Pe Justin Alfred, Mun Sung-Phil, Lee Min
Department of Wood Science and Technology, Jeonbuk National University, Jeonju 54896, Korea.
Department of Wood Products, National Institute of Forest Science, Seoul 02455, Korea.
Materials (Basel). 2021 Aug 27;14(17):4888. doi: 10.3390/ma14174888.
Fe-doped titanium dioxide-carbonized medium-density fiberboard (Fe/TiO-cMDF) was evaluated for the photodegradation of methylene blue (MB) under a Blue (450 nm) light emitting diode (LED) module (6 W) and commercial LED (450 nm + 570 nm) bulbs (8 W, 12 W). Adsorption under daylight/dark conditions (three cycles each) and photodegradation (five cycles) were separately conducted. Photodegradation under Blue LED followed pseudo-second-order kinetics while photodegradation under commercial LED bulbs followed pseudo-first-order kinetics. Photodegradation rate constants were corrected by subtracting the adsorption rate constant except on the Blue LED experiment due to their difference in kinetics. For 8 W LED, the rate constants remained consistent at ~11.0 × 10/h. For 12 W LED, the rate constant for the first cycle was found to have the fastest photodegradation performance at 41.4 × 10/h. After the first cycle, the rate constants for the second to fifth cycle remained consistent at ~28.5 × 10/h. The energy supplied by Blue LED or commercial LEDs was sufficient for the bandgap energy requirement of Fe/TiO-cMDF at 2.60 eV. Consequently, Fe/TiO-cMDF was considered as a potential wood-based composite for the continuous treatment of dye wastewater under visible light.
评估了铁掺杂二氧化钛碳化中密度纤维板（Fe/TiO-cMDF）在蓝色（450 nm）发光二极管（LED）模块（6 W）和商用LED（450 nm + 570 nm）灯泡（8 W、12 W）下对亚甲基蓝（MB）的光降解性能。分别进行了日光/黑暗条件下的吸附（各三个循环）和光降解（五个循环）。蓝色LED下的光降解遵循准二级动力学，而商用LED灯泡下的光降解遵循准一级动力学。由于动力学差异，除了蓝色LED实验外，光降解速率常数通过减去吸附速率常数进行校正。对于8 W的LED，速率常数在11.0×10⁻⁵/h保持一致。对于12 W的LED，发现第一个循环的速率常数在41.4×10⁻⁵/h时具有最快的光降解性能。在第一个循环之后，第二个到第五个循环的速率常数在28.5×10⁻⁵/h保持一致。蓝色LED或商用LED提供的能量足以满足Fe/TiO-cMDF在2.60 eV时的带隙能量需求。因此，Fe/TiO-cMDF被认为是一种潜在的木质基复合材料，可用于在可见光下连续处理染料废水。
