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Bacterial cellulose (BC) nanofiber-supported polyaniline (PANI) nanocomposites have been synthesized via in situ polymerization of aniline onto BC nanofibers scalfold. Optimized preparation conditions were employed to achieve higher conductivity. The resultant BC/PANI nanocomposites were fully characterized in terms of structure, morphology, and thermal stability. The flake-like morphology of BC/PANI nanocomposites was observed using a field-emission gun scanning electron microscope. By manipulating the ordered flake-type nanostructure, BC/PANI nanocomposites achieved outstanding electrical conductivity as high as 5.1 S/cm. The as-prepared BC/PANI nanocomposites demonstrated a mass-specific capacitance of 273 F/g at 0.2 A.g −1 current density in supercapacitor application, the highest value reported so far for polymer-supported PANI composites.

Bacterial cellulose (BC) nanofibers were biosynthesized by Acetobacter xylinum NUST5.2, and displayed a remarkable capability for orienting TiO(2) nanoparticle arrays. Large quantities of uniform BC nanofibers coated with TiO(2) nanoparticles can be easily prepared by surface hydrolysis with molecular precision, resulting in the formation of uniform and well-defined hybrid nanofiber structures. The mechanism of arraying spherical TiO(2) nanoparticles on BC nanofibers and forming well-defined, narrow mesopores are discussed in this paper. The BC/TiO(2) hybrid nanofibers were used as photocatalyst for methyl orange degradation under UV irradiation, and they showed higher efficiency than that of the commercial photocatalyst P25.

As CO 2 emissions are sharply increasing, processes for converting CO 2 into value-added products are becoming more desirable. Ruthenium-based catalysts are the most active for CO 2 methanation; however, their substantially higher cost relative to transition metals makes them prohibitive for industrial application. In this study, we demonstrate porous hexagonal boron nitride (pBN) supports (an ideal support material for thermocatalysts due to the high thermal stability and conductivity) to improve the utilization of Ru and simultaneously enhance the catalytic activity and selectivity for CO 2 methanation. A simple vacuum filtration process is proposed that allows the Ru precursor to quickly locate the defects of pBN, where atomic Ru can be restricted onto the defects via B, N coordination through an annealing treatment. The B and N coordinations reduce the valence state of atomic Ru. The as-prepared catalyst with low Ru loading (0.58 wt %) exhibits CH 4 selectivity up to 93.5%, catalytic stability after 110 h, and a higher reaction rate [1.86 mmol CO 2 /(g cat s)] at 350 °C and 1.0 MPa compared to other nanoparticle catalysts. Both atomic-scale size and low valence state of atomic Ru supported on pBN are responsible for the improvement of CH 4 production rate as confirmed by density functional theory simulation.

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Bacterial cellulose (BC) production by Acetobacter xylinum NUST4.1 was carried out in the shake flask and in a stirred-tank reactor by means of adding sodium alginate (NaAlg) into the medium. When 0.04% (w/v) NaAlg was added in the shake flask, BC production reached 6.0 g/l and the terminal yield of the cellulose was 27% of the total sugar initially added, compared with 3.7 g/l and 24% in the control, respectively. The variation between replicates in all determinations was less than 5%. During the cultivation in the stirred-tank reactor, the addition of NaAlg changed the morphology of cellulose from the irregular clumps and fibrous masses entangled in the internals to discrete masses dispersing into the broth, which indicates that NaAlg hinders formation of large clumps of BC, and enhances cellulose yield. Because the structure of cellulose is changed depending on the culture condition such as additives, structural characteristics of BC produced in the NaAlg-free and NaAlg medium are compared using scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD). SEM photographs show some differences in reticulated structures and ribbon width and FT-IR spectra indicate that there is the hydrogen bonding interaction between BC and NaAlg, then X-ray diffraction (XRD) analysis reveals that BC produced with NaAlg-added has a lower crystallinity and a smaller crystalline size. The results show that enhanced yields and modification of cellulose structure occur in the presence of NaAlg.

CBC is applied as a framework for sulfur and an interlayer in Li–S batteries. The interlayer could prevent sulfur over-aggregation on the cathode.

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