Colloidal dispersions with liquid crystallinity hold great promise for fabricating their superstructures. As an example, when graphene oxide (GO) sheets are assembled in the liquid crystalline state, they can turn into ordered macroscopic forms of GO such as fibers via the wet spinning process. Here, we report that by reinforcing intersheet interactions, GO liquid crystals (LCs) turn into mechanically robust hydrogels that can be readily drawn into highly aligned fibrillar structures. GO hydrogel fibers with highly aligned sheets (orientation factor, f = 0.71) exhibit more than twice the ionic conductivity compared to those with partially aligned structures (f = 0.01). The hierarchically interconnected two-dimensional nanochannels within these neatly aligned GOLC hydrogel fibers may facilitate controlled transport of charge carriers and could be potentially explored as cables for interconnecting biosystems and/or human-made devices.

High torsional strength fibers are of practical interest for applications such as artificial muscles, electric generators, and actuators. Herein, we maximize torsional strength by understanding, measuring, and overcoming rheological thresholds of nanocarbon (nanotube/graphene oxide) dopes. The formed fibers show enhanced structure across multiple length scales, modified hierarchy, and improved mechanical properties. In particular, the torsional properties were examined, with high shear strength (914 MPa) attributed to nanotubes but magnified by their structure, intercalating graphene sheets. This design approach has the potential to realize the hierarchical dimensional hybrids, and may also be useful to build the effective network structure of heterogeneous materials.

Graphene quantum dots (GQDs) have gained great interest due to their chemical stabilities, unique catalytic activities, and feasible chemical functionalization opportunities; these have opened up new applications in the fields of chemical energy conversion and storage. Herein, we synthesized iron(II) phthalocyanine (FePC)–GQD conjugates as facile electrocatalysts for the enhanced oxygen reduction reaction (ORR), which is critical in energy conversion systems of fuel cells. This unique combination of materials (GQD–FePC) exhibits a greatly enhanced onset potential via a four-electron pathway in an alkaline electrolyte. Moreover, the synthesized electrocatalyst shows distinguished tolerance toward methanol and carbon monoxide, which paves the way for its commercialization as an electrocatalyst.