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Hydrogen is an important energy carrier without carbon emissions. To achieve a carbon‐neutral world, the demand for hydrogen is very significant. In the process of producing green hydrogen, water splitting using electrocatalysts is a desirable process among many methods. The ideal electrocatalyst for hydrogen evolution is the platinum group of metals; however, the limitations of high cost and low abundance hinder large‐scale hydrogen production. Hence, researchers are trying to develop materials from more abundant and less expensive. Hence, in this review, we focus on the fundamental principles of hydrogen evolution reaction (HER) and various synthesis methods and strategies. From the material perspective, we focus on nickel sulfide‐based nanomaterials of different phases during the last four years of development. We compared the electrocatalyst parameters concerning the synthesis methods and strategies chosen. Finally, we have also discussed future challenges. Ultimately, by synthesizing the collective knowledge amassed in the field of HER research, this review endeavors to offer a comprehensive resource for researchers, engineers, and policymakers striving to advance hydrogen‐based energy technologies. In doing so, we aspire to foster continued innovation and collaboration toward realizing a sustainable energy future powered by hydrogen. [ABSTRACT FROM AUTHOR]

Construction of prosperous morphology and incorporation of multiple metals with synergistic effect can effectively enhance the electrochemical performance of electrode materials. Herein, transition metal (Ni, Co, Mo) sulfides (NCM‐DI, NCM‐DI‐NTA, NCM‐EG, NCM‐EG‐NTA, NCM‐Mix‐NTA) were synthesized, and the morphology was adjusted by incorporating metal ligand and altering the solvent atmosphere. The addition of ligand nitrilotriacetic acid (NTA) endowed the formation of cross‐linked network (NCM‐DI‐NTA, NCM‐EG‐NTA, NCM‐Mix‐NTA), and the as‐prepared materials generated in mixed solvent (NCM‐Mix‐NTA) displayed smaller size. Materials with NTA added (NCM‐DI‐NTA, NCM‐EG‐NTA, NCM‐Mix‐NTA) displayed higher specific capacity (754, 943 and 1206 F g−1, respectively), which is much higher than NCM‐EG (909 F g−1) and NCM‐DI (331 F g−1). After doped with rGO, the materials (NCM‐Mix‐NTA‐rGO) exhibited a specific capacity of 1984 F g−1 at 1 A g−1. When assembled into asymmetric supercapacitors, it delivered the energy density of 61.6 Wh kg−1 at a power density of 901.4 W kg−1, and maintained the 86.5 % of their initial capacity even after 5000 cycles. [ABSTRACT FROM AUTHOR]

This study demonstrates a facile solvothermal approach to synthesizing green fluorescent carbon dots (G‐CDs) using baby pumpkin as a natural precursor. The G‐CDs exhibit strong fluorescence emission at 547 nm under excitation at 467 nm, and the highest quantum yield reaching 17.5 % in acetone, making them suitable for a range of applications including sensing, bioimaging, catalysis, and drug delivery. The G‐CDs demonstrate excellent stability under various conditions, such as prolonged light exposure, high salt concentration, extended periods, and elevated temperatures. Furthermore, the G‐CDs show a good linear relationship with Cd2+ within the concentration range of 0 to 16.5 μmol/L, with a linear correlation coefficient of 0.9920. The detection limit (LOD) was calculated to be 0.68 μmol/L. The recovery rate ranges between 85.66% to 97.43%, indicating their potential for use in environmental metal ion detection. This study provides a convenient and economical method for the synthesis of G‐CDs using baby pumpkin as a precursor, offering a sustainable alternative for various applications in sensing, imaging, catalysis, and drug delivery. [ABSTRACT FROM AUTHOR]

Supercapacitors have been widely studied as a typical representative of new energy storage systems. As a type of novel crystalline porous material, covalent triazine frameworks (CTFs) have attracted enormous attention owing to their high nitrogen content and unique triazine ring structure, which give them high chemical and thermal stability. In this paper, 2,4,6‐tris(4‐aldophenyl)‐1,3,5‐triazine (TFPT) and 2,4,6‐tris(4‐aminophenyl)‐1,3,5‐triazine (TAPT) were used to synthesize TPT‐CTFs by Schiff base reaction. TPT‐CTFs exhibit regular nanosheets structure and high crystallinity. The specific capacitance of TPT‐CTFs is 110 F/g at current density of 0.1 A/g. After 10,000 cycles of charge and discharge, the capacitance retention rate is high as 105%, due to the high crystallinity support and expandable channels of TPT‐CTFs. In addition, the simple and convenient one‐pot hydrothermal synthesis used in this paper, avoids harsh conditions of common ampoule methods for synthesis of CTFs materials. [ABSTRACT FROM AUTHOR]

Black phosphorus (BP) nanosheets have been widely used in the field of electronic devices for their exceptional qualities, but the preparation and optical properties of black phosphorus nanosheets need to be further explored. Herein, high fluorescence intensity black phosphorus nanosheets are prepared by a simple and economical solvothermal method using red phosphorus (RP) and ethylenediamine as raw materials. The physical structure and morphology of black phosphorus nanosheets crystals are characterized by X‐ray diffractometer (XRD), Raman spectrometer, transmission electron microscope (TEM), and atomic force microscope (AFM), and the effect of the concentration of raw material to solvent ratio on the structure and optical properties of the prepared black phosphorus nanosheets are also investigated. Black phosphorus nanosheets containing mostly monolayer structures with transverse dimensions of about 200 nm are obtained using the solvothermal method. When the preparation parameter is RP/EDA = 30 g L−1, the room‐temperature photoluminescence center of the black phosphorus nanosheets is 470 nm with superior luminescence performance. [ABSTRACT FROM AUTHOR]

Battery‐type supercapacitors have drawn significant attention due to their high charge storage ability resulted from the combined surface and intercalation redox phenomenon. In this regard, nickel chalcogenides are expected to deliver high specific capacity accompanied by their dominant battery‐type supercapacitor features. Herein, we have developed a facile one step solvothermal route to prepare pure phase Ni3Se4 nanostructures and attempted to understand the synthetic factors such as solvent and Ni/Se ratio on the formation of Ni3Se4 phase. The obtained Ni3Se4 nanostructures were subjected to the supercapacitor performance evaluation by loading them onto carbon paper and found that the electrode materials are able to store the charge through dominant intercalation redox process (battery‐type storage mechanism). Among them, Ni3Se4 (NS‐15E(1)) synthesized in water/ethanol (2 : 3) mixture with Ni/Se (1 : 1) ratio has displayed a high specific capacity of 376 C g−1 (104 mA hg−1) at a current density of 1 A g−1 in 2 m KOH. The superior charge storage of NS‐15E(1) could be attributed to the improved redox process facilitated by the easier diffusion of electrolyte ions into the bulk of the material. Furthermore, a hybrid device fabricated by using Activated charcoal (AC) and NS‐15E(1) as negative and positive electrodes, respectively has showed an extended voltage window of 1.6 V and achieved a high energy density ∼20 Wh Kg−1 at a power density of 329 W kg−1. [ABSTRACT FROM AUTHOR]

Heterogeneous photo‐Fenton oxidation is a promising solution to solve the problem of environmental pollution. Due to the low efficiency of the Fe2O3 photo‐Fenton catalyst, we loaded Fe2O3 on the catalyst carrier of attapulgite (ATP) to obtain more active sites. Oxygen vacancies were introduced on the surface of the catalyst to improve the separation efficiency of photogenerated charges. The oxygen‐vacancy‐rich e‐Fe2O3/SiO2/ATP Fenton‐like photocatalyst was successfully synthesized by simple strategies. The oxygen vacancies were successfully introduced to the surface of the e‐Fe2O3/SiO2/ATP catalyst by a solvothermal method, and verified by XPS, Raman and EPR spectra. The e‐Fe2O3/SiO2/ATP Fenton‐like photocatalyst shows excellent photocatalytic degradation activity of MB and RhB. 96 % of RhB was degraded by e‐Fe2O3/SiO2/ATP with light in 60 min, and 95 % of MB was degraded by e‐Fe2O3/SiO2/ATP with light in 60 min. Therefore introducing surface oxygen vacancies is an effective strategy to future improve the catalytic activity of photo‐Fenton like catalysts. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) are emerging as promising candidates for hydrogen storage material because of their porosity and adjustable hydrocarbon structures coordinated with the metal element. Present work explore the synthesis of M2(m‐dobdc) (M = Fe and Mn; m‐dobdc4− = 4,6‐dioxido‐1,3‐benzenedicarboxylate) metal‐organic frameworks via solvothermal method for the purpose of hydrogen storage application. The X‐ray diffraction, transmission electron microscope, scanning electron microscope, energy dispersive X‐ray analysis, and nuclear magnetic resonance spectroscopic studies have been done to ensure the synthesized material is M2(m‐dobdc) (M = Fe and Mn) MOFs. The Brunauer‐Emmett‐Teller (BET) analysis reveals the average pore size of 36.271 nm for Mn2(m‐dobdc) MOF whereas the average pore size for fe2(m‐dobdc) MOF was found to be 2.1992 nm. The as‐prepared MOF samples are in the mesoporous range based on pore size distribution (internal pore diameter greater than 2 nm) with spherical pore geometry. Hydrogen storage studies shows that Fe2(m‐dobdc) has a hydrogen storage capacity of 0.18 wt% at ambient temperature (30°C) under 100 atm H2 pressure, whereas the hydrogen storage capacity for Mn2(m‐dobdc) is 1.38 wt% under identical conditions of temperature and pressure. The hydrogen storage capacity at liquid nitrogen temperature (−196°C) under 100 atm H2 pressure for Fe2(m‐dobdc) and Mn2(m‐dobdc) is 4.31 and 8.21 wt%, respectively. [ABSTRACT FROM AUTHOR]

Here we propose a simple one‐pot solvothermal method to synthesize well‐dispersed CuO catalysts over carbon black surface for application in CO2 electrolysis. Although simple, the route produced catalysts with good performance even in lower CuO contents, increasing the efficiency of the catalytic layer. Films prepared by straightforward dropping on fluorine tin oxide (FTO) substrates were stable (up to 30 hours), showing good activity for CO2 reduction reaction (CO2RR) and controlling the competitive H2 evolution to preferentially form CO2 reduction products (CO, formic acid, ethanol, and acetic acid). The results showed values of almost 50 % of faradaic efficiency for products of CO2 reduction, comparable with other more elaborated catalysts reported in the literature, even utilizing cheap support, easy synthesis, and lower potentials. [ABSTRACT FROM AUTHOR]

This work reported the synthesis of Ce‐MOF and Nd‐MOF adsorption materials using the solvothermal method with the rare earth metals Ce3+ and Nd3+ as the particle center and discussed the adsorption effect of the two synthesized nanomaterials on the VOCs released by dry wood. The porous morphology of the material increases the benzene gas contact area. The maximum adsorption capacity of benzene, according to the Langmuir model, is 128.98 mg/g and 132.22 mg/g, respectively. The method has a large adsorption capacity, good adsorption effect, non‐toxic and harmless, low recycling cost, recyclable multiple times, simple operation, stable structure, no secondary environmental pollution, etc., and has good application prospects in the wood drying industry. [ABSTRACT FROM AUTHOR]

Ammonia is an indispensable chemical, of which the industrial production is still dominated by Haber‐Bosch process operated at harsh conditions. The ecofriendly electrocatalytic N2 reduction reaction (NRR) emerges as an alternative, however, such technique currently suffers from tough dynamics on account of difficulties in the adsorption or protonation of N2 on catalysts. To eliminate the obstacle, a simple and valid strategy of ferrous iron replacing copper is proposed to regulate the electronic structure of layered double hydroxide (LDH) for boosting the NRR activity. Thanks to the ferrous iron, the Fe(II)Cu(II)Fe(III)‐LDH catalyst attains a NH3 yield rate of 33.1 ± 2.5 µg h−1 mgcat.−1 and a desirable Faradaic efficiency (FE) of 21.7 ± 1.8% in a neutral electrolyte of 0.1 m Na2SO4, outclassing the Cu(II)Fe(III)‐LDH catalyst without Fe(II). The introduction of ferrous iron can adjust the d‐band center position to improve the N2 adsorption and can reduce the energy barrier of the potential determining step (PDS) to facilitate the NRR process. This work provides a new insight on engineering efficient electrocatalysts for nitrogen fixation under ambient conditions. [ABSTRACT FROM AUTHOR]

The time‐consuming and laborious heat treatment is indispensable for preparing seed layer in solvothermal synthesis of WO3 film. Herein, WO3 film is prepared composed of single crystal WO3 nanowires on indium tin oxide (ITO) glass assisted with simple and energy‐saving electrodeposited seed layer for the first time. The catalyst Pt is sputtered on it for 30 s after WO3 film is synthesized to form the hydrogen gasochromic film. The film structure is redesigned to improve its hydrogen gasochromic properties further. Before WO3 film is solvothermally synthesized, Pt is sputtered on seed layer for 15 s, then it is sputtered for 15 s again after WO3 film is prepared. The Pt sputtered on seed layer greatly changes the morphology of nanowires, making them sparse, slender, and cross‐linked like a bird's nest. Moderate 37% HCl is added during the solvothermal process to promote the growth of WO3 nanowires. The variation of transmittance (wavelength: 1000 nm), coloring rate (4% H2/Ar) and bleaching rate (air) of WO3 hydrogen gasochromic film with new structure at room temperature are 69.1%, 3.1%/s (increases 19.6%) and 0.85%/s (increases 193%), respectively. This study offers a new strategy for seed layer technology of WO3 film and structural design of WO3 hydrogen gasochromic film. [ABSTRACT FROM AUTHOR]

Transition metal phosphides are emerging as potential anode materials for lithium‐ion batteries (LIBs) due to their high theoretical capacity and good thermal stability, but the severe volume changes during the charge/discharge process and low electrical conductivity have hampered their practical application. Herein, the facile synthesis of carbon‐coated CoP nanoparticles (CoP@C) with uniform spherical morphology is demonstrated through the solvothermal method followed by annealing and phosphating treatments, in which an interesting precursor, the Co–gluconate complex, is prepared as the Co/C sources. When used as the LIB anode, the CoP@C electrode displays excellent cycling stability with a reversible capacity of 483.4 mA h g−1 upon 1000 cycles at 0.5 A g−1. The superior lithium storage performance is attributed to the unique composite structure of CoP@C with the nanosized CoP particles wrapped into the carbon matrices, which can enhance the electrical conductivity, provide sufficient reaction sites, shorten the Li+ transport path, and buffer the volume changes of the electrode upon lithiation/delithiation. More importantly, the strategy of generating gluconate–metal complex as the metal‐ and carbon‐containing precursor can be widely applied in the synthesis of various functional materials for energy‐related applications. [ABSTRACT FROM AUTHOR]

Cu‐MOF/graphene composite were obtained by solvothermal and electrochemical methods. The interaction and formation of Cu‐MOF/graphene (GE) composite was systematically studied with the support of various characterizations including X‐ray diffraction (XRD), field emission scanning electron microscopy (FE‐SEM) and cyclic voltammogram (CV). The Cu‐MOF/graphene composite coated glassy carbon (GC) electrode exhibited good catalytic performance towards the electro‐oxidation of caffeine in neutral condition. The modified electrode displayed good linear range (5 μM to 450 μM), sensitivity (0.710 μA μM−1 cm−2), detection limit (1.38 μM), selectivity, high stability and reproducibility. Finally, the fabricated electrode extended into successful detection of caffeine in tea and coffee samples with good recoveries. [ABSTRACT FROM AUTHOR]

UiO‐66 nanoparticles (NPs) were prepared by the solvothermal method using deep eutectic solvents (DESs) and compared to those prepared using the traditional solvent, dimethylformamide. A mixture of choline chloride:glycerol with a molar ratio of 1:2 was used as a green solvent to prepare the NPs. SEM, a Fourier transform infrared spectrometer, zeta potential, N2 adsorption/desorption, and surface area characterisations were used to characterise the NPs. Results showed that the NPs formed in the DES had a smaller size but the lower surface area and functionalised with new chemical groups due to the DES effect. Also, the modified metal–organic frameworks surface area increased by increasing the incubation time but decreased by increasing the temperature. [ABSTRACT FROM AUTHOR]

Lead‐free single crystal perovskite materials exhibit impressive characteristics, such as high carrier mobility, low trap density, and long diffusion length. Herein, the high‐performance blue light photodetectors are reported based on lead‐free all‐inorganic Cs3Sb2Br9 perovskite single crystals. These millimeter‐sized Cs3Sb2Br9 single crystals have small thermal activation energy of 56.8 meV estimated by temperature‐dependent photoluminescence study. There is no obvious structural phase transition of the as‐obtained Cs3Sb2Br9 single crystals since no Raman peak shift is observed with temperature increasing from 80 to 300 K. The as‐constructed high quality Cs3Sb2Br9 single crystals photodetectors have an excellent performance of a responsivity of 2.29 A W−1, a sharp detectivity of 3.77 × 1012 Jones, and an external quantum efficiency (EQE) peak of 1.8 × 103%. Moreover, the photodetectors exhibit a fast response time (<0.2 ms) and the full width at half maximum (FWHM) of the sharp EQE peak is as narrow as 15 nm. This work provides a promising strategy in the design of lead‐free, stable, and high‐performance perovskites for photodetector devices. [ABSTRACT FROM AUTHOR]

A magnetic covalent organic framework material was synthesized with a core‐shell structure using a simple solvothermal method. It was prepared with Fe3O4 as the magnetic core, covalent organic framework as the shell, which synthesized from 1,3,5‐triformylphloroglucinol and p‐phenylenediamine by Schiff base reaction. Transmission electron microscopy, Fourier transform infrared spectroscopy, powder X‐ray diffraction, vibrating sample magnetometry, and nitrogen adsorption‐desorption were used to characterize magnetic adsorbent. It has showed a large specific surface area (505.6 m2/g), which can provide many adsorption sites. Moreover, the saturation magnetization value was 48.4 emu/g enough to be separated by external magnet. Six kinds of fluoroquinolones (enoxacin, fleroxacin, ofloxacin, norfloxacin, pefloxacin, and lomefloxacin) were extracted by magnetic solid phase extraction with the magnetic adsorbent. High‐performance liquid chromatography detects the entire adsorption and desorption process to further evaluate the optimal extraction and desorption conditions. Under the optimal chromatographic conditions, this method showed a low detection limit (0.05 to 0.20 μg/L), good linearity in the range of 0.5 to 200 μg/L, and the enrichment factor reaches 115.5‐127.3. The spiked recovery of the fluoroquinolones in milk sample ranged from 90.4 to 101.2%. [ABSTRACT FROM AUTHOR]

The incorporation of additional metal to form homo/heterojunction nanomaterials may enhance electrical conductivity and electrocatalytic performance. In this work, a novel Ni−Fe‐Se compound made through a facile solvothermal method with the presence of D‐(+)‐glucose (labeled as Ni0.5Fe0.5Se2/C) exhibited outstanding catalytic activity toward water oxidation. During oxygen evolution reaction (OER) process in alkaline condition, Ni0.5Fe0.5Se2/C catalyst shows an overpotential of 254 mV at 10 mA cm−2, 77 mV lower than that of the commercial RuO2, and an excellent stability. [ABSTRACT FROM AUTHOR]

Hexagonal pyramidal β‐NaYF4:Eu3+ are synthesized with a facile solvothermal method using the mixture of ethylene glycol and deionized water (DIW) as the reaction solvents. The solvent ratio has a strong effect on the morphology, growth, and photoluminescence (PL) properties of β‐NaYF4:Eu3+. Both the particle size and the aspect ratio of length/diameter of the β‐NaYF4:Eu3+ increase with the proportion of DIW in the reaction solvents, and their crystallinity is also enhanced. The growth behavior of the β‐NaYF4:Eu3+ has been analyzed and explained based on the intrinsic crystal structures, the surface free energy, and the interactions between the reacting ions. The PL of the β‐NaYF4:Eu3+ greatly increases with the proportion of DIW in the reaction solvents, and this is attributed to their enhanced crystallinity with lower density of nonradiative defects. Herein, a useful basis for preparation of luminescent materials with adjustable morphology and strong PL is provided. [ABSTRACT FROM AUTHOR]

Recently, nanozymes have attracted extensive attention because of their advantages of combining nanomaterials with enzymes. Herein, hexagonal boron nitride (h‐BN) and nitride‐doped molybdenum disulfide (N−MoS2) nano‐composites (h‐BN/N−MoS2) were synthesized by facile and cost‐effective liquid exfoliation with a solvothermal method in nontoxic ethanol solution. The results show that h‐BN, as a co‐catalyst, can not only dope into the lattice of MoS2 but also form a heterogeneous structure with MoS2NSs. It expanded the layer spacing and specific surface area of MoS2NSs, which was beneficial to the contact between the catalyst and the substrate, and resulted in a synergistic enhancement of the catalytic activity of hydrogen peroxide (H2O2) with MoS2. A colorimetric determination platform of h‐BN/N−MoS2‐TMB‐H2O2 was constructed. It exhibited a wide linear range of 1–1000 μM with a low limit of detection (LOD) of 0.4 μM under optimal conditions, high sensitivity and stability, as well as good reliability (99.4–110.0%) in practice, making the measurement system more widely applicable.1. Introduction [ABSTRACT FROM AUTHOR]

Recently, nanozymes have attracted extensive attention because of their advantages of combining nanomaterials with enzymes. Herein, hexagonal boron nitride (h‐BN) and nitride‐doped molybdenum disulfide (N−MoS2) nano‐composites (h‐BN/N−MoS2) were synthesized by facile and cost‐effective liquid exfoliation with a solvothermal method in nontoxic ethanol solution. The results show that h‐BN, as a co‐catalyst, can not only dope into the lattice of MoS2 but also form a heterogeneous structure with MoS2NSs. It expanded the layer spacing and specific surface area of MoS2NSs, which was beneficial to the contact between the catalyst and the substrate, and resulted in a synergistic enhancement of the catalytic activity of hydrogen peroxide (H2O2) with MoS2. A colorimetric determination platform of h‐BN/N−MoS2‐TMB‐H2O2 was constructed. It exhibited a wide linear range of 1–1000 μM with a low limit of detection (LOD) of 0.4 μM under optimal conditions, high sensitivity and stability, as well as good reliability (99.4–110.0%) in practice, making the measurement system more widely applicable.1. Introduction [ABSTRACT FROM AUTHOR]

V2O3 is considered to be a potential anode material due to its large specific capacity and rich resources. Herein, flock‐like V2O3 coated with carbon is prepared through a facile and simple solvothermal method followed by annealing at a relatively low temperature. The structure of V2O3/C is composed of porous strips. Due to the unique morphology and structure, the V2O3/C anode material shows excellent electrochemical performance. It delivers a specific discharge capacity of 696 mAh g−1 after 100 cycles, which is 95% of the specific discharge capacity (732 mAh g−1) after the sixth cycle. The V2O3/C anode material annealed at 360 °C (V2O3/C‐360) delivers 601 mAh g−1 at a current density of 300 mA g−1 after 500 cycles. It implies superior cyclic stability of V2O3/C‐360. In addition, the anode also shows excellent rate capability. Specific capacities of approximately 600, 420, and 300 mAh g−1 are obtained at the current densities of 0.3, 2, and 5 A g−1, respectively. The large current contribution of the capacitive reveals favorable superior lithium storage kinetics. This anode material presents great application potential in high‐performance lithium‐ion batteries. [ABSTRACT FROM AUTHOR]

A comparative study on the role of urea in controlling the morphology of calcium‐bismuth (Ca5Bi3) bimetallic nanoparticles is carried out. Calcium‐bismuth bimetallic nanoparticles are synthesized in the presence and absence of urea using the solvothermal method. The morphology of the synthesized products is analyzed by scanning electron microscopy. The composition of the product is analyzed by energy‐dispersive X‐ray spectroscopic and X‐ray diffraction (XRD) analyses. Reitveld refinements are performed on the XRD data, and lattice parameters are optimized. Reitveld‐refined parameters are used to construct the structural model of the calcium‐bismuth product. The formation mechanism of needle like particles from an orthorhombic unit cell is also proposed. The degradation of Congo red dye is catalyzed by synthesized Ca5Bi3 bimetallic nanoneedles in an aqueous medium. The effect of catalyst dose on the apparent rate constant (kapp) of degradation is studied and compared with literature. Ca5Bi3 bimetallic nanoneedles are also used as an additive in commercial diesel obtained from Pakistan State Oil, Limited. The effect of an additive dose on the calorific value of diesel is studied. How the Ca5Bi3 additive influenced other fuel quality parameters such as flash point, fire point, pour point, cloud point, kinematic viscosity, and specific gravity is also studied. [ABSTRACT FROM AUTHOR]

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]

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]

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]

Low‐cost and high yield silver nanorings with the uniform ring diameter of 15±5 μm and thickness of 120±20 nm were synthesized via a simple solvothermal method. Based on our knowledge, this is the first time that a solvothermal method is used to prepare silver nanorings. Herein, by using ammonium salts as additive salts in the presence of pressure (150 kPa) inside the reactor, the reproducibility and yield of nanorings increased. The prepared silver nanorings easily dispersed in ethanol and have been coated by spray method on PET substrate to make flexible transparent conductive films (TCF). The film based on nanorings was shown better opto‐electrical properties (higher transparency with lower haze) in comparison with nanowires with higher aspect ratio and lower thickness, at the same sheet resistance (Rs). These results introduce silver nanorings as outstanding candidates for optoelectronics applications. Put a ring on it: Silver nanorings with high purity in high yield with uniform diameter and thickness were synthesized through facile solvothermal method. The conductive ink based on silver nanorings was successfully prepared and coated on PET substrate. The opto‐electrical properties of TCF with nanorings were improved in comparison with TCF with nanowires at the same sheet resistance (see figure). [ABSTRACT FROM AUTHOR]

Here, we report the synthesis and characterization of palladium nanoparticles immobilized on (Pd@DASs) triazine containing covalent organic polymer prepared through solvothermal method to the formation of Schiff base polymer condensation reaction between 1,4‐diaminobenzene and 4,4′,4′′‐(1,3,5‐triazine‐2,4,6‐triyl)tribenzaldehyde, respectively. The synthesized Pd@DASs was thoroughly characterized by various techniques including FT‐IR, UV‐DRS, EDAX, powder XRD, scanning electron microscopy (SEM) and X‐ray photoelectron spectroscopy. Furthermore, the prepared Pd@DASs potential catalytic performance was evaluated for Sonogashira cross‐coupling of various aryl halides with phenylacetylene, K2CO3 as a base in water/DMF (2:1) solvent for about 3 h and the same catalyst was used for reduction of nitroarenes using hydrazine hydrate (Hydrogen source) in methanol/water (1:2) mixture of solvent for about 1.30 h under mild reaction conditions. Neither copper and nor ligand and additives are required in the reaction medium, which exhibits high catalytic activity and excellent to good yield (upto 96% and 99%), the catalyst can be separated easily and recycle for several times. Palladium nanoparticles immobilized on (Pd@DASs) triazine containing covalent organic frames prepared and evaluated the catalytic condition for Sonogashira cross‐coupling and reduction of nitroarenes under mild reaction condition with very good yield upto 96% and 99% respectively. [ABSTRACT FROM AUTHOR]

The incorporation of a foreign metal into a material may adjust the surface electronic structure and promote charge transfer, which then ultimately improves electrical conductivity and electrocatalytic performance because of the possible charge delocalization between the metal cations. As a result, for the first time, ternary nickel iron sulfide nanospheres have been successfully fabricated through a two‐step solvothermal approach with the help of glucose (Ni0.5Fe0.5S2/C). Subsequently, the electrochemical performance and electrocatalytic activity of Ni0.5Fe0.5S2/C were evaluated by electrochemical impedance spectroscopy, Tafel polarization and cyclic voltammetry, indicating high electrical conductivity and great electrocatalytic activity. Ni0.5Fe0.5S2/C was employed as a counter electrode for dye‐sensitized solar cells, and exhibited higher power conversion efficiency (6.79 %) than the device with Pt CE (6.31 %) under full sunlight illumination (100 mW cm−2, AM 1.5G). Caught the sun: For the first time, ternary nickel iron sulfide nanospheres have been successfully fabricated through a two‐step solvothermal approach with the help of glucose (See Figure). Subsequently, the electrochemical performance and electrocatalytic activity of Ni0.5Fe0.5S2/C were evaluated for application in dye‐sensitized solar cells [ABSTRACT FROM AUTHOR]

Transition metal hydroxides have attracted considerable attention as promising electrode materials in electrochemical energy storage. In this work, we first used a facile and green approach to synthesize Ni4Yb(OH)10NO3 ⋅ 3H2O nanosheets, which are thin‐layer hexagonal structures. Additionally, this method can be developed to synthesize other lanthanide‐doped Ni(OH)2 materials. When used as electrode materials, these nanosheets exhibited excellent electrochemical energy storage performance and good cycling stability. For example, the Ni4Yb(OH)10NO3 ⋅ 3H2O nanosheet electrode showed a specific capacitance of 1482.1 F g−1 at 1 A g−1, while maintaining great cycling stability (a capacity retention of 71.8 % after 2000 cycles at a current density of 1 A g−1). Sheet music: Ni4Yb(OH)10NO3 ⋅ 3H2O nanosheets are synthesized by using a facile and green method, and are subsequently demonstrated to have excellent electrochemical energy storage performance. [ABSTRACT FROM AUTHOR]

Porous Co3O4 nanocatalysts with tunable size were fabricated by solvothermal method using different solvent, such as ethanol, ethylene glycol and water, respectively. After that, the Pd was successfully loaded on the Co3O4 precursor by impregnation method to obtain Pd/Co3O4 catalysts, which were used in toluene total oxidation. The catalyst prepared with ethanol as solvent (Pd/Co3O4‐E) exhibited excellent catalytic performance and the total conversion temperature (T100) was 200 °C at a weight hourly space velocity of 21000 h−1. The influence factors for the performance of the catalysts were characterized by a series of techniques. The SEM, TEM and XRD results of Pd/Co3O4 catalysts displayed the different structure by using different solvent and the Pd/Co3O4‐E exhibited the largest size about 13.6 nm. The BET surface area, surface adsorbed oxygen of the Pd/Co3O4 leaded to the superior activity for toluene total oxidation. The catalytic performance of Pd/Co3O4 catalysts was also associated with the effect of BET surface area of Co3O4 support on Pd dispersion, surface active oxygen and the interaction between Pd nanoparticles and Co3O4. Different nanoparticles sizes of Co3O4 were fabricated via the solvothermal method, and Pd/Co3O4 catalyst was successfully fabricated by impregnation methods for the removal of toluene. The Pd nanoparticles were uniformly dispersed on the surface of the Co3O4 sample. The Pd/Co3O4 catalyst prepared with ethanol as solvent exhibits an unexpected, surprisingly high catalytic activity. [ABSTRACT FROM AUTHOR]

Germanophosphates, as a young class of metal phosphates, have been less reported but might possess more diverse structural types and potential applications. Here, two one‐dimensional (1D) alkali‐metal germanophosphates (GePOs), namely, hydrogen hexakis(μ‐hydrogen phosphato)digermaniumtrirubidium, HRb3Ge2(HPO4)6 (1), and caesium bis(μ‐hydrogen phosphato)(μ‐hydroxido)germanium, CsGe(HPO4)2(OH) (2), have been prepared by the solvothermal method. Compound 1 shows 1D [Ge(HPO4)6]∞ chains along the c axis formed by GeO6 octahedra and PO4 tetrahedra, with Rb+ cations dissociated between the chains. Compound 2 also exhibits 1D [Ge(HPO4)4(OH)2]∞ chains constructed from adjacent Ge(HPO4)4(OH)2 octahedra, with Cs+ cations dissociated between the chains. XRD, TGA, IR and UV–Vis–NIR absorption spectra are presented and discussed for both compounds. [ABSTRACT FROM AUTHOR]

The development of antibiotic resistance among hospital pathogens has provided a great need for new antimicrobial agents. Zinc oxide nanoparticles (ZnO NPs) in combination with various antibiotics can act as a reducing agent for antibiotic resistance. The aim of this study was to investigate the influence and the mechanism of ZnO NPs on the antimicrobial activity of ciprofloxacin (CP) and ceftazidime (CAZ) against Enterococcus faecalis (E. faecalis) and Acinetobacter baumannii (A. baumannii) bacteria in acidic conditions (pH 5.5). ZnO NPs were synthesised using the solvothermal method and characterised. The MIC90 value of ZnO NPs against A. baumannii was 0.25 mg ml−1 and its highest growth‐inhibitory activity was observed at 0.125 mg ml−1 for E. faecalis. The Fourier transform infrared spectroscopy spectra of ZnO NPs treated with antibiotics showed the interaction between ZnO NPs and each of the two antibiotics. ZnO NPs at a sub‐inhibitory concentration had no effect on the antibacterial activity of CP and CAZ against E. faecalis and CP against A. baumannii. The action mechanism of ZnO NPs for enhancing the antibacterial efficacy of CAZ against A. baumannii was evaluated. ZnO NPs caused to increase in the antibacterial activity of CAZ against A. baumannii, possibly through the release of Zn2+ and increasing of membrane permeability. [ABSTRACT FROM AUTHOR]

The magnesium ferrite nanorods/graphene (MgFe2O4 NR/G) composites were prepared by a facile one‐step surfactant‐assisted solvothermal method. The structure and morphology of as‐prepared composite materials were characterized by electron microscopy, energy dispersive spectrometry, Raman spectrometry, X‐ray diffraction, FT‐IR and X‐ray photoelectron spectroscopy. The homogeneous MgFe2O4 nanorods with a typical diameter of about 100 nm were well distributed on graphene. The electromagnetic parameters were measured using a vector network analyzer. A minimum reflection loss (RL) of −40.3 dB was observed at 14.9 GHz with a thickness of 3 mm, and the effective absorption frequency (RL  <   − 10 dB) ranged from 12.0 to 18.0 GHz, indicating the remarkable microwave absorption performance of the MgFe2O4 NR/G composites. The absorbing property of as‐obtained composites was better than that of the pure MgFe2O4 nanorods. The synergistic effect of MgFe2O4 and graphene was responsible for the enhanced absorbing performance. [ABSTRACT FROM AUTHOR]

Abstract: CuInS2 powders were prepared by solvothermal method. The effects of experimental conditions on crystal structure, composition phase and morphology were investigated systematically. The phases of product samples were analyzed by X‐ray diffraction (XRD) on the Bruker D8 Advance XRD system with Nifiltered Cu‐Kα (λ = 1.5059 Å). The morphology of the product powders were observed using scanning electron microscope (SEM) with a model of JSM‐6380LA made by Japan Electronics Co., Ltd. The elemental compositions of the product powders were analyzed by energy dispersive spectroscopy (EDS). The results show that, different solvents have important effects on the crystal structures of CuInS2 powders. With CuC12·2H2O, InCl3 and SC(NH2)2 as raw materials, the wurtzite CuInS2 obtained with the mixed solvent of ethanol and hydrazine hydrate has better crystallinity than that obtained by the mixed solvent of ethylene glycol and hydrazine hydrate. The product powder obtained with ethanol without hydrazine hydrate has major phase chalcopyrite CuInS2. The wurtzite CuInS2 powder consists of aggregated particles with diameters of 0.1 ∼ 0.5 μm. The sample with chalcopyrite has relatively more large particles with diameters of 3 ∼ 5 μm which consist of smaller flakes. The optimum conditions for preparing wurtzite CuInS2 powder are at 160 °C for 20 h using CuC12·2H2O, InCl3 and SC(NH2)2 as raw materials and the mixed solution of ethanol and hydrazine hydrate as solvent. With the increase of reaction temperature, the XRD peaks of chalcopyrite CuInS2 are more obvious, but the new impurity phase Cu2S appears at 220 °C. With holding time prolonging, it is helpful to eliminate the XRD peaks of impurity and promote chalcopyrite CuInS2 formation. The optimum conditions for chalcopyrite CuInS2 are reacting at 220 °C for 30 h with ethanol without hydrazine hydrate as solvent and CuC12·2H2O, InCl3 and SC(NH2)2 as raw materials. [ABSTRACT FROM AUTHOR]

Present work reports for the first time on successful synthesis of polyethylene glycol (PEG) coupled ZnO-chemically converted graphene (CCG) nanocomposites (ZGP) as well as pristine nano ZnO (ZO), ZnO-CCG (ZG) and ZnO-PEG (ZP) by adopting facile solvothermal method using zinc acetate dihydrate, graphene oxide and PEG as precursor materials. X-ray diffraction measurement of samples showed nanocrystalline hexagonal ZnO. Agglomeration of ZnO nanoparticles formed microspheres in ZG, and the agglomeration was found to be decreased in ZGP as revealed from field emission scanning and transmission electron microscopes. Raman and FTIR spectral studies evidenced the presence of chemically interacted CCG and polyethylene glycol in the nanocomposites. Content of the organics in ZGP was determined by thermogravimetric analysis. A mechanism was proposed on the formation of ZGP nanocomposite. From the measurement of in vitro cytotoxicity, quantitative cell viability (CV) of human ovarian cancer cell line, OAW42, was obtained from control to a maximum of 200 µg/ml of sample concentrations. An excellent CV of the cancer cells was observed (nearly ~80% of viable cells at 50 µg/ml dose with respect to the control) for ZGP compared to ZO, ZG and ZP samples. The effective role of CCG and PEG in ZGP nanocomposite for enhancing the cell viability was explained. This simple strategy could be beneficial for synthesis of other metal oxide towards biomedical applications. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Containing two environmentally friendly elements, tin monosulfide (SnS) is considered to be a possible candidate for sustainable thermoelectrics in the medium temperature range. Nanostructured SnS was synthesized via mechanical alloying and a solvothermal method. Two different ways for compacting of the nanopowders were applied, cold pressing and hot pressing, yielding similar results. A maximum ZT value of 0.075 at 773 K was obtained, independently from the preparation procedures. In order to improve the thermoelectric properties, mechanically alloyed SnS was doped with copper, silver, palladium, and platinum. Using silver as dopant, the efficiency could be doubled, while a tin substitution with the other elements did barely affect the thermoelectric transport. A comparison to single crystalline SnS reveals a reduced thermal conductivity through nanostructuring. The structure of the products was examined via X-ray diffraction (XRD) and transmission electron microscopy (TEM) showing a nanoscopic character with slightly varying lattice constants. In the case of larger sized impurity atoms secondary phases occur, indicating the solubility limits were reached and only partial incorporation of the added dopant amount into the matrix took place. [ABSTRACT FROM AUTHOR]

Pt nanoparticles supported on Vulcan XC-72 carbon black have been synthesized by a facile solvothermal method. The obtained Pt/C catalysts are characterized by X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), and transmission electron microscopy (TEM) analysis to identify Pt mean size and Pt content. The results of electrochemical measurements demonstrate that the Pt/C catalyst prepared at the reaction temperature of 140 °C and the reaction time of 2 h shows the biggest initial electrochemical area with an initial electrochemically active specific surface area (ESA) of 70.6 m2gPt−1, the highest electrocatalytic stability with an ESA loss of 48.7% after 1,000 CV cycles, and the best electrocatalytic activity and stability toward methanol oxidation reaction (MOR) with a specific activity of 0.6 mA cm−2 and a retention rate (the ratio of the final current density to the maximum current density) after 3,600 s of 42.8%. Moreover, the electrochemical performance of homemade Pt/C catalyst is superior to that of commercial Pt/C catalyst, suggesting that the solvothermal synthesis is a promising method for preparing Pt based catalyst. [ABSTRACT FROM AUTHOR]

Uniform CIS and CIGS nanomaterials were successfully synthesized by a simple amino-based assisted solvothermal technique using PVP-30 as the surfactant. The influence of surfactant, temperature and Ga amount on the structure, morphology, phase and spectral property was analyzed in detail. The results show that CIS and CIGS nanomaterials with 40∼70 nm in diameter can be gained at 200 °C for 24 h. PVP-30 surfactant can greatly improve the dispersion characteristics of particles. XRD pattern shows that the 'three peaks' obviously shift to bigger 2θ after gallium implantation because of lattice contraction. EDAX and Raman show that the final product is close to CuIn0.7Ga0.3Se2. The possible reaction mechanism has also been explained in detail. UV-vis-NIR spectra show that the absorption peak and absorption edge of CIGS with 1.278 eV bandgap obviously shift to a lower energy compared to CIS with 1.051 eV bandgap, which shows the potential application in enhanced conversion efficiency. [ABSTRACT FROM AUTHOR]

Monoclinic peanut-like BiVO4 products have been successfully synthesized by a solvothermal method. The volume of CH3COOH and the concentration of NH3·H2O were found to play important roles in the formation of this morphology. The optimal condition for preparation of highly active peanut-like BiVO4 samples are the volume of CH3COOH, which was 5 ml, and the concentration of NH3·H2O, which was 2 mol/L. The as-prepared samples were characterized by XRD, SEM, TEM, DRS, BET, and their photocatalytic activity was evaluated by photocatalytic decolorization of a Rhodamine B (RhB) aqueous solution under visible-light irradiation. The results demonstrated that BiVO4 with peanut-like morphology was better than that of other BiVO4 samples for photodegradation of RhB. [ABSTRACT FROM AUTHOR]

Pyrochlore-structured yttrium titanate phosphors activated by trivalent europium ions (Y2Ti2O7(YT):Eu3+), with spherical morphology, were synthesized at different pH values by a solvothermal process. From the structural and morphological measurements, the annealing temperature had no effect on the spherical morphology of the YT:Eu3+ sample. The photoluminescence excitation and emission spectra were taken by activating the Eu3+ ions in the YT host lattice as functions of Eu3+ ion concentration and annealing temperature. The optimal doping concentration was found to be 4 mol%, exhibiting an excellent orange-red emission due to the highest intensity of the 5D0 → 7F1 transition. When the YT:Eu3+ phosphor was mixed with YAG:Ce3+ phosphor, a brilliant white light emission was achieved. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

ZnO nanocrystallites have been in situ embedded in cellulose nanofibers by a novel method that combines electrospinning and solvothermal techniques. Zn(OAc)/cellulose acetate (CA) precursor hybrid nanofibers with diameter in the range of 160-330 nm were first fabricated via the electrospinning technique using zinc acetate as precursor, CA as the carrier, and dimethylformamide (DMF)/acetone(2 : 1) mixture as cosolvent. The precursor nanofibers were transformed into ZnO/cellulose hybrid fibers by hydrolysis in 0.1 mol/L NaOH aqueous solution. Subsequently, these hybrid fibers were further solvothermally treated in 180°C glycerol oil bath to improve the crystallite structure of the ZnO nanoparticles containing in the nanofibers. The structure and morphology of nanofibers were characterized by scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. It was found that hexagonal structured ZnO nanocrystallites with the size of ∼ 30 nm were dispersed on the nanofiber surfaces and within the nanofibers with diameter of about 80 nm. The photocatalytic property of the ZnO/cellulose hybrid nanofibers toward Rhodamine (RhB) was tested under the irradiation of visible light. As a catalyst, it inherits not only the photocatalytic ability of nano-ZnO, but also the thermal stability, good mechanical property, and solvent-resistibility of cellulose nanofibers. The key advantages of this hybrid nanofiber over neat ZnO nanoparticles are its elasticity, dimensional stability, durability, and easy recyclability. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

One of the major obstacles to the synthesis of nanoparticles and nanocatalyst is the stability of particles. In the present study, polymer stabilized ruthenium nanoparticles were synthesized by solvothermal method using solutions of ruthenium chloride in ethylene glycol in presence of poly( N -vinyl-2-pyrrolidone) (PVP) as a stabilizing agent. Stability of nanoparticles was studied by varying different parameters e.g. PVP/RuCl molar raio, RuCl concentration, reaction temperature and time and expressed in terms of particle size and size distribution. Transmission electron microscope (TEM) analysis revealed the presence of metallic clusters with a uniform size of about 20-65 nm. Dispersion destabilisation of colloidal nanoparticles was detected by Turbiscan. Polymer stabilized ruthenium nanoparticles were dispersed on γ-alumina to prepare uniformly disperse Ru/γ-AlO catalyst by mechanical strirring and sonication. Inductively coupled plasma-optical emission spectroscopy (ICP-OES), X-Ray powder diffraction (XRD), Transmission electron microscopy (TEM) and Thermo gravimetric analysis (TGA) were used to characterize the supported catalyst. (© 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

Silver nanorings as new and outstanding candidates for opto‐electronics applications are depicted on the cover image among the main other conductive materials. Facial and high yield preparation method for the silver nanoring and better optical properties than silver nanowires are the most important reported results. More information can be found in the Full Paper by M.‐R. Azani and A. Hassanpour on page 19195. [ABSTRACT FROM AUTHOR]

Porous magnetite (Fe3O4) nanospheres are successfully prepared through a one‐pot solvothermal method with a gas‐bubble‐assisted Ostwald ripening process. The formation mechanism is explored by studying the reaction parameters, including the concentration of the precipitating agent, capping agent, and urea gas source for a fixed reaction temperature and time. The authors' results show that the Fe3O4 nanospheres are composed of many primary nanocrystals, the sizes of which are well regulated by urea concentration. As such, the size of the spherical primary nanocrystal determines the porosity of Fe3O4 nanospheres. Strong reflection loss of −49.2 dB is observed at 11.9 GHz for highly porous Fe3O4 nanospheres with a thickness of 2.7 mm due to multiple scatterings in void spaces and increased dielectric loss caused by higher interfacial polarization relaxation loss in the porous structure. The authors believe that the prepared porous Fe3O4 nanospheres are good candidates for electromagnetic absorption applications. Porous Fe3O4 nanospheres composed of primary spherical nanocrystals are prepared through one‐pot solvothermal method by gas‐bubble assisted Ostwald ripening process. The porosity is controlled via tuning the amount of urea in the reaction process. Strong reflection loss of −49.2 dB at 11.9 GHz is observed for highly porous Fe3O4 nanospheres. This study reveals the effect of porosity on microwave absorption. [ABSTRACT FROM AUTHOR]

Up to now, there are rare reports of CoF2 spheres used as high capacity cathode materials. Herein, porous CoF2 spheres were synthesized and studied as cathode materials for LIBs. The porous CoF2 spheres were synthesized by a facile one-pot solvothermal method using a safe and inexpensive ammonium fluoride as the fluorine sources. The nature of the synthesis can avoid using corrosive fluorine sources and additional high-temperature thermal treatment. The structure, morphologies and electrochemical performance of the samples obtained at different reaction times and solvothermal temperatures were investigated. The results show that the CoF2 spheres obtained at 200 °C for 20 h show better electrochemical performances, including a high initial discharge capacity, good capacity retention and high Coulombic efficiency. It can deliver a high initial discharge capacity of 537.8 mA•h•g−1 and keep 127.4 mA•h•g−1 after 30 cycles used as cathode materials for lithium-ion batteries. The good electrochemical performances may be attributed to good crystallinity, porous structure and relatively intermediate sphere size. [ABSTRACT FROM AUTHOR]