0 mL of NaOH (4 mol·L−1) solution was dropped into the above mixed solution under vigorous magnetic stirring at room temperature, with the molar ratio of FeCl3/H3BO3/NaOH as 2:3:4. After 5 min of stirring, 26.4 mL of the resultant brown slurry was transferred into a Teflon-lined stainless steel autoclave with a capacity of 44 mL. The autoclave was sealed and heated to 90°C to 210°C (heating rate 2°C·min−1) and kept under an isothermal condition for 1.0 to 24.0 h, and then cooled down to room temperature naturally. The product was filtered, washed with DI water for selleck three times, and finally dried at 80°C for 24.0 h for further characterization. To evaluate the effects of the molar ratio of
the reactants, the molar ratio of FeCl3/H3BO3/NaOH was altered within the range of 2:(0–3):(2–6), with other conditions unchanged. Evaluation of the hematite nanoarchitectures as the anode materials for lithium batteries The electrochemical evaluation of the Fe2O3 NPs and nanoarchitectures as anode materials for lithium-ion batteries were carried out using CR2025 coin-type cells with lithium foil as the counter electrode, microporous
polyethylene (Celgard 2400, Charlotte, NC, USA) as the separator, and 1.0 mol·L−1 LiPF6 dissolved in a mixture of ethylene carbonate, diCHIR98014 manufacturer methyl carbonate, ethylene methyl carbonate (1:1:1, by weight) as the electrolyte. All the assembly processes were conducted in an argon-filled glove box. For preparing Adriamycin mouse working electrodes, a mixed slurry of hematite, carbon black, and polyvinylidene fluoride with a mass ratio of 80:10:10 in N-methyl-2-pyrrolidone solvent was pasted on pure Cu foil with a blade and was dried at 100°C for 12 h under vacuum conditions, followed by pressing at 20 kg·cm−2. The galvanostatic discharge/charge measurements were performed at different current densities in the voltage range of 0.01 to 3.0 V on a Neware battery testing system (Shenzhen, China). The specific capacity was calculated based on the mass of hematite. Cyclic voltammogram measurements were performed on a Solartron
Analytical 1470E workstation (Farnborough, UK) at a sweep rate of 0.1 mV·s−1. Characterization The crystal structures of the samples were identified using an X-ray powder diffractometer (XRD; D8-Advance, Bruker, Karlsruhe, Germany) with a Cu Kα radiation (λ = 1.5406 Å) and a fixed power source (40.0 kV, 40.0 mA). The why morphology and microstructure of the samples were examined using a field-emission scanning electron microscope (SEM; JSM 7401 F, JEOL, Akishima-shi, Japan) operated at an accelerating voltage of 3.0 kV. The size distribution of the as-synthesized hierarchical architectures was estimated by directly measuring ca. 100 particles from the typical SEM images. The N2 adsorption-desorption isotherms were measured at 77 K using a chemisorption-physisorption analyzer (Autosorb-1-C, Quantachrome, Boynton Beach, FL, USA) after the samples had been outgassed at 300°C for 60 min.