Conductive Bacterial Cellulose Research Articles

Development of conductive bacterial cellulose foams using acoustic cavitation

Development of conductive bacterial cellulose foams using acoustic cavitation

Tough and flexible poly(dimethylsiloxane) elastomer reinforced by conductive bacterial cellulose frameworks for high-performance microwave absorber

Tough and flexible poly(dimethylsiloxane) elastomer reinforced by conductive bacterial cellulose frameworks for high-performance microwave absorber

Electro-polymerized polyaniline modified conductive bacterial cellulose anode for supercapacitive microbial fuel cells and studying the role of anodic biofilm in the capacitive behavior

Polyaniline modified conductive bacterial cellulose (BC-CNT-PANI) membrane is proposed as a novel bioanode for microbial fuel cell (MFC). BC is coated with CNT by vacuum filtering to form a conductive electrode (BC-CNT). Then the conductive side is coated with PANI through a fast and easy electro-polymerization (BC-CNT-PANI). Both anode electrodes are studied in supercapacitive MFCs (SCMFCs) by impedance analysis before and after biofilm formation on their surface. By bacteria colonization on the anodes’ surface, charge transfer resistance (Rct) of BC-CNT increases significantly from 14.5 Ω to 72 Ω while for BC-CNT-PANI, Rct decreases by 50%. Also, after biofilm formation, BC-CNT-PANI achieves a capacitance two times higher than that of BC-CNT. The SCMFCs are assembled and tested with BC-CNT, BC-CNT-PANI, and the double-anode BC-CNT& BC-CNT-PANI. Polarization, power density and galvanostatic discharge tests imply on an improvement in the SCMFC performance by using BC-CNT-PANI. The performance of the SCMFCs are limited by the anodes. The power density improves by 20% with the PANI-modified anode compared to the BC-CNT.

Carboxymethyl Cellulose (CMC) as a Template for Laccase-Assisted Oxidation of Aniline.

Polyaniline (PANi) is a conducting polymer which has been subject of intensive research on the exploitation of new products and applications. The main aim of the work is the development of a conductive bacterial cellulose (BC)-based material by enzymatic-assisted polymerization of aniline. For this, we study the role of carboxymethyl cellulose (CMC) as a template for the in situ polymerization of aniline. Bacterial cellulose was used as the supporting material for the entrapment of CMC and for the in situ oxidation reactions. The amount of CMC entrapped inside BC was optimized as well as the conditions for laccase-assisted oxidation of aniline. The new oligomers were evaluated by spectrometric techniques, namely 1H NMR and MALDI-TOF, and the functionalized BC surfaces were analyzed by thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and reflectance spectrophotometry. The conductivity of the developed materials was evaluated using the four-probe methodology. The oligomers obtained after reaction in the presence of CMC as template display a similar structure as when the reaction is conducted only in BC. Though, after oxidation in the presence of this template, the amount of oligomers entrapped inside BC/CMC is considerably higher conferring to the material greater electrical conductivity and coloration. The use of CMC as a template for aniline oxidation on BC seems to be a promising and cheap strategy to improve the yield of functionalization and increment the properties of the materials, namely electrical conductivity and coloration.

Anode-Driven Controlled Release of Cathodic Fuel via pH Response for Smart Enzymatic Biofuel Cell.

SummaryEnzymatic biofuel cells (EBFCs) with or without a membrane to separate the anodic and cathodic compartments generally suffered from high internal resistance or interactive interference, both of which restricted the improvement of their performance. Herein, a smart membrane-less EBFC was engineered based on anode-driven controlled release of cathodic acceptor via pH-responsive metal-organic framework ([Fe(CN)6]3-@ZIF-8) nanocarriers. The glucose anodic oxidation would produce gluconic acid accompanied by the change in pH value from neutral to the acidic case, which could drive the degradation of [Fe(CN)6]3-@ZIF-8 nanocarriers and further realize the controlled release of cathodic acceptor [Fe(CN)6]3-. More importantly, compared with controlled EBFC with or without membrane, the power output of the as-proposed EBFC enhanced at least 700 times due to the seamless electronic communication. Therefore, the ingenious strategy not only realized the successful engineering of the membrane-less EBFC but also provided an appealing idea for constructing smart devices.

Valorization of sugarcane straw to produce highly conductive bacterial cellulose / graphene nanocomposite films through in situ fermentation: Kinetic analysis and property evaluation

Abstract Bacterial cellulose based nanocomposites have found a growing interest in recent decades due to their impressive inherent characteristics with potential applications in diverse sectors. However, there remain several challenges due to increased production cost, lower yield, and sustainability or biocompatibility issues after chemical-based modifications. This study demonstrates the fabrication of bacterial cellulose-reduced graphene oxide films via in-situ fermentation approach using abundantly available agricultural waste (sugarcane straw) as a feedstock. The presence of reduced graphene oxide at different concentrations in culture media, significantly altered the fermentation kinetics, as evident from kinetic parameter and yield coefficients. Higher yields of bacterial cellulose-reduced graphene oxide nanocomposites, with presence of strongly integrated network-like structures between bacterial cellulose nanofibers and reduced graphene oxide nanosheets were observed at 2 wt % reduced graphene oxide loadings. Formation of such percolated networks was confirmed from improved mechanical properties and enhanced electrical conductivity, through both experimental and modeling investigations. The proposed in-situ fermentation technique to produce highly conductive bacterial cellulose-reduced graphene oxide films provides an alternative approach to meet the growing demands of biomass-derived renewable and sustainable biomaterials with commercial significance.

A novel single-enzymatic biofuel cell based on highly flexible conductive bacterial cellulose electrode utilizing pollutants as fuel

Enzymatic biofuel cell (EBFC) uses enzymes to convert the chemical energy of renewable biofuels into electrical energy, which shows great promise in the continuous power supply of implantable devices. Meanwhile, integrating carbon nanotubes (CNTs) with high conductivity and superior structural properties of bacterial cellulose (BC) as backbone to construct CNTs-BC based nanocomposites has proven to be an effective strategy. Herein, a highly flexible electrode of amidoxime-modified BC (AOBC)/carboxylated multi-walled CNTs (c-MWCNTs) were prepared by vacuum filtration with excellent laccase (LAC) immobilization. Subsequently, we developed a novel EBFC that intramolecular electron transfer was achieved by an alternative pathway for generating electricity within a single enzyme molecule of LAC. Sufficient power was efficiently extracted from unconventional fuels in single-LAC biofuel cells, including persistent pollutants (e.g., bisphenol A, hydroquinone and pyrocatechol). The open circuit voltage generated by EBFC was 0.14 V and the power density reached 1.897 W m−3. This novel single-enzymatic biofuel cell exhibited a potential for recycling of waste water as fuel.

Conductive bacterial cellulose by in situ laccase polymerization of aniline.

Conductive and colored bacterial cellulose (BC) was developed by entrapment of polyaniline (PANi) onto dry BC membranes. The polyaniline was produced by in situ green polymerization of aniline by Myceliophthora thermophila laccase at pH = 4, 25°C, in the presence of a mediator, 1-hydroxybenzotriazol (HBT), using two different reactors, a water bath (WB) and an ultrasonic bath (US). MALDI-TOF and 1H NMR characterization of the experiment solutions confirmed the efficient polymerization of aniline by laccase. The dried BC membranes with entrapped polyaniline showed electrical conductive behavior and strong coloration, opening novel routes for the exploitation of functionalized bacterial cellulose as a green material for technical textiles, wearables, and other applications.

Metal-organic frameworks governed well-aligned conducting polymer/bacterial cellulose membranes with high areal capacitance

Conductive bacterial cellulose (BC) membranes are a fascinating class of lightweight and flexible electrodes for electrochemical energy storage. Herein, we demonstrate a simple and efficient method to prepare polypyrrole (PPy)-coated BC electrodes via a template-sacrificing polymerization. Polydopamines serve as the interfacial modifier for the engagement of ZIF-67 polyhedrons along the BC nanofibers. Subsequent metal-organic frameworks-template sacrificing polymerization results in well-ordered PPy alignments along BC nanofibers to afford recovered electrolyte accessible channels. The binder-free electrode exhibits a high areal capacitance of 1.71 F cm−2 (0.4 mA cm−2) and an excellent capacitance retention of 59.8% at 20 mA cm−2. We further use the electrodes to assemble a flexible symmetric supercapacitor, which shows an areal energy density of 89.8 μWh cm−2 at a power density of 0.31 mW cm−2. This work holds great promise in fabricating flexible electrodes for portable energy storage devices.

Oxygen vacancy modulated Ti2Nb10O29-x embedded onto porous bacterial cellulose carbon for highly efficient lithium ion storage

Rational design & modulation of ion/electron transfer paths are critical for achieving high-performance anode materials for lithium ion batteries. In this work, we first time realize smart assembly of oxygen vacancy modulated titanium niobium oxide (Ti2Nb10O29-x, TNOx) onto highly conductive bacterial cellulose carbon (BCC) forming BCC/TNOx electrode through a facile solvothermal-annealing method. BCC consists of interlinked (N, S & P) co-doped carbon fibres uniformly decorated with TNOx nanoparticles. Impressively, the introduction of oxygen vacancy can effectively enhance the internal ion/electron transfer in TNOx and enhancement effect is elaborated by synchrotron radiation technology (XANES and XAFS) and DFT calculation. Meanwhile, with the aid of conductive BCC skeleton, the external ion/electron transfer path on TNOx is also greatly improved leading to better reaction kinetics. The synergistic dual internal plus external modulation on transfer path show positive advantages including smaller band gap with better electrical conductivity, and larger lattice parameters with faster ion/electron transfer. Accordingly, the BCC/TNOx electrode is endowed with outstanding lithium ion storage performance with high-rate capability (281 mA h g−1 at 5 C, and 160.5 mA h g−1 at 40 C). Our finding provides valuable insights into design of other advanced electrodes via dual transfer path modulation strategy.

A highly flexible self-powered biosensor for glucose detection by epitaxial deposition of gold nanoparticles on conductive bacterial cellulose

An Enzyme (glucose/O2) BioFuel Cell (EBFC) was developed using glucose oxidase (GOx)-based bioanode and a laccase (Lac)-based biocathode with carboxylic multi-walled carbon nanotubes (c-MWCNTs) and gold nanoparticles (AuNPs)-modified bacterial cellulose (BC) electrode as the substrate. The open circuit potential (OCP) of the EBFC was inhibited and later activated by the self-powered electrochemical device. The device not only provided high power density (345.14 µW cm−3), but also exhibited an unprecedented broad linear dynamic range from 0 to 50 mM with a lower detection limit of 2.874 μM for glucose concentrations in biological media. This result was attributed to a synergistic mechanism between the enzymes, c-MWCNTs, and AuNPs in which direct electron transfer (DET) was facilitated from the catalytic centers of enzymes to the electrode surface. The BC-based nanocomposites may have great promise as flexible electrodes in the field of self-powered biosensors.

Development of Conductive Bacterial Cellulose Composites: An Approach to Bio-Based Substrates for Solar Cells

Development of Conductive Bacterial Cellulose Composites: An Approach to Bio-Based Substrates for Solar Cells

Flexible conductive nanocellulose combined with silicon nanoparticles and polyaniline

Here we describe a unique conductive bacterial cellulose (BC) composite with silicon nanoparticles (SiNPs) and polyaniline. BC was used as a template for binding SiNPs resulting in a very promising anode material for Li-ion rechargeable batteries that showed a high specific capacity. The surfaces of the SiNPs were modified with phytic acid to enhance the binding of aniline monomer to the surface. A conformal coating of polyaniline (PANi) was formed on the modified SiNPs by in situ polymerization of aniline monomers. We also found that the phytic acid on the SiNPs was critical to ensure encapsulation of SiNPs with PANi. In addition, the phosphoric acid-tagged surface of the SiNPs enhanced the adhesion of SiNPs to the BC fibers. The resulting three dimensional network of BC was flexible and provided stress dissipation in the conductive BC composites. Flexural testing of conductive BC composites showed stable electrical conductivity even after repetitive bending over 100 times.

Electrically conductive bacterial cellulose composite membranes produced by the incorporation of graphite nanoplatelets in pristine bacterial cellulose membranes

Graphite nanoplatelets (GNPs) were utilized to improve the electrical conductivity of pristine bacterial cellulose (BC) membranes. By physical and chemical methods, flake-shaped GNPs, weaving through the surface layer of web-like cellulose nanofibrils, were indeed fixed or trapped by the adjacent nanofibrils in the BC surface network, for comparison, rod-shaped multi-walled carbon nanotubes (MWCNTs) were homogeneously inserted into BC membrane through the pore structures and tunnels within the BC membrane. Strong physical and chemical interaction exists between the BC nanofibrils and the particles of GNP or MWCNT even after 15 h sonication. BC membrane with 8.7 wt% incorporated GNPs reached the maximum electrical conductivity of 4.5 S/cm, while 13.9 wt% MWCNT/BC composite membrane achieved the maximum electrical conductivity of 1.2 S/cm. Compared with one dimensional (1-D) MWCNTs, as long as GNPs inserted into BC membranes, the 2-D reinforcement of GNPs was proven to be more effective in improving the electrical conductivity of BC membranes thus not only break the bottleneck of further improvement of the electrical conductivity of BC-based composite membranes but also broaden the applications of BC and GNPs.

Amphiphilic comb-like polymer for harvest of conductive nano-cellulose

In this study, electrically conductive bacterial cellulose (BC) was prepared by culturing Gluconacetobacter xylinus in a carbon nanotube (CNT)-dispersed medium. The CNTs were dispersed by adopting a non-covalent approach in the presence of non-ionic amphiphilic comb-like polymer (CLP). Specifically, the hydrophobic backbone of CLP was chemophysically attached to the surface of the CNTs and the hydrophilic side chains were released freely toward the medium in an aqueous environment. CLP-modified CNTs were stable and did not show any noticeable sediment, even after centrifugation at 15,000rpm for 30min. Notably, the dispersion solution of CLP-modified CNTs was stable at room temperature for several months because the long-range entropic repulsion among polymer-decorated tubes acted as a barrier to aggregation. The morphology of the BC membrane was studied by field-emission scanning electron microscopy. The presence of CLP bound to the CNT surface was characterized by Fourier transform infrared spectroscopy and the conductivity of the CNT-incorporated BC membrane was measured by four-probe measurements.

Electrically Conductive Bacterial Cellulose by Incorporation of Carbon Nanotubes

Electrically conducting polymeric membranes were prepared by incorporating multiwalled carbon nanotubes (MWCNTs) into bacterial cellulose pellicles produced by Gluconacetobacter xylinum. The MWCNTs were dispersed in a surfactant (cationic cetyl trimethylammonium bromide) solution, and cellulose pellicles were dipped into the solution for 6, 12, and 24 h. The surfactants were then extracted in pure water and dried. Electron microscopy showed that the individual MWCNTs were strongly adhered to the surface and the inside of the cellulose pellicle. The conductivity of the MWCNTs-incorporated cellulose pellicle, as measured by a four-probe at room temperature, was 1.4 x 10(-1) S/cm, based on the total cross-sectional area (approximately 9.6 wt % of MWCNTs). This suggests that the MWCNTs were incorporated uniformly and densely into the pellicles.