Ni-Doped Ordered Nanoporous Carbon Prepared from Chestnut Wood Tannins for the Removal and Photocatalytic Degradation of Methylene Blue

Abstract

In this work, Ni-doped ordered nanoporous carbon was prepared by a simple and green one-pot solvent evaporation induced self-assembly process, where chestnut wood tannins were used as a precursor, Pluronic® F-127 as a soft template, and Ni2+ as a crosslinking agent and catalytic component. The prepared carbon exhibited a 2D hexagonally ordered nanorod array mesoporous structure with an average pore diameter of ~5 nm. Nickel was found to be present on the surface of nanoporous carbon in the form of nickel oxide, nickel hydroxide, and metallic nickel. Nickel nanoparticles, with an average size of 13.1 nm, were well dispersed on the carbon surface. The synthesized carbon was then tested for the removal of methylene blue under different conditions. It was found that the amount of methylene blue removed increased with increasing pH and concentration of carbon but decreased with increasing concentration of methylene blue. Furthermore, photocatalytic tests carried out under visible light illumination showed that purple light had the greatest effect on the methylene blue adsorption/degradation, with the maximum percent degradation achieved at ~4 h illumination time, and that the percent degradation at lower concentrations of methylene blue was much higher than that at higher concentrations. The adsorption/degradation process exhibited pseudo second-order kinetics and strong initial adsorption, and the prepared carbon showed high magnetic properties and good recyclability.

Efficient and Selective Removal of Organic Cationic Dyes by Peel of Brassica juncea Coss. var. gemmifera Lee et Lin-Based Biochar

“…For the N1s peaks, the peak corresponding to the C-N bond is located at 399.72 eV [33], and the peak corresponding to N-H is located at 400.40 eV (Figure 3b). For the O1s peaks, the peak at 532.15 eV corresponds to the C=O double bond of carbonyl group [34], and the peak at 532.62 eV corresponds to the C=O double bond, while the peak at 533.05 eV corresponds to the O-H bond of carboxyl group (Figure 3c) [35]. For the S2p peaks, the peak at 164.83 eV corresponds to S-O bond, and the peak at 163.67 eV corresponds to C-S bond.…”

Silver Nanoparticles Biosynthesized Using Cashew Nutshell Liquid (CNSL): Characterization and Methylene Blue Degradation Studies

“…For dye degradation, methylene blue -cationic azo dye -is chosen as a pollutant of interest. Dye pollution has become more abundant in our water systems due to discharge from paper, textile, leather, food, cosmetic, and pharmaceutical industries [2,[25][26][27]. Out of the roughly 2.1 metric tons of dye produced worldwide, about 15% enter our waterways, effectively decreasing the water's transparency which causes less light to reach aquatic plants [25].…”

“…This hinders photosynthesis, lowering the amount of dissolved oxygen in water, which is essential for aquatic ecosystems to support life [25,28]. Additionally, synthetic dyes are non-biodegradable and release possible carcinogenic products, [26][27][28] which makes their removal imperative for healthy water systems.…”