Hydrated lithium ions intercalated V2O5 with dual-ion synergistic insertion mechanism for high-performance aqueous zinc-ion batteries.

Li0.45V2O5·0.89H2O (LVO) was successfully synthesized by wet-mixing of LiOH·H2O and V2O5, with subsequent hydrothermal method for the first time. The hydrated lithium ions as the intercalated guest species were inserted into the V2O5 interlayer. The as-obtained LVO with a stable lamellar structure, enlarged interlayer space, weak interlayer repulsive force and low molecular weight, which shows a specific capacitance of 403 mAh g-1 at 0.1 A g-1, excellent rate capability and longlifespan with capacity retention of 86% over 1000 cycles at 10 A g-1. Furthermore, the LVO-based AZIBs possess a synergistic insertion mechanism of Zn2+ and H+, that is the reason for its superior performance. This work provides an efficient design strategy for synthesizing advanced cathode materials for the high-performance Zn2+ energy storage system.

Chemical adsorption of oxytetracycline from aqueous solution by modified molecular sieves.

The removal of oxytetracycline (OTC) from aqueous solution on modified molecular sieve via adsorption was investigated in the present work. The copper(II) modified molecular sieve had the much higher adsorbed amount than unmodified one. The bigger pore, the more adsorption sites benefitted for the adsorbed amount of OTC. The exchanged amount of copper(II) and the acid-base property of solution were important factors influencing the removal efficiency. The adsorption kinetics, the adsorption isotherm, the adsorption thermodynamics and the proposed adsorption mechanism were studied. The analysis of adsorption isotherm indicated it is a monolayer adsorption. The fitting with adsorption kinetics, pseudo-second-order model, deduced chemical adsorption is the main rate controlling step. And the new formation of Cu-O chemical bond and the changes at bands of N-H vibration and C-N vibration by Fourier transform infrared spectrometer further confirmed the proposal adsorption mechanism was the chemical complexation of copper(II) in modified 13X with NH2 group of OTC. As the real exchanged amount of copper(II) was 149.07 mg·g-1 and the solution pH 7.0, the adsorption capacity of modified 13X for OTC reached the maximum of 2,396 mg·g-1 (with the initial concentration of 1,000 mg·L-1).

Ordered mesoporous NiO with thin pore walls and its enhanced sensing performance for formaldehyde.

A class of formaldehyde (HCHO) gas sensors with a high response were developed based on ordered mesoporous NiO, which were synthesized via the nanocasting route by directly using mesoporous silica as the hard template. A series of mesoporous NiO with different textural parameters such as specific surface area, pore size, pore wall thickness were achieved by selecting mesoporous silica with different pore sizes as templates. The gas sensing properties for formaldehyde (HCHO) of the NiO specimens were examined. The results show that this mesoporous NiO possesses a much higher response to HCHO even at low concentration levels than the bulk NiO, and a larger specific surface area and pore size as well as thinner pore walls would be beneficial for enhancing the sensing properties of NiO.