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Interlayer functionalization modulation is essential for modifying LDHs and improving their selectivity and adsorption capacity for target pollutants. In this work, Glu@NiFe-LDH was synthesized using a simple one-step hydrothermal method and tested for its ability to remove CrO42− from wastewater. The modification significantly increased the composite material's removal ability by 2–3 times, up to 98.36 mg g−1. The behavior of CrO42− adsorption on Glu@NiFe-LDH was further studied by adjusting the affecting factors (i.e., temperature, pH, contact time, initial concentration, and interfering substance), and the adsorption behavior was confirmed as a spontaneous and chemisorption process. And the result was that Glu@NiFe-LDH demonstrated high capacity, efficiency, stability, and selectivity for the adsorption of CrO42− in a single electrolyte and natural water containing competing anions. Furthermore, molecular dynamics simulations (NVT ensemble) were employed to further reveal the mechanism of glutamic acid modification on LDH at the microscopic scale. Additionally, the IRI analysis method revealed the mechanism of weak interaction between glutamic acid molecules and CrO42−. This study provides a detailed understanding of the intercalation mechanism involved in the amino acid modification of LDHs. It explains the adsorption mechanism of metal oxo-acid radicals by amino acid-modified LDHs from a theoretical perspective. The findings offer experiments and a theoretical basis for designing targeted adsorbents in the future. [ABSTRACT FROM AUTHOR]

Tetragonal-phase BaTiO3 powders of particle size 370 nm were synthesized by microwave sintering at 850 °C. The raw materials were BaCO3, TiO2, and alanine. SiC microspheres were used as microwave conductors. The effects of the holding time, sintering aids, and SiC addition on the preparation of BaTiO3 were investigated. The results indicate that the addition of SiC as a microwave acceptor leads to formation of microwave micro-regions. This enables uniform heating of the raw materials and decreases the calcination temperature needed to obtain BaTiO3. Alanine coordinates with Ba, and this loosens the metal–CO3 bond and promotes separation of CO2, decreases the BaCO3 decomposition temperature, and provides a higher nucleation site density. It gives an idea about the microwave solid-state synthesis of BaTiO3 powder. [ABSTRACT FROM AUTHOR]

Honeycomb nitrogen-doped porous carbon (NPC) was prepared for supercapacitor applications by hydrothermal carbonization and KOH activation process. This process used glucose as the carbon source and trans-1, 2-cyclohexane diamine tetraacetic acid as the nitrogen source. It can both control the morphology and improve the electrical performances of the as-achieved NPC. The porous carbon electrode offers improved electrochemical properties with a capacitance as high as 423 F/g at 0.5 A/g. There was excellent cycling stability with 92.5% capacitance retention after 5000 cycles at 10 A/g current density as well as good rate performance with 300 F/g even at 20 A/g. This is due to the hierarchical porous structure, high specific surface area, numerous nitrogen groups, and good electrical conductivity. Moreover, the symmetric supercapacitor based on the porous carbon materials in neat DLC301 electrolyte delivers a high energy density of 58.75 Wh/kg and an excellent power density of 250 W/kg. Two assembled supercapacitors were connected and utilized for the driving recorder to work normally for 15 s. These satisfactory electrochemical properties indicate that the honeycomb 3D porous carbon has good prospects as an electrode for supercapacitors. [ABSTRACT FROM AUTHOR]