Layer-by-Layer Fabrication of High-Performance Broadband Anti-reflection Coatings Comprising Oppositely Charged Nanosheets and Nanoparticles

In this study, we fabricated broadband anti-reflection coatings using a method based on layer-by-layer self assembly of positively charged layer double hydroxide (LDH) nanosheets and negatively charged silica nanoparticles via electrostatic interaction. Scanning electron microscopy and atomic force microscopy were used to observe the morphology, structure, and surface topography of LDH/SiO2 multilayer coatings. The anti-reflection properties of the coatings were investigated by UV visible spectrophotometry. Glass substrates covered with the LDH/SiO2 multilayer coatings exhibited broadband anti-reflection properties. The obtained [LDH(0.4 g/L)/SiO2(25 nm)]8, [LDH(0.4 g/L)/SiO2(50 nm)]10, and [LDH(0.8 g/L)/SiO2(25 nm)]6 coatings exhibited the best broadband anti-reflection properties among the as-prepared LDH/SiO2 multilayer coatings with different deposition cycles. Transmission levels of 97% were achieved in these optimal systems. Moreover, a maximum transmittance of 98% was achieved at a wavelength of 550 nm in the [LDH(0.4 g/L)/SiO2(25nm)]8 system and at 700 nm in the [LDH(0.8 g/L)/SiO2(25nm)]6 system. Different packing patterns of the two oppositely charged nanomaterials (dense packing of LDH nanosheets and loose stacking of silica nanoparticles) and the moderate textured surface of the coatings contributed to the enhanced light transmission and reduced wavelength dependence in the UV visible spectral range

Development of a Novel Terpolymer as a Green and Efficient Decalcifying Agent for Crude Petroleum

A novel environmental decalcifying agent was prepared with allylpolyethoxy amino carboxylate (APEAA), hydroxyethyl acrylate (HEA), and maleic anhydride (MA) by means of free-radical polymerization in an aqueous solution. The morphology and structure of the samples were characterized through scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectrometry, and ¹H nuclear magnetic resonance (¹H NMR) spectra. The molecular-weight distribution of APEAA–HEA–MA was determined by the gel permeation chromatography method. APEAA–HEA–MA was used as a green decalcifying agent to remove calcium from crude petroleum, and the impact of factors such as monomer ratio, copolymerization time, dosages, and desalination temperature was analyzed. It is found that the decalcification rate of APEAA–HEA–MA could reach to its maximum, and the calcium removal efficiency was approximately 97.88% when the monomer molar ratio of APEAA–HEA–MA was 1:2:5, the reaction time of copolymerization was 2 h, the dosage was 100 ppm, and the desalination temperature was 100 °C. This research work can promote the exploration on facile synthesis of a novel terpolymer and its potential application in refinery desalting processes