Aqueous Inks of Pristine Graphene for 3D Printed Microsupercapacitors with High Capacitance

Abstract

printing is gaining importance as a sustainable route for the fabrication of high-performance energy storage devices. It enables the streamlined manufacture of devices with programmable geometry at different length scales down to micron-sized dimensions. Miniaturized energy storage devices are fundamental components for on-chip technologies to enable energy autonomy. In this work, we demonstrate 3D printed microsupercapacitor electrodes from aqueous inks of pristine graphene without the need of high temperature processing and functional additives. With an intrinsic electrical conductivity of ∼1370 S m −1 and rationally designed architectures, the symmetric microsupercapacitors exhibit an exceptional areal capacitance of 1.57 F cm −2 at 2 mA cm −2 which is retained over 72% after repeated voltage holding tests. The areal power density (0.968 mW cm −2 ) and areal energy density (51.2 μWh cm −2 ) outperform the ones of previously reported carbon-based supercapacitors which have been either 3D or inkjet printed. Moreover, a current collector-free interdigitated microsupercapacitor combined with a gel electrolyte provides electrochemical performance approaching the one of devices with liquid-like ion transport properties. Our studies provide a sustainable and low-cost approach to fabricate efficient energy storage devices with programmable geometry.

Durable Zn-ion hybrid capacitors using 3D printed carbon composites

“…The aqueous ink based on Gr–C heterostructures was prepared using modified procedure of our earlier work. 52 Briefly, 1.4 g of Gr platelets and 0.34 g of CMC powder were added to a high density polyethelene plastic jar containing water dispersed SWCNTs (0.4 wt%, 4 mg ml −1 ). The mixture was then homogenized using a high-speed planetary mixer (Thinky ARE-250) at 2000 rpm for 5 min.…”

Advanced Three-Dimensional Microelectrode Architecture Design for High-Performance On-Chip Micro-Supercapacitors

“…Recently, using an aqueous ink consisted of pristine graphene platelets and carboxymethyl cellulose (CMC) viscosifier, Tagliaferri et al . fabricated highly conductive strut interdigitated microelectrodes (∼1370 S m –1 ) with multiple layers for MSCs (Figure a,b) . As depicted in Figure c, the side-view scanning electron microscope (SEM) image demonstrated the interconnected porous network of pristine graphene platelets after the removal of the CMC binder.…”

Transient, Biodegradable Energy Systems as a Promising Power Solution for Ecofriendly and Implantable Electronics

“…[55][56][57] Figure 2e illustrates a disposable supercapacitor (electrical double layer capacitor, EDLC) with a configuration of two half cells folded into one working device, by a direct ink writing procedure. [52] Various viscoelastic water-based inks with shear-thinning and yielding behaviors were prepared using nontoxic and renewable materials [58][59][60][61][62] : 1) nanocellulose as a rheological modifier, dispersing, and gelling agent; 2) graphite flakes and carbon-black particles dispersed in shellac for a current collector ink; and 3) carbon, graphite, nanocellulose, and water composite as electrode ink and glycerol/NaCl-nanocellulose composite as electrolytic ink. Fully printed, disposable paper supercapacitors exhibited an absolute capacitance of 61.1 mF at 1 mV s À1 , volumetric capacitance of 135 mF cm À3 , a working voltage of 1.2 V, and excellent mechanical properties with reliable cyclic behaviors.…”