Waterborne Graphene- and Nanocellulose-Based Inks for Functional Conductive Films and 3D Structures

Abstract

In the vast field of conductive inks, graphene-based nanomaterials, including chemical derivatives such as graphene oxide as well as carbon nanotubes, offer important advantages as per their excellent physical properties. However, inks filled with carbon nanostructures are usually based on toxic and contaminating organic solvents or surfactants, posing serious health and environmental risks. Water is the most desirable medium for any envisioned application, thus, in this context, nanocellulose, an emerging nanomaterial, enables the dispersion of carbon nanomaterials in aqueous media within a sustainable and environmentally friendly scenario. In this work, we present the development of water-based inks made of a ternary system (graphene oxide, carbon nanotubes and nanocellulose) employing an autoclave method. Upon controlling the experimental variables, low-viscosity inks, high-viscosity pastes or self-standing hydrogels can be obtained in a tailored way. The resulting inks and pastes are further processed by spray- or rod-coating technologies into conductive films, and the hydrogels can be turned into aerogels by freeze-drying. The film properties, with respect to electrical surface resistance, surface morphology and robustness, present favorable opportunities as metal-free conductive layers in liquid-phase processed electronic device structures.

3D-Printable Nanocellulose-Based Functional Materials: Fundamentals and Applications

“…Films fabricated from graphene- and nanocellulose-based inks and pastes with high chemical stability and no record of cytotoxicity were developed as metal-free conductive substitutes from water-based inks with potential for applications in the production of liquid-phase electronic device constructs [ 70 ]. These films presented interesting electronic properties, suggesting potential applications as a substitute for the metal-containing conductive inks for electric or optoelectronic devices such as sensors, supercapacitors, and solar cells.…”

“…Real images of a hydrogel derived from hydrothermal treatment in water ( left ) and preparation scheme of aerogels by unidirectional freezing followed by lyophilization ( right ) ( d ), used with permission from ref. [ 70 ].…”

“…Photographs of films made from low-viscosity inks (b) and high-viscosity pastes (c) on glass substrates. Real images of a hydrogel derived from hydrothermal treatment in water (left) and preparation scheme of aerogels by unidirectional freezing followed by lyophilization (right) (d), used with permission from ref [70]…”

Graphene-Oxide-Based Fluoro- and Chromo-Genic Materials and Their Applications

“…The printed hGO mesh has multiple levels of porosity from macroscale to nanoscale, which provides pathways for electrolytes and oxygen, improving the performance of Li-O 2 batteries. Gonzalez-Dominguez et al [ 101 ] prepared some water-based inks composed of a ternary system (carbon nanotubes, GO, and nanocellulose) by autoclave methods. Importantly, by controlling the experimental conditions, low-viscosity inks, high-viscosity paste, or self-standing hydrogels can be obtained.…”

Editorial for “Properties and Applications of Graphene and Its Derivatives”

“…Regarding electric or electronic applications of graphene nanocomposites, there are also excellent pieces of work in this Special Issue, such as that from Rendón-Patiño and co-workers (dealing with graphene-MoS 2 heterostructures with excellent catalytic activity towards H 2 and O 2 evolution reactions) [16], or the work by Rodríguez-Mas et al, who have successfully inserted a conductive polymer-coated reduced GO layer in an organic-based LED, increasing its current density [17]. The great potential of GO to stand as a versatile adjuvant in advanced applications is herein embodied by the works of Petris et al (GO-silicophosphate compounds for the optical limiting of femtosecond lasers) [18], and that of González-Domínguez and co-workers (dealing with aqueous inks based on GO-nanocellulose hybrids with potential to be applied in electrode manufacturing) [19].…”