR]

For exploring the interesting solvent effect on structure and morphology, a variety of MgWO4 nanoparticles were prepared by a one-pot solvothermal method with different proportional solvents of water and ethylene glycol. The results showed that monoclinic wolframite crystalline structure of MgWO4 was successfully synthesized, corresponding to two standard cards of MgWO4 (JCPDS No. 27-0789) and MgWO4 (JCPDS No. 19-0776), respectively. The morphology of MgWO4 nanoparticles presents eight different shapes and orderly transforms from one shape to another with increasing water content in mixed EG-water solvents, and a possible mechanism was proposed. The catalytic activities of these MgWO4 nanoparticles on the thermal decomposition of Ammonium Perchlorate (AP) were compared using differential scanning calorimetry (DSC) method, and found to present good change rule with particle size. The present article encompasses the synthesis of MgWO4 nanoparticles for thermal catalytic decomposition of Ammonium Perchlorate (AP). In the studied materials, MgWO4 nanoparticles were prepared by a one-pot solvothermal method with different proportional solvents of water and ethylene glycol. Owing to the smaller particle size and larger specific surface area of MgWO4 (sample 1#), MgWO4 (sample 1#) prepared in pure EG has the best catalytic performance in the thermal decomposition process of AP. [ABSTRACT FROM AUTHOR]

Indium tin oxide (ITO), a representative transparent conducting oxide (TCO), is widely applied in photoelectric devices. In this work, monodisperse ITO submicro-spheres have been prepared using one-step solvothermal method at 250 °C. l -Histidine (L-His), triethylamine (TEA) and dimethylformamide (DMF) were used as shape controller, base agent and solvent, respectively. Significantly, the effect from process variables on the size and shape of submicro-spheres was studied systematically. L-His was used to promote the formation of spherical morphologies. When reaction time was prolonged from 12 to 24 h, nano-size particles eventually grew into submicron particles. After adding L-His, the size of ITO particles became smaller and the crystal tended to sphere-shape from cubic-shape. Meaningfully, the effect from particle size and morphology plays a key role in the resistivity of resultant powders. Compared with the resistivity of larger particles with mixed morphology prepared without L-His, the one of well-crystallized sphere-shaped small particles prepared with L-His was lower. The range of resistivity was between 0.4 and 0.7 Ω cm when 0.05 M L-His was added. Moreover, uniform spheres with a diameter of 0.29 μm have been obtained by one-step solvothermal method with 1 M TEA and 0.05 M L-His, which have potential application in photonic band gap crystals. [ABSTRACT FROM AUTHOR]

Copyright of Journal of South China Normal University (Natural Science Edition) / Huanan Shifan Daxue Xuebao (Ziran Kexue Ban) is the property of Journal of South China Normal University (Natural Science Edition) Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

For exploring the interesting solvent effect on structure and morphology, a variety of MgWO4 nanoparticles were prepared by a one-pot solvothermal method with different proportional solvents of water and ethylene glycol. The results showed that monoclinic wolframite crystalline structure of MgWO4 was successfully synthesized, corresponding to two standard cards of MgWO4 (JCPDS No. 27-0789) and MgWO4 (JCPDS No. 19-0776), respectively. The morphology of MgWO4 nanoparticles presents eight different shapes and orderly transforms from one shape to another with increasing water content in mixed EG-water solvents, and a possible mechanism was proposed. The catalytic activities of these MgWO4 nanoparticles on the thermal decomposition of Ammonium Perchlorate (AP) were compared using differential scanning calorimetry (DSC) method, and found to present good change rule with particle size. The present article encompasses the synthesis of MgWO4 nanoparticles for thermal catalytic decomposition of Ammonium Perchlorate (AP). In the studied materials, MgWO4 nanoparticles were prepared by a one-pot solvothermal method with different proportional solvents of water and ethylene glycol. Owing to the smaller particle size and larger specific surface area of MgWO4 (sample 1#), MgWO4 (sample 1#) prepared in pure EG has the best catalytic performance in the thermal decomposition process of AP. [ABSTRACT FROM AUTHOR]

LiNi 0.8 Co 0.1 Mn 0.1 O 2 is a promising cathode material for lithium-ion batteries due to its high capacity, high energy density and low cost. However, LiNi 0.8 Co 0.1 Mn 0.1 O 2 suffers from an aggressive side reaction with electrolyte, resulting in poor cycling performance, large polarization and fast voltage degradation. To overcome these drawbacks, we use an acid coprecipitation method to prepare rod-shaped LiNi 0.8 Co 0.1 Mn 0.1 O 2 , and introduce a thin and uniform lithium titanium oxide layer on the surface by a solvothermal method. The 3 mol% lithium titanium oxide-coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 exhibits a much higher capacity retention (88.6%) than the pristine material after 100 cycles, and the polarization and voltage degradation of the Ni-rich cathode are largely alleviated. Furthermore, at an elevated temperature of 65 °C, the capacity retention of lithium titanium oxide–coated LiNi 0.8 Co 0.1 Mn 0.1 O 2 is 81.1% after 50 cycles, which is much higher than that of pristine LiNi 0.8 Co 0.1 Mn 0.1 O 2 (only 52.0%). These results suggest that the surface doping of Ti4+ and the introduction of the lithium titanium oxide layer help to improve the structure stability and mitigate the side reactions on the electrode-electrolyte interface, resulting in good electrochemical performance. • Rod-shape LiNi 0.8 Co 0.1 Mn 0.1 O 2 is synthesized by simple acid co-precipitation. • Uniform and thin layer coating is achieved by solvothermal method. • LiNi 0.8 Co 0.1 Mn 0.1 O 2 with Li-Ti-O coating layer shows improved cycling stability and rate capability. • Polarization and voltage degradation are alleviated by the introduction of Li-Ti-O layer. [ABSTRACT FROM AUTHOR]

• Solvothermal preparation of {001} facets of VOHPO 4.0.5H 2 O in C 2 -C 4 alkanoic alcohols. • Metastable intercalated alkyl-phosphate was only formed when using linear alcohols. • The metastable phase was converted to platy VOHPO 4 ·0.5H 2 O crystallites at 330 °C. • Pseudomorphic {2 0 0} facets of (VO) 2 P 2 O 7 obtained via annealing or in situ activation. • Good ethanol-derived VPO catalyst with larger V5+ amount and thinner crystallites. The catalytic performance of vanadyl pyrophosphate (VPP) catalysts in the oxidation of n -butane to maleic anhydride (MA) depends strongly on the display of the active and selective {0 0 1} faces, that may be controlled during the preparation of VOHPO 4 ·0.5H 2 O precursor by solvothermal technique using C 2 to C 4 alkanoic alcohols. Intercalated metastable vanadyl-alkyl-phosphates were formed when linear alcohols (ethanol, n -butanol) were used, at variance with iso-alcohols. {0 0 1} platelets of VOHPO 4 ·0.5H 2 O yielded {2 0 0} platelets to (VO) 2 P 2 O 7 in nitrogen or in situ in the reactor, as revealed by structural analyses. The catalysts prepared in ethanol or n -butanol in situ activated at 440 °C were more active and selective to MA than in iso-alcohols, but if the equilibration was performed at 380 °C the influence of alcohol was mitigated. The highest MA yield was obtained with the ethanol-derived catalyst, which exhibited the smallest platy crystallites of (VO) 2 P 2 O 7 , as well as surface V5+ species as seen by XPS. [ABSTRACT FROM AUTHOR]

This work presents a study on the synthesis of nanostructure carbon materials by the solvothermal method. Carbon materials with different morphologies, including chain‐like solid carbon particles, hollow carbon nanospheres, and carbon nanoribbons were obtained by adjusting operating conditions. The prepared carbon nanospheres with amorphous structures include amorphous chain‐like solid carbon particles with an average particle size of 118 nm and a length range of 300–600 nm, hollow carbon nanospheres with an average diameter of ∼533 nm, and carbon nanoribbons with an average width of ∼56 nm and a length of 1000–2000 nm. In addition, a possible growth mechanism of nanostructure carbon materials prepared by the solvothermal method was discussed. The research gives a simple route to obtain carbon materials with different morphologies. [ABSTRACT FROM AUTHOR]

The successful application of porous graphene (PG) is hindered due to the lack of efficient and cost-effective method for its synthesis. Herein, we report a facile and eco-friendly method to produce PG through a low temperature solvothermal method. The structural and morphological characteristics of PG samples were investigated thoroughly. The as synthesized material is found to be a few layers thick (∼4–6 layers) with a surface area of 420 m2 g−1 and consisting of hierarchical pores on the surface of the sheets. A high specific capacitance of 666 F g−1 was obtained at a scan rate of 5 mV s−1, apart from longer cyclic stability with 87% retention of initial capacitance value after 10000 cycles for the PG 28 sample. The fabricated supercapacitor displayed an energy density of 26.3 Wh kg−1 and power density of 6120 W kg−1. Density functional theory calculations were also carried out to qualitatively support the enhanced capacitance by providing theoretical insight from electronic structure and density of states of PG. These results open a new avenue for greener synthesis of high-quality PG using environmentally friendly solvents, without the use of toxic chemicals, for excellent supercapacitor performance. Green solvothermal synthesis of porous graphene for supercapacitor applications with a high capacitance value and high cyclic stability. Image 1 • Green solvothermal synthesis of porous graphene for supercapacitor applications. • A high capacitance value of 666 F g−1. • 87% initial capacitance retention after 10000 cycles. [ABSTRACT FROM AUTHOR]

Seven 0D-3D α-Fe 2 O 3 nanostructures with different shapes and sizes have been prepared via a solvothermal route and subsequent calcination. It was found that the dosage of hexamethylenetetramine (HMTA) and the kind of solvent played determinant roles in the controlled synthesis of α-Fe 2 O 3 nanostructures. Increasing the amount of HMTA from 0.070 g to 0.420 g, the morphology of α-Fe 2 O 3 product evolves from 1D nanobelt, 2D nanosheet to 3D nanoflower with sizes ranging from 4 μm to 650 nm. Changing the kind of solvent with various chain lengths or polarity, 0D α-Fe 2 O 3 porous nanospheres, rhombohedra and cylinder microstructure can be obtained. Based on the experimental results, the possible formation mechanism of various dimensional products was speculated. The different gas-sensing behaviors that related with the microstructures of the as-prepared α-Fe 2 O 3 samples were also investigated. The fabricated gas sensors all present good stability and high selectivity towards acetone gas, and the comparable responses to acetone should be due to the variation in their size, morphology and specific surface area (SSA). In addition, the gas-sensing conductive mechanism based on the α-Fe 2 O 3 samples was also proposed. The controlled synthesis of 0D-3D α-Fe 2 O 3 nanostructures using a HMTA-assisted solution approach and their mircostructures-related gas-sensing performance have been reported. Image 1 [ABSTRACT FROM AUTHOR]

In this study, SnS2 nanosheets were successfully synthesized by solvothermal method with SnCl4·5 H2O, thioacetamide as main raw materials, distilled water and absolute ethanol as solvent. Structural and morphological of different samples were characterized by X-ray、scanning electron microscopy（SEM） and transmission electron microscopy（TEM）. The effect of different solvents and ratios on the morphology and electrochemical properties of SnS2 were investigated. The result shows that SnS2 nanosheets(solvent ratio: VC2H5OH:VH2O=2:3) has superior crystallinity and dispersibility, the size of nanosheets significantly reduced. When used as anode for lithium ion batteries, SnS2 nanosheets exhibit a very high initial discharge and charge capacity of 1 504 and 875. 9 mAh·g-1, and can remain a reversible capacity of 370. 04 mAh·g-1 at 100 mA·g-1 after 100 cycles, displaying a superior electrochemical properties. [ABSTRACT FROM AUTHOR]

Olivine-type LiFe x Mn 1- x PO 4 /C cathode materials are of great interest for lithium-ion batteries because of their higher lithium ion intercalation potential compared with that of LiFePO 4. Two types of LiFe 0.5 Mn 0.5 PO 4 /C nanorods with different sizes and crystal structures were synthesized through a facile glycol-based solvothermal process with different precursor feeding sequences. The microstructural investigation revealed that the size and structure of the LiFe 0.5 Mn 0.5 PO 4 nanorods can be tuned by nucleation and crystal growth rates of the intermediate precipitates, which can be controlled by precursor feeding sequence. The LiFe 0.5 Mn 0.5 PO 4 nanorods obtained through the first feeding sequence (a solution of transition metal salts was added dropwise into the solution mixture of LiOH and H 3 PO 4) exhibited less exposure of the (010) crystal faces and had bigger sizes compared with those of the LiFe 0.5 Mn 0.5 PO 4 nanorods obtained through the second feeding sequence (a LiOH solution was added dropwise into the solution mixture of H 3 PO 4 and transition metal salts). Electrochemical investigations indicated that the LiFe 0.5 Mn 0.5 PO 4 nanorods obtained through the second feeding sequence showed substantially improved electrochemical performance, in which the discharge capacities reached 157 and 119 mAh g−1 at 0.2 and 5 C, respectively. Furthermore, a capacity retention of 89% was obtained after 500 cycles at 1 C, demonstrating excellent cyclic stability. Image 1 • LiFe 0.5 Mn 0.5 PO 4 /C nanorods with large exposed (010) faces have been synthesized. • Fast precipitation causes formation of LiFe 0.5 Mn 0.5 PO 4 nanorods with fine sizes. • They show a high cyclic capacity, high stability and high intercalation potential. • Reversible capacity reaches 157 and 119 mAh g−1 at 0.2 and 5 C, respectively. [ABSTRACT FROM AUTHOR]

Highlights • Nickel-cobalt microsphere precursor with mesoporous structure and fine size is synthesized via solvothermal routine. • LiNi 0.88 Co 0.12 O 2 inherits the fine size and particles integrity of nickel-cobalt microsphere precursor. • LiNi 0.88 Co 0.12 O 2 delivers a capacity of 170.5 mAh·g−1 at 4 C after 50 cycles. Abstract At present, the chemical co-precipitation dominates the synthesis pathway of LiNiO 2 -based cathode material for lithium ion batteries (LIBs). Compared with conventional co-precipitation method, advanced functional powder materials synthesized by solvothermal method exhibit fine grain size, higher crystallinity and integrity. In this work, the uniformly dispersed nickel-cobalt microsphere precursor with porous structure and fine size is prepared by solvothermal routine without any template. Subsequently, the LiNi 0.88 Co 0.12 O 2 is synthesized by high-temperature solid-state method. The feasibility of LiNi 0.88 Co 0.12 O 2 as high-performance cathode material for LIBs is explored. As a result, the as-synthesized LiNi 0.88 Co 0.12 O 2 shows excellent high-rate cyclability due to the fine size and particles integrity inherited from nickel-cobalt microsphere precursor. This study reveals that solvothermal routine is a prospective method for synthesizing new formula LiNiO 2 -based cathode material. [ABSTRACT FROM AUTHOR]

The photocatalytic activity of WO3 and C doped WO3 has been monitored by studying the degradation of the methylene blue (MB) aqueous dye solution under visible light irradiation. The photocatalyst WO3 has been synthesized by the solvothermal method and modified by doping carbon into it in the molar ratio 1:1, 1:2, 1:3 and 1:4 under hydrothermal process. The photocatalysts have been characterized for structural and optical properties. XRD has been taken to identify the phase and structure, also confirms the successful incorporation of carbon into WO3 lattice site. Morphology and elemental composition were analyzed using SEM and EDAX. The UV-DRS spectrum showed an increase in absorption intensity with increasing carbon content with decreases in band gap from 3.0 eV to 2.6 eV. PL emission spectra gave blue emission (484 nm) and green emission (555 nm). Finally, the photocatalytic response graph of C doped WO3 with time showed an excellent absorption property and an enhanced visible-light photocatalytic activity compared to pristine WO3. [ABSTRACT FROM AUTHOR]

• The cubic-rhombohedral-In 2 O 3 microflower is assembled by ultrathin nanosheets. • The sensors based on cubic-rhombohedral-In 2 O 3 exhibited a rather low detection limit of 10 ppb to acetone. • The sensor can easily distinguish acetone from the other gases including ethanol. • The extraordinary gas sensing properties are mainly attributed to the unusual n-n heterojunction. Analyzing volatile organic compounds in exhaled breath is a noninvasive method that has potential for disease assessment. Herein, acetone sensors based on porous In 2 O 3 flowers are synthesized through a facile solvothermal method. Structural characterizations demonstrate that the three-dimensional In 2 O 3 flower-like structure comprises porous ultrathin two-dimensional nanosheets. The structural porosity results in a large specific surface area and fast gas diffusion, which can improve the gas sensing performance. The crystalline structure of the prepared hierarchical flower-like In 2 O 3 is a mixed phase of rhombohedral and cubic phases according to the XRD patterns. The sensing properties of the cubic-rhombohedral In 2 O 3 (bcc-rh-In 2 O 3) are also investigated. Compared with commercial-In 2 O 3 -based sensor, the bcc-rh-In 2 O 3 sensor exhibits 2.9 times higher response (Ra/Rg = 12) and shorter response time (ca. 2 s) toward 50 ppm acetone. The bcc-rh-In 2 O 3 sensor has a low detection limit of 10 ppb in atmosphere and can easily distinguish acetone from ethanol. The extraordinary properties of the bcc-rh-In 2 O 3 sensor are mainly attributed to the n-n heterojunction between rh-In 2 O 3 and bcc-In 2 O 3. [ABSTRACT FROM AUTHOR]

In this study, lithium terephthalate by solvothermal method with low energy consumption and simple preparation process were synthesized. To obtain the lithium terephthalate with best electrochemical properties, the effects of different organic solvents, reaction temperature and lithium source were investigated and compared. The electrochemical performance of lithium terephthalate prepared from various processing methods as lithium ion battery was furtherly analyzed and discussed. The compositions lithium terephthalate of were confirmed by XRD and FTIR, the morphologies were observed by SEM, and the electrochemical properties were analyzed by cycle charge-discharge tests. The results show that the first discharge capacity of the battery prepared by lithium hydroxide in DMF at a reaction temperature of 175 °C presented the best performance, reaching a maximum capacity of 235/74 mA⋅h/g. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metal Materials & Engineering is the property of Northwest Institute for Nonferrous Metal Research and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A facile and convenient approach was proposed to highly fill carbon nanotubes with various nanoparticles, such as Fe3O4 and CoO. Furthermore, in the case of Fe3O4 and CoO nanoparticles, the effect of reaction conditions on the filling quality and confinement of CNTs on the size and morphology of NPs were explored. The encapsulation procedure in our work can provide a valuable guidance for filling a variety of NPs into hollow structure apart from CNTs. In addition, as a proof-of-concept demonstration, the magnetic properties of Fe3O4 in the absence and presence of CNTs were measured to indicate that magnetization and the blocking temperature of superparamagnetic Fe3O4 can be adjusted, which is due to the confinement effect of CNTs. [ABSTRACT FROM AUTHOR]

Abstract Heterostructure MoS 2 nanosheets decorated CdS nanoparticles were successfully prepared by a facile two-step solvothermal method. The growth of ultrathin MoS 2 nanosheets on CdS surface in terms of thickness and interlayers of (002) MoS 2 was controlled by changing solvothermal reaction temperature. A series of MoS 2 nanosheets decorated CdS nanoparticles were prepared at different temperature. The synthesized composites were characterized with XRD, FESEM, TEM, UV–vis DRS, BET, PL, XPS, EPR and I-T. TEM observations revealed the growth of ultrathin MoS 2 nanosheets over the CdS nanoparticles, the thickness of MoS 2 sheets and interlayers distance of (002) in composite was found to decrease with increasing the reaction temperature to 220 °C, under the same conditions. Photocatalytic activities of the as-prepared MoS 2 /CdS nanocomposites for the MO degradation were evaluated under the visible light irradiation. The ultrathin MoS 2 /CdS nanocomposites 1–220 with thinner sheets prepared at 220 °C exhibits higher photocatalytic efficiency for degradation of MO under visible light than all the other synthesized samples at different temperature. Furthermore, it was found that this catalyst retains remarkable photocatalytic activity after five cycles. The PL spectrum and photocurrent responses results suggest that the MoS 2 /CdS nanocomposite 1–220 possess higher separation efficiency and minimum recombination of photo-generated electrons and holes than pure CdS. The photocatalytic degradation mechanism of the MO over MoS 2 /CdS nanocomposite was proposed. Graphical abstract Enhanced visible-light photocatalytic degradation MO with high stability could be achieved over the nanocomposite ultrathin nanosheets MoS 2 on CdS nanoparticles with narrow band gap structure. Unlabelled Image Highlights • Ultrathin nanosheets of MoS 2 on CdS nanoparticles were successfully synthesized. • The thicknesses and interlayers distance (002) of MoS 2 on CdS nanoparticles were controlled. • MoS 2 /CdS nanocomposite 1–220, exhibits high photocatalytic activity under visible light. • Photo-generated electrons transferred from CdS to MoS 2 nanosheets [ABSTRACT FROM AUTHOR]

Single-phase chalcopyrite CIGS particles with the sizes of 40–60 nm and the stoichiometry of Cu 26.01 (In 17.00 Ga 8.01)Se 48.98 were synthesized by the solvothermal method. The CIGS precursor layers were prepared via the doctor-blade coating process utilizing the slurry containing CIGS nanoparticles and the CIGS layers were then formed by a selenization at 540 °C for various times in the Se vapor ambient. Microstructure and composition analyses indicated the CIGS layers are of the singe-phase chalcopyrite phase and the Cu-poor composition feature with stoichiometry close to the ideal ratio of 1:1:2. Moreover, the increase of selenization time benefited the coarsening of grain structure in CIGS layer as revealed by the scanning electron microscopy. Accordingly, the CIGS thin-film solar cell samples with the Mo/CIGS/CdS/ i -ZnO/AZO/Ag structure were prepared and their performance were evaluated. Under the AM1.5 illumination condition, the best PV performance with open-circuit voltage of 0.49 V, short-circuit current density of 29.46 mA/cm2, fill factor of 54% and conversion efficiency of 7.75% was accomplished in the thin-film solar cell sample containing CIGS light absorption layer prepared by the 540°C-selenization for 15 min. • CIGS nanoparticles with the size of 40–60 nm was synthesized by solvethermal method. • Slurry containing CIGS nanoparticles was prepared for doctor-blade coating process. • CIGS layer was prepared by doctor-blade coating process followed by Se-vapor selenization. • CIGS thin-film solar cell with conversion efficiency of 7.75% was achieved. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Dispersed WO 3 nanoparticles with high crystallinity, well dispersity and porous nanostructure were successfully synthesized through adjusting hexamethylenetetramine (HMT) amount and subsequent annealing treatment. • The sensor based on dispersed WO 3 nanoparticles sintered at 500 °C possesses the highest response (132.0) towards 100 ppm toluene at the operation temperature of 225 °C. • The sensor also exhibits not only a good selectivity for toluene among various VOC gases but also ultrafast response/recovery time (2 s/6 s) to 100 ppm toluene at the optimal working temperature. • The obtained superior gas sensing properties can be attributed to the high resistance caused by crystallinity and grain boundary, and porous structure of the sensing materials. Abstract The preparation of size-controlled materials has shown remarkable potential with regard to their reinforced sensing performance. Herein, we report a facile solvothermal synthesis of dispersed WO 3 nanoparticles with porous nanostructure caused by particle assembly. Various characterizations of the as-obtained samples were analyzed. Furthermore, the gas sensing properties of WO 3 samples on volatile organic compounds were investigated. The results reveal that the gas sensors based on synthesized WO 3 samples with suitable hexamethylenetetramine (HMT) amount and sintering treatment exhibit the highest response (132.0) towards 100 ppm toluene at the optimal working temperature of 225 °C with fast response/recovery time (2 s/6 s), which is attributed to the porous structure of the sensing film and the high resistance caused by well crystallization and grain boundary among the nanoparticles. [ABSTRACT FROM AUTHOR]

Pure and Co-doped CeO 2 nanoparticles were synthesized successfully by the solvothermal method. The effect of Co substitution and external magnetic field on the morphologies and magnetic properties of nanoparticles was investigated. Results showed that synthesized Co-doped CeO 2 had the face-centered cubic structure and no other impurities existed in the samples with the increase of Co concentration from 5 to 75 wt%. The increasing Co concentration made the morphologies of Co-doped CeO 2 nanoparticles vary from the hollow sphere, solid sphere to rod-like shape. The applied external magnetic field of 5T decreased the nanoparticle size effectively including the diameter of hollow sphere with low Co concentration and rod-like particles with high Co concentration. Moreover, the wall thickness of hollow sphere particles was also decreased from 35 nm to 18 nm for pure CeO 2. The Co-doped CeO 2 nanoparticles showed the weak ferromagnetic behavior. With the increase of Co concentration, the saturation magnetization (M s) value increased first and then decreased. The Co-doped CeO 2 with 30 wt% showed the highest value of 3.65 × 10−2 emu/g (M s). The M s value of Co-doped CeO 2 prepared in 5T showed an increasing trend with the Co concentration. The highest value (M s) reached 4.21 × 10−2 emu/g for doped CeO 2 with 75 wt% Co. [ABSTRACT FROM AUTHOR]

Abstract To obtain high-performance lithium-ion capacitors (LICs), superior Fe 3 O 4 /reduced graphene oxide (rGO) composite has been synthesized by a facile one-step solvothermal method. The morphologies and structures of materials were characterized by powder X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy and N 2 adsorption–desorption isotherm. Electrochemical performances of materials were evaluated by cyclic voltammetry, galvanostatic charge/discharge and electrochemical impedance spectroscopy in half cell. Compared with the agglomerated pure Fe 3 O 4 , the high-crystallinity Fe 3 O 4 particles uniformly distributes onto the rGO sheets and the Fe 3 O 4 particles possess smaller size of 150–250 nm in Fe 3 O 4 /rGO composite. Therefore, the introduction of rGO can not only increase the specific surface area but also enhance the electrical conductivity of electrode material, leading to the improvement of electrochemical performances. The Fe 3 O 4 /rGO composite can reach high specific capacity of 1065 mAh g−1 at 0.1 A g−1, and exhibits good rate capability and cyclic stability. Using the as-prepared Fe 3 O 4 /rGO composite as negative electrode and activated carbon (AC) as positive electrode, a Fe 3 O 4 /rGO//AC LIC was fabricated. The assembled Fe 3 O 4 /rGO//AC LIC presents outstanding energy density of 98.8 Wh kg−1 and power density of 3.4 kW kg−1. Moreover, 78.9% of capacity can be retained after 1000 charge/discharge cycles. Highlights • Fe 3 O 4 /rGO composite is prepared by a one-step solvothermal method. • Fe 3 O 4 /rGO composite can reach high specific capacity. • A Li-ion capacitor is assembled by using Fe 3 O 4 /rGO composite as negative electrode. • The Li-ion capacitor shows high energy density. [ABSTRACT FROM AUTHOR]

Preparation of semiconductor nanomaterials with controlled morphology and uniform porous surface is of great interest for enhanced photocatalytic applications. In the work presented herein, uniform sphere-like niobium pentoxide (Nb2O5) nanostructures were synthesized by a one-pot solvothermal method using ammonium niobate oxalate and octadecylamine as precursor and surfactant, respectively. The synthesized Nb2O5 nanostructures were then employed as photocatalyst for degradation of methylene blue (MB) and rose bengal (RB) dyes under ultraviolet (UV) light. It was found that the prepared Nb2O5 nanostructures could degrade up to 87 % and 62 % of MB and RB dye after irradiation for 90 and 180 min, respectively. [ABSTRACT FROM AUTHOR]

For the first time, a series of flower-like CuS/UiO-66 composites with different UiO-66 contents were fabricated via a facile solvothermal method. The as-prepared composites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), UV–vis optical absorption spectroscopy and photoluminescence (PL) spectra. The CuS/UiO-66 composites exhibited remarkable performance for the degradation of Rhodamine B (RhB) as compared to pure UiO-66 under visible-light irradiation. Moreover, the catalytic activity was related to the weight ratio of CuS to UiO-66 in the composites, and the CuS/UiO-66 (weight ratio 2.4:1) composites exhibited the highest photocatalytic activities. The improved photocatalytic activity contributed to the synergetic effect between CuS and UiO-66, which facilitated the separation efficiency of photogenerated electron-hole pairs. The possible mechanism of the enhanced photocatalytic performance of the CuS/UiO-66 composites was also discussed. This work demonstrates that the CuS/UiO-66 composite is a promising photocatalyst for removing of organic pollutants. Unlabelled Image • A series of flower-like CuS/UiO-66 composites were prepared. • The CuS/UiO-66 composites exhibited remarkable performance for the degradation of RhB. • The enhanced photocatalytic performance was attributed to the synergistic effect of CuS and UiO-66. [ABSTRACT FROM AUTHOR]

In this study, Fe-, Ce-, and La-doped TiO 2 ultrafine nanospheres were synthesized via low-temperature solvothermal method. The structural and morphological variations of bare and M (Fe, Ce, La)- doped TiO 2 were confirmed by X-ray photoelectron spectroscopy and transmission electron microscopy images. The fabricated photoanodes were tested using 1 M KOH electrolyte and demonstrated that they can be used for eco-friendly photoelectrochemical solar water-splitting application. Compared to bare TiO 2 photoanodes, foreign cations (Fe, Ce, La)-doped TiO 2 -based photoanodes exhibited higher photocurrent response without bias. In nutshell, the rare-earth element La-doped TiO 2 nanosphere photoanode showed good photocurrent response to approximately 0.48 mA/cm2 under illumination, with lower flat band potential shift of −0.83 V. The highest photostability of 96% was achieved over 2 h for 10% La-doped TiO 2 nanosphere photoanode and was suitable for solar water-splitting applications. • Highest photostability of 96% is achieved over 2 h for 10% La-doped TiO 2. • 10% La-doped TiO 2 nanospheres showed highest photocurrent response of 0.48 mA/cm2. • Lowest flat band potential of around −0.83 V with the negative shift was obtained. • Highest photostability over 7200 s with 96% of retention under irradiation [ABSTRACT FROM AUTHOR]

Ultra-long hydroxyapatite (HAP) nanowires have been hydrothermally synthesised using calcium chloride and phosphate sodium as the starting materials, and then, an antimicrobial bioceramics is successfully fabricated using the HAP-based ceramics by a simple interfacial ZnO adhesion procedure. The bioceramics is characterised by X-ray powder diffraction, scanning electron microscopy, and Fourier-transform infrared spectroscopy. The effect of the concentration of alkaline on the crystal phase and morphology of the HAP nanowires as well as sintering temperature on the crystal phase and morphology of the as-prepared bioceramics is investigated. Antimicrobial properties of the bioceramics are also carefully examined. The results show that the length-to-diameter ratio of the HAP nanowires can be well monitored by the alkalinity, and the ZnO@HAP bioceramics exhibited excellent antibacterial activity. Its antibacterial activity can be well controlled by ZnO nanoparticle content packed in the interspace of the ZnO@HAP bioceramics with different porosities obtained at different temperatures. [ABSTRACT FROM AUTHOR]

As a direct bandgap semiconductor, organic-inorganic lead halide perovskite (MAPbX 3 , MA = CH 3 NH 3 , X = Cl, Br, I) have been considered as promising materials for laser due to their excellent optoelectronic properties. The perovskite materials with 1D and 2D shapes were widely prepared and studied for Fabry-Pérot mode and whispering-gallery-mode (WGM) microcavities, but cuboid-shape is rarely reported. In this work, we successfully fabricated single crystal cuboid-shaped MAPbBr 3 perovskite with different morphologies, named microcuboid-MAPbBr 3 (M-MAPbBr 3) and multi-step-MAPbBr 3 (MS-MAPbBr 3), via solvothermal method. Furthermore, the as-prepared crystals' excitonic recombination lifetime under different pumping energy density was studied by time-resolved photoluminescence (TRPL). Based on controllable morphology and remarkable lasing properties, these cuboid shaped single crystal perovskite could be a promising candidate for small laser, and other optoelectronic devices. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Pt-based nanocomposites with low Pt utilization and high-activity by incorporating with other transition metals have received significant interest in catalysis. Meanwhile, loading Pt-based catalysts on graphene has great research value for improved stability and dispersity of the catalysts. Herein, a facile l -proline-mediated solvothermal strategy was reported to construct reduced graphene oxide (rGO) supported sheet-like PtCo nanocrystals (Pt 78 Co 22 NCs/rGO) in ethylene glycol (EG). The as-synthesized nanocomposite manifested remarkably improved catalytic properties and chemical stability for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER), surpassing home-made Pt 29 Co 71 nanoparticles (NPs)/rGO, Pt 83 Co 17 NPs/rGO, Pt 52 Co 48 NPs, commercial Pt/C and Pt black catalysts. These scenarios demonstrated an improved catalytic performances by tailoring the feeding ratio of Pt:Co and introducing rGO as a support. This work provides some new insights to design rGO-supported Pt-based catalysts by engineering the shapes and compositions in practical fuel cells. [ABSTRACT FROM AUTHOR]

Nanosized ZnO with a special three-dimensional (3D) structure was prepared by a solvothermal method using carbamide as the precipitant and then an ZnO-based ethanol gas sensitive material was obtained successfully by changing the doping amount of Ag. The phase structure and microstructure of the obtained products were characterized by XRD and SEM and the gas sensing property was tested using the static volumetric method. The results show that the gas sensing performance of 3D ZnO-based ethanol can improve effectively by doping Ag， in comparison with pure 3D-ZnO. When the amount of doping Ag is 1.5% and the volume fraction of ethanol is 0.1%， the value of gas sensor is up to 31.61， the operating temperature decreases from 350℃ to 200℃ and the response/recovery time are shorted to 10s/10s. Meanwhile， the selectivity to ethanol gas is enhanced. [ABSTRACT FROM AUTHOR]

Abstract As a promising thermoelectric material, copper selenides have attracted the interest of researchers owing to their low cost, abundance in earth, environmental friendliness, and low thermal conductivity. In this study, copper selenide (Cu 2-x Se) powders with controllable sizes from nanoscale to mesoscale were obtained by a facile one-pot solvothermal method. After treatment with spark plasma sintering, the nanoscale Cu 2-x Se pellets exhibited excellent thermoelectric properties such as sharply reduced thermal conductivity and enhanced Seebeck coefficient as well as a suppressed electrical conductivity. The figure of merit (ZT) of the nanoscale Cu 2-x Se reached up to ∼1.51 at 873 K, which is about 2.67 times higher than that of the meso-Cu 2-x Se. This study confirms that thermoelectric properties can be enhanced by the size effect. [ABSTRACT FROM AUTHOR]

Low cost earth abundant absorber materials are set to play a major role in future generation thin film solar cell technologies. Here, we have utilized a facile approach of dissolving elemental precursors, viz copper, tin and selenium, to synthesize earth abundant Cu2SnSe3 (CTSe) nano-crystals using the solvothermal method. All the metallic precursors were made to react with a mixture of thioglycolic acid and methylamine, and the reactants were dissolved in three different solvents—distilled water, ethylene glycol and oleic acid. The influence of the solvents on the structural, morphological and optical properties of the nano-crystalline CTSe particles was studied. X-ray diffraction and Raman studies reveal that the CTSe nanocrystals grow in the cubic phase with a lattice parameter ∼ 5.6 Å. FESEM results reveal different morphologies including nanoflakes and nano-particles depending on the solvent. Selected area electron diffraction patterns confirm the crystalline nature of the products. Optical properties show that the optical gap of the nanocrystals is around 1.32–1.45 eV, which is in the band gap range reported in the literature and is optimum for solar cell applications. The photocatalytic activity of the CTSe nanocrystals was demonstrated by using the material for the degradation of methylene blue dye in the presence of UV–visible light. The results confirm that the CTSe nanocrystals exhibit good photocatalytic response, the best activity being seen in samples grown from water. [ABSTRACT FROM AUTHOR]

Highlights • Porous MgCo 2 O 4 assembled by secondary ultrafine nanoparticles are fabricated. • The porous structure promotes the infiltration of electrolyte and MgCo 2 O 4. • The MgCo 2 O 4 electrode shows excellent cycling performance and rate capability. • The capacity stabilizes at 543 mAh g−1 after 350 cycles at 2000 mA g−1. Abstract In this paper, we developed a solvothermal method and subsequent heat treatment route to synthesize a novel porous structure of MgCo 2 O 4 assembled by secondary ultrafine nanoparticles. Such a porous structure can effectively promote the infiltration of electrolyte and MgCo 2 O 4 nanoparticles, thus increasing the electrochemical reaction sites of the MgCo 2 O 4 electrode during the charge/discharge process. Correspondingly, when tested as anode materials for Lithium ion batteries, the porous MgCo 2 O 4 electrode delivered a high specific capacity of 824 mAh g−1 after 150 cycles at a current density of 500 mA g−1. Even at the high current density of 2000 mA g−1, a reversible capacity of 543 mAh g−1 can be achieved after 350 cycles showing excellent cycle stability. Hence, the porous network architecture MgCo 2 O 4 is promising electrode materials for Lithium ion battery applications. [ABSTRACT FROM AUTHOR]

Silver nanowires(AgNWs)are good for conductive ink and flexible transparent conductive film, due to its high transmittance and good conductivity. The performance of silver nanowires with small diameter and high aspect ratio is better than that of silver nanowires, therefore it is necessary to discuss the preparation process and technology. In this paper, a simple solvent thermal method was used for the preparation of small diameter and homogeneous silver nanowires, using silver nitrate as a silver source, ethylene glycol(EG)as a reducing agent, polyvinylpyrrolidone(PVP)as a growth agent, and hexahydrated nickel chloride(NiCl2·6 H2O)as a control agent. The effects of reaction time, concentration of nickel chloride and PVP/AgNO3 molar ratio on the microstructure of silver nanowires were investigated. It was found that silver nanowires with smallest diameter(25~35 nm)and highest aspect ratio(1 000)were prepared when the concentration of NiCl2 was 200μmol/L, reaction time was 10 h, and PVP/AgNO3 molar ratio was 2. [ABSTRACT FROM AUTHOR]

Abstract Acidic catalysts dedicated for esterification processes were prepared by immobilization of (3-mercaptopropyl)trimethoxysilane (MPTMS) on mesoporous silica and niobiosilicate material using a new methodology, i.e. solvothermal technique with increased pressure. The structure and surface properties of the samples obtained were examined using N 2 adsorption/desorption, XRD, TEM, XPS and elemental analysis. The impact of modification technique as well as the presence of niobium in the sample on the acidity of final materials was investigated. It was found that the application of external pressure during the solvothermal modification of mesoporous silica with MPTMS allows obtaining materials with a greater number of acidic sites. These samples showed a high activity and stability in esterification of acetic and propionic acid with n-butanol and n-hexanol. Graphical abstract Image 1 Highlights • Increased pressure during solvothermal modification of SBA-15 was applied. • Materials with a higher concentration of acid sites were obtained. • This methodology could be extended over preparation of other materials. • Catalysts show a high activity and stability in esterification processes. [ABSTRACT FROM AUTHOR]

Abstract In this paper, a method combining hydrolysis of tetrabutyl orthotitanate (TBOT) and solvothermal reaction was first used to fabricate nanostructured Li 2 TiO 3 tritium breeder ceramic pebbles. Initially, superfine nanostructured Li 2 TiO 3 powders were synthesized with average particle size of about 10 nm, according to TEM. The surface area of precursor particles synthesized via this method was found to be 115.85 m2/g by BET analysis, which is much larger than that of the product obtained using traditional methods. The results showed that precursor particles had high sintering activity. XRD pattern revealed that the phase transition temperature for monoclinic phase Li 2 TiO 3 prepared by this method was nearly 450 °C, which was the lowest phase transition temperature reported among all wet chemical methods to date. Subsequently, investigation of ceramic sintering demonstrated that Li 2 TiO 3 ceramic pebbles with desired nano-crystalline sizes (27.98 ~ 55.03 nm) were obtained by sintering at 500 ~ 600 °C for 4 h. The possible mechanisms were proposed based on the reaction processes of TBOT hydrolysis, solvothermal reaction and sintering. [ABSTRACT FROM AUTHOR]

VPO catalysts supported on silicon carbide were prepared using the solvothermal method. A decrease the reaction temperature by 70 °C under application of SiC, prepared from sucrose and fumed silica, as a support for an active VPO phase compared to a bulk VPO catalyst prepared under similar synthesis conditions was demonstrated. A twofold increase of the productivity towards maleic anhydride was reached. The higher specific reaction rate of n-butane oxidation over prepared supported VPO-SiC systems compared to the bulk VPO catalyst was shown. Use of an environmentally safe support allowed to reduce an amount of active vanadium-containing phase, and an application of the solvothermal method decreased the synthesis duration and an amount of organic solvent compared to the traditional approaches to the synthesis of VPO systems. [ABSTRACT FROM AUTHOR]

Abstract Macaroon-like FeCo 2 O 4 nanomaterial was prepared and used as electrocatalyst in direct glucose alkaline fuel cell (DGAFC), which exhibited high catalytic activity towards glucose oxidation reaction. Maximum power density of 35.91 W m−2 was achieved in the DGAFC equipped with a FeCo 2 O 4 modified activated carbon (AC) anode, which was almost 151% higher than the control. Physical and electrochemical characterizations were performed to provide further understanding of the origin of its high activity. Our results show that the introduction of FeCo 2 O 4 into the AC anode remarkably increase the exchange current density and reduce the charge transfer resistance. It is supposed that there is a synergistic effect between Fe (III) and Co (III), which accelerates electron transfer from glucose to external circuits. This study will promote the development of cost effective and environmentally benign catalysts for electrochemical energy applications. Graphical abstract Image 1 Highlights • Macaroon-like FeCo 2 O 4 was prepared by a simple solvothermal method. • FeCo 2 O 4 modified activated carbon anode demonstrated high performance. • The catalytic mechanism for glucose oxidation by FeCo 2 O 4 was proposed. • The highest peak power density of 35.91 W m−2 was achieved. [ABSTRACT FROM AUTHOR]

Abstract The three-dimensional (3D) nickel-cobalt double hydroxides nanosheets in situ grown on nitrogen-containing activated carbon (NAC/NiCo-DHs) were obtained via a simple solvothermal method. The NAC activated by low-cost green calcium chloride as a substrate greatly enhances the conductivity and specific surface area of the materials, and the unique sheet structure of NAC/NiCo-DHs facilitates the transport of charges. The electrochemical test results show that NAC/NiCo-DHs have a high specific capacitance of 1920 F g−1 at 1 A g−1, outstanding high-rate capability, with 85.4% retention after a 20-fold increase in current densities, and excellent cycling stability with 95.54% specific capacitance retained after 1000 cycles at 20 A g−1, and even after 2000 cycles, the capacitance retention rate of the material can still reach 71.37%. In addition, NAC/NiCo-DHs//AC device exhibits a maximum energy density and power density of 54.8 Wh kg−1 and 8000 W kg−1, and a remarkable cycling stability with 81.86% retention level after 2500 cycles at 5 A g−1, indicating that it has great potential as an energy storage device. Highlights • The porous NAC was prepared by simple method of calcium chloride activation. • The 3D NiCo-DHs nanosheets in situ grown on NAC was designed. • NAC/NiCo-DHs with a large specific surface area exhibited excellent rate performance. • The highest energy density of NAC/NiCo-DHs//AC device reached 54.8 Wh kg−1. [ABSTRACT FROM AUTHOR]

Abstract During the charge-discharge of the LiNi 0.5 Mn 1.5 O 4 (LNMO) cathode in Li-ion batteries, Ni2+ and Mn2+ dissolve in the electrolyte to cause oxidative decomposition, which is the major cause for fast capacity fading and poor cycle performance. Reducing the direct contact area between the cathode material and the electrolyte is a direct solution to improve the cell performance. This paper focuses on a solvothermal method to coat the surface of LiNi 0.5 Mn 1.5 O 4 hollow microspheres with TiO 2 followed by TiO 2 conversion into Li 4 Ti 5 O 12 (LTO) using LiOH·H 2 O. The Li 4 Ti 5 O 12 coating layer synthesized by this method demonstrates epitaxial growth on the outer surface of LiNi 0.5 Mn 1.5 O 4. The LTO-coated LNMO cathode exhibits capacity retention of 88.1% after 100 cycles at 0.5C rate, much higher than 62.2% for the bare LNMO counterpart, at elevated temperature of 55 °C. In addition, the Li+-ion mobility for the LTO-coated LNMO electrode is increased. Highlights • Li 4 Ti 5 O 12 is coated on LiNi 0.5 Mn 1.5 O 4 hollow microspheres via a solvothermal method. • Epitaxial growth of Li 4 Ti 5 O 12 on LiNi 0.5 Mn 1.5 O 4 surface is achieved. • Li 4 Ti 5 O 12 coated LiNi 0.5 Mn 1.5 O 4 is conducive to the electrochemical performance improvement. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract It is a great challenge to develop simple approach to construct three-dimensional (3D) bimetallic alloyed nanoframes (NFs) with tunable surface structures, albeit with the availability of noble metal NFs in catalysis. Herein, a one-pot solvothermal method was employed for scalable preparation of uniform hollow PtCu rhombic dodecahedron nanoframes (PtCu RDNFs) in the presence of cetyltrimethylammonium chloride (CTAC), where diglycolamine (DGA) served as the co-reductant and co-structure director. The above architectures had the larger electrochemically active surface area (ECSA, 36.85 m2 g−1 Pt) than that of commercial Pt black (15.85 m2 g−1 Pt), along with the improved catalytic characters for hydrogen evolution reaction (HER) and oxygen reduction reaction (ORR) in acid electrolytes alternative to those of Pt black. It demonstrates great potential applications of PtCu RDNFs in fuel cells and beyond. [ABSTRACT FROM AUTHOR]

In this paper, we prepared mesoporous nickel cobaltite (NiCo2O4) nanostructures with multi-morphologies by simple solvothermal and subsequent heat treatment. By adjusting the solvent type, mesoporous NiCo2O4 nanoparticles, nanorods, nanowires, and microspheres were easily prepared. The as-prepared products were systematically characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and Brunauer–Emmett–Teller (BET) method. Furthermore, the catalytic activities towards the thermal decomposition of ammonium perchlorate (AP) of as-prepared NiCo2O4 nanostructures were investigated. [ABSTRACT FROM AUTHOR]

Simple solvothermal method was used to synthesize of uniform silver nanowires with the controllable diameter (17, 20, 35, 70 and 100 nm). It is the first report on the solvothermal synthesis of ultra‐thin silver nanowires (17 nm) with the high aspect ratio (>1000). Knowing silver nanowires diameter, length and yield after synthesis are a critical step to classify them for the final goal. Up to now, although the length of nanowires can be measured with the optical microscope, but to estimate the diameter, costly high‐resolution microscopic techniques are necessary. Herein, UV/Vis spectroscopy as an easy and cost‐effective tool is introduced to evaluate the diameter and yield of nanowires. For this purpose, after synthesis and purification of silver different nanowires; from their UV/Vis spectra, a new equation for evaluation nanowires diameter was extracted. In addition, for the first time, absorption coefficients (ϵ) of nanowires with different diameter thickness were reported and a new equation to estimate absorption coefficients to calculate concentration (mg/ml) and yield of silver nanowires was extracted. These equations have good agreement with real data and are independent of the length of nanowires. UV/Vis spectroscopy can be used to estimate the diameter, concentration and yield of silver nanowires suspensions. It is simple, fast and cost effective tool that can be replaced with expensive high resolution SEM and TEM microscopic techniques that are not available in most research laboratories. [ABSTRACT FROM AUTHOR]

In combination of a facile and scalable solvothermal method and solid-phase reduction reactions, a novel two-dimensional black TiO2 − x nanosheet (TiO2 − x NS) with high specific surface area of 108 m2 g−1 and nearly total solar spectral absorption capability have been successfully prepared. With careful characterizations, the novel TiO2 − x NS showed enhanced electrochemical performance and visible-light photocatalytic activity than those of their white TiO2 nanosheet (TiO2 NS) precursors. The black TiO2 − x NS electrode delivered a reversible specific capacity of 160 mA h g−1 even after cycling at 0.5 C (1 C = 190 mA h g−1) for 300 times, which was significantly higher than the corresponding white TiO2 NS electrode (104 mA h g−1). Meanwhile, the TiO2 − x NS also exhibited enhanced ability of visible-light photocatalytic hydrogen production than that of the white TiO2 NS. It is expected that making white TiO2 NS into black ones is an effective way to design the photocatalysts with visible light response and the anodes with long lifetime and high rate performance in lithium ion batteries. The novel black TiO2 − x NS could find potential applications in the field of environmental management and energy storage and conversion. [ABSTRACT FROM AUTHOR]

Abstract In this regard for the first time, the multicomponent chalcogenide Cu2(Zn1-xCrx)SnS4 (CZCrTS) nanocrystals at (0 ≤x ≤ 1) were synthesized by the solvothermal method. Improvement of structural, optical and electrical properties in Cr-doped Cu 2 ZnSnS 4 thin film deposited on SLG substrate by spin coating technique has been investigated. It was observed that introduced the Cr element into the Cu 2 ZnSnS 4 nanocrystal led to increasing the disorder of cations distribution within the unit cell through increasing the tensile strain inside the unit cell resulting in a decline the unit cell volume accompanied by a decrease the particle size and also the crystallite size. It has been found that the optical band gap of the CZCrTS nanocrystals ranges from 1.54 to 1.35 eV with increasing the partial substitution of Zn element with Cr element which in turn also led to a significant improvement in the crystallinity of the Cu2ZnSnS4 film, a facilitates the grain growth and also increases the grain size where accompanied this process post-sulfurization at 450 ℃ for 30 min. In addition, it was observed that the number of grains in the Cu2CrSnS4 film (x = 1), 2.79 (nm−2), were lower than that, 6.8 (nm−2) of the Cu2ZnSnS4 film. Also, the dislocation density in the Cu2CrSnS4 film (x = 1), 0.012 (nm−2), was lower than that, 0.024 (nm−2) of the Cu2ZnSnS4 film, which resulted in decreased the defects in the grain boundaries and increasing the current from 0.34 mA for the Cu2ZnSnS4 film to 0.42 mA for the Cu2CrSnS4 film. Due to a higher absorption coefficient (>104 cm−1), a higher optical conductivity (> 23 *1012 S−1) and lower transmittance have been reported for the Cu 2 CrSnS 4 thin film (x = 1), we believe the Cu2CrSnS4 thin film may be a good candidate can be used as an absorbent layer to sunlight in thin film solar cell. [ABSTRACT FROM AUTHOR]

Abstract LiMnPO 4 /C with hierarchical spindle structures was synthesized by a facile solvothermal method at 180 ℃ for 10 h. The morphology and structure of the prepared materials were controlled through the adjustment of hexamethylenetetramine (HMT). The synthesized materials were investigated by means of X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Quantachrome instrument(Quabrasorb SI-3MP) and Fourier transform infrared spectroscopy (FTIR), and so on. The prepared LiMnPO 4 /C exhibits good electrochemical performance, for instance, there are 153.2, 126.3, 110.2 mA h g−1 at 0.05 C, 1 C, 2 C respectively. The promising properties of the materials results from unique hierarchical nanostructures and the uniform thin carbon coating of particle surface, which improve the ionic and electronic transfer of LiMnPO 4. [ABSTRACT FROM AUTHOR]

Abstract Among various carbon materials, nitrogen doped single walled carbon nanohorns (N-SWCNHs) have a unique structure of clustered conical cages (2–5 nm in diameter and 40–50 nm in length) arranged in dahlia, bud and seed-like configurations. Each conical cage has five pentagons at their tips which act as potential reactive site with their own distinct chemistry. We exploited these reactive sites of N-SWCNHs by preferentially growing germanium nanocrystals (Ge NCs) onto their conical tips using oleylamine as a mild reducing agent. Therefore, Ge decorated N-SWCNHs (Ge@N-SWCNHs) composite was used, for the first time, as active anode material for lithium ion batteries providing high and stable capacity of 1285 mAh/g at 0.1C after 100 cycles. Our results show that preferential growth of Ge Nanocrystals (NCs) on the tips of N-SWCNHs not only allows high utilization of active material but prevents the aggregation of Ge NCs after multiple cycling. Finally, we highlight the potential role of N-SWCNHs as cheap and industrially scalable conductive host for next generation lithium ion batteries. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract In this report for the first time, the Cu 2 Zn 1-x Bi x SnS 4 (CZBiTS) semiconductor at (0 ≤ x ≤ 1) has been synthesized using the solvothermal and spin coating methods. The structural, optical, morphological and electrical properties of CZBiTS semiconductor were investigated. It was found that the Cu 2 BiSnS 4 (x = 1) (CBiTS) thin film was better than the Cu 2 ZnSnS 4 (x = 0) (CZTS) and CZBiTS (x = 0.25, 0.5 and 0.75) thin films due to its optimum features like higher absorption coefficient (>104 cm−1), higher optical conductivity, lower transmittance and lower band gap (1.25 eV). Furthermore, the CBiTS thin film was more uniform, improved and had large grains so; it was observed the number of grains in the CBiTS film, 0.038 nm−2, were lower than that, 6.8 nm−2 of the CZTS film. Also, the dislocation density in the CBiTS film, 0.0007 nm−2, was lower than that, 0.024 nm−2 of the CZTS film resulting in decreasing the defects in the grain boundaries and increasing the current from 0.34 mA for the CZTS film to 0.48 mA for the CBiTS film. Based on the observed results, authors considered the CBiTS thin film as a novel material and competitor for the CZTS thin film and can be used as an absorbent layer to sunlight in thin film solar cell. [ABSTRACT FROM AUTHOR]

A nanocube is a single nanoscale crystal with a cubic shape. Raw materials are an important factor in determining the synthesis of nanocubes. In this study, we investigated various niobium compounds that serve as raw materials, each inducing different effects during nanocube synthesis. Perovskite sodium niobate (NaNbO3) nanocubes were synthesized using a two-step process. The first step in this process, synthesis of the raw materials, was followed by solvothermal synthesis of NaNbO3 nanocubes. The raw material for the first step was obtained by applying heat treatment to a precursor following Nb hydrolysis. The heat treatment was performed at temperatures of 300-1000°C. Nb2O5 was obtained after heat treatment of its precursor, during which its crystalline system morphed into hexagonal, orthorhombic, and monoclinic systems with respective increases in temperature. For the second step, we obtained various NaNbO3 morphologies via the solvothermal method using water, methanol, or ethanol as a reaction medium. NaNbO3 nanocubes were formed by applying the solvothermal method to the synthesized precursor during heat treatment at 800°C. Solvothermal synthesis was performed with methanol as the reaction medium at 200°C, which resulted in the formation of NaNbO3 nanocubes. [ABSTRACT FROM AUTHOR]

A novel Ag–TiO2-sepiolite antibacterial nanocomposite was prepared by a one-pot solvothermal method in acetic acid–water solution. The ternary nanostructures consist of Ag-decorated TiO2 nanoparticles (NPs) supported with sepiolite nanofibers. Sepiolite served as a template for reducing the agglomeration of TiO2 NPs and improving the interface reactions between the nanocomposite and bacteria cells. Ag NPs were introduced to enhance the absorption of visible light, and suppress the recombination of electron–hole pair. The synergistic effects of TiO2, Ag NPs and sepiolite nanofibers led to the superior antibacterial activity of the Ag–TiO2-sepiolite nanocomposite against Gram-negative Escherichia coli and Gram-positive Staphylococcus aureus. [ABSTRACT FROM AUTHOR]