Developing novel eco-friendly broad-spectrum visible light photocatalysts for dye removal is one of the urgent problems for water treatment. Here, copper-doped carbon dots (CDs) were reported to be directly fabricated from chromated copper arsenate (CCA) wood waste for the photocatalytic degradation of the methylene blue dye. The properties of the resulting CDs were thoroughly characterized and analyzed, preceding an investigation into the adsorption kinetics of dye degradation. The kinetic study showed that reactant concentration was the rate-limiting factor. The obtained CDs showed a 151 mg/g photocatalytic degradation capacity. Comparing pure CDs to CDs/TiO₂ composites, the former demonstrated higher photodegradation efficiency. This superiority can be attributed to the synergistic action of adsorption and photocatalytic degradation working in tandem. This study prepared Cu doped CDs and elucidated the photocatalysis mechanism of methylene blue degradation by CDs. The photodegradation of organic dyes through CDs derived from waste CCA wood emerges as an eco-friendly, facile, and highly efficient method.

This study explores lignin-retaining transparent wood biocomposite production through a lignin-modification process coupled with epoxy resin. The wood’s biopolymer structure, which includes cellulose, hemicellulose, and lignin, is reinforced with the resin through impregnation. This impregnation process involves filling the voids and pores within the wood structure with resin. Once the resin cures, it forms a strong bond with the wood fibers, effectively reinforcing the biopolymer matrix and enhancing the mechanical properties of the resulting biocomposite material. This synergy between the natural biopolymer structure of wood and the synthetic resin impregnation is crucial for achieving the desired optical transparency and mechanical performance in transparent wood. Investigating three distinct wood species allows a comprehensive understanding of the relationship between natural and transparent wood biocomposite properties. The findings unveil promising results, such as remarkable light transmittance (up to 95%) for Aspen transparent wood. Moreover, transparent wood sourced from White Spruce demonstrates excellent stiffness (E = 2450 MPa), surpassing the resin’s Young’s modulus. Also, the resin impregnation enhanced the thermal stability of natural wood. Conversely, transparent wood originating from Larch showcases superior impact resistance. These results reveal a clear correlation between wood characteristics such as density, anatomy, and mechanical properties, and the resulting properties of the transparent wood.

The flame retardancy of wood–polymer composites significantly affects their potential applications. Thus, multilayered wood flour/high-density polyethylene (HDPE)/polycarbonate (PC) composites were prepared via thermocompression to improve the fire retardancy of wood–polymer composites in this paper. Thermal degradation behavior, flame retardancy, and flexural strengths of the resulting composites were investigated using a thermogravimetric analysis, cone calorimetry, and mechanical testing machine, respectively. Results revealed that the boric acid treatment reduced the heat release rate and total heat release of the wood flour/HDPE composites and increased their mass of residues. However, boric acid reduced the flexural strength of the resulting composites. The combustion test indicated that PC cap layers suppressed the combustion of the resulting composites via the formation of carbon layers. Adding PC layers reduced heat release and increased the flexural strength of the resulting composites. Finally, the failure mode of the multilayered wood flour/HDPE/PC composites in the three-point flexural test was simulated by finite element analysis.