A wood-based composite exhibiting excellent electromagnetic shielding performance was prepared by electroless Ni plating. The properties of the material were characterized by a series of tests. The results showed that the growth route of Ni particles was first arranged along the inherent grain of the wood to form a banded metal layer. With extension of the duration of electroless plating, the growth of Ni particles gradually extended around and filled the pores between wood fibers, and finally formed flake-shape structure. The metal coatings formed a strip along the inherent grain of the wood surface and then changed into a sheet until it covered the entire wood surface. The coatings resistance was from 12 Ω to 0.5 Ω with the increase in duration of electroless plating. When the duration was 20 min, the composite coating resistance was 0.5 Ω. Here, the contact angle of composite coatings was 98.3° when the plating time was 15 min. When the wood surface was modified via two depositions of Ni, the average electromagnetic shielding value of the composites was over 80 dB in the frequency ranging from 0.3 kHz to 3.0 GHz.

In this study, all-cellulose composite materials are prepared through the dissolution and regeneration process using waste kraft papers as raw material in the sodium hydroxide/thiourea/urea solvent system. The degree of conversion is controlled by adjusting the microenvironment of the cellulose solvents, and the composite membrane is prepared by mixing the regenerated cellulose with the insoluble cellulose, which aims at adjusting the morphology and mechanical properties of the composite material. The shape of the regenerated cellulose after the dissolution and regeneration change from the original fiber into a sphere as shown by SEM images. The composite films show different phenomena, the insoluble part, and the matrix phase form a dense and strong network structure. The presence of this insoluble part increases the strength of the matrix phase and fundamentally changes the brittleness of the regenerated cellulose. This work provides a green and promising method to prepare high-performance, environmentally friendly all-cellulose composite materials.

In this study, carbon microspheres (CSn) with various oxygencontaining functional groups (−OH, −C�O, −COOR) were prepared through hydrothermal carbonization at different temperatures. The raw material is the micro-/nanocellulose prepared from factory poplar waste. Methylene blue (MB), as the model dye, was used to verify the adsorption performances. The influences of different adsorption parameters, such as adsorption time, temperature, solution pH, and ion concentration, were analyzed. The adsorption kinetics was well fitted to the pseudo-second-order model. The adsorption isotherm was better described by the Langmuir isotherm with the maximum adsorption capacity (536.64 mg g −1 ) at room temperature. Using Fourier transform infrared (FTIR), X-ray photoelectron spectroscopy (XPS), and adsorption processes, it was confirmed that the interactions between the oxygen-containing functional groups and methylene blue were the key factor affecting the adsorption. At the same time, it was further confirmed that the content of the oxygen-containing functional groups of the CSn had been relatively reduced with the increases in the temperature, and the adsorption capacity of methylene blue was also decreased. The CSn after adsorption of methylene blue were directly pyrolyzed and its electrical conductivity was also significantly improved. The conducting material not only solved the dilemma of desorption waste liquid treatment but also achieved the dual application of the materials. Therefore, CSn is considered to be a green and sustainable carbon material.

Cellulose extracted from the factory waste poplar, converted into value-added carbon spheres by hydrothermal carbonization (HTC). Oxygen-rich functional group carbon spheres with smooth morphology, good dispersibility, controllable particle size, high carbon content and high calori c value were prepared under different process conditions. The optimum process conditions for obtaining good shape are temperature 250℃, time 12h, and cellulose dosage 1g. Under these conditions, the produced carbon microspheres have smooth surface, high dispersion and uniform particles. FTIR, XPS and elemental analysis indicated that the carbon content was as high as ~ 75% with increasing temperature and time, and the theoretically calculated HHV was 29.4 MJ/kg. The H/C and O/C ratios are quite different relative to the raw materials, demonstrating that cellulose undergoes dehydration, decarboxylation and demethylation during hydrothermal carbonization to form carbon microspheres with oxygenrich functional groups. The carbon materials were analyzed by BET, TG, Raman and XRD, which further proved that the carbon microspheres are high-concentration aromatized amorphous non-porous carbon materials.