Facile synthesis of iminated lignin for enhanced free radical and lead ion scavenging capabilities.

Kraft lignin (KL) holds significant potential as a renewable resource for the development of innovative materials that are currently not fully utilized. In this study, a novel iminated lignin (IL) was synthesized by grafting primary amine lignin (N-KL) onto salicylaldehyde. The effects of the dosage and reaction temperature on the nitrogen content of N-KL were evaluated. The maximum nitrogen content in N-KL reached to 3.32 %. Characterization by spectroscopy techniques (FT-IR, XPS, and NMR), elemental analysis, and gel permeation chromatography confirmed the imination of lignin. Additionally, the antioxidant activity of the lignin samples was investigated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability. Moreover, the DPPH radical scavenging capacity of IL-6 (IC50 = 38.6 ± 3.9 µg/mL) was close to that of commercial antioxidant butylated hydroxytoluene (BHT) (IC50 = 37.7 ± 4.5 µg/mL). Furthermore, the adsorption equilibrium results indicated that IL-6 had a maximum uptake of 115.6 mg/g Pb2+, which was 3.2-fold higher than that of KL. Kinetic adsorption experiments suggested that IL-6 adsorption follows a pseudo-second-order model. Therefore, the synthesized iminated lignin is a promising candidate for the development of environmentally friendly materials with applications as an antioxidant and lead-ion adsorbent.

Capillary-Force-Pattern Formation of Indium-Zinc-Oxide Thin-Film Transistor.

Studies of the pattern-formation technique used with solution-processed oxide thin-film transistors (TFTs) continue to explore its uses as an efficient manufacturing method. However, research remains to be completed to achieve high performance and to apply the refined technique to various current industrial technologies. We studied the patterning technique of solution-processed indiumzinc-oxide (IZO) by using the capillary-force phenomenon, the method of controlling the pattern of the IZO semiconductor layer, and approaches to reducing problems such as the cracking that occurs during patterning. The device we fabricated was filled uniformly with droplets in the capillary-force pattern. It showed a high current-on/current-off ratio, high mobility, low threshold voltage, and low subthreshold slope. Consequently, this paper demonstrates a strategy that uses the capillary-forcepattern technique to exceed the performance of traditional fabrication techniques in managing the electrical properties of solution-processed oxide TFTs.