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[Display omitted] • Long life silver-zinc (Ag-Zn) fibrous batteries have been developed. • A bifunctional gel electrolyte is designed by introducing graphene oxide. • The undesired Zn dendrite growth and Ag migration during cycling are suppressed. • The battery can maintain its performance and power electronics under deformations. Silver-zinc (Ag-Zn) fibrous batteries are considered as a promising power source for next-generation flexible/wearable electronics because of their superior safety, high energy density, and stable output voltage. Nevertheless, the widespread application of Ag-Zn batteries is hindered by their limited cycle life, primarily caused by Zn dendrite growth and Ag migration. Herein, we develop a flexible mild Ag-Zn fibrous battery with outstanding cycle performance via designing a bifunctional gel electrolyte. The graphene oxide (GO) introduced into the electrolyte provides dual enhancement in suppressing the growth of Zn dendrite and migration of Ag, leading to improved structural integrity and long cycle life. The designed fibrous battery demonstrates a high capacity of 0.85 mAh cm−1 and it can retain 90% (77.4%) of the initial capacity after 250 cycles under current density of 0.5 (5) mA cm−1. Additionally, the battery can maintain its performance under various deformations and a four-battery set is employed as the power source for LED patterns and wearable sensors. This work provides a rational way to design advanced gel electrolytes for high-performance flexible batteries. [ABSTRACT FROM AUTHOR]

Silver nanowire (Ag NW)-based flexible and transparent electrodes are a promising candidate for various electronic and optoelectronic applications. However, thermal and electrical instabilities of Ag NW networks during operation and post treatments need to be improved for practical applications. In this work, Ag NW/Graphene Oxide (GO) hybrid films with a multilayer structure were developed, in which transparent GO sheets were inserted between Ag NWs. For the pristine Ag NW networks, contacted NWs exhibited poorer thermal stability than individual NWs as faster Ag diffusion between NWs led to the breakage of the junctions at working temperatures, hence leading to the overall device failure. In contrast, the GO intermediate layers hindered the Ag diffusion between NWs in the Ag NW/Graphene Oxide hybrid films and maintained the junction structure, giving rise to enhanced thermal stability compared to the pristine networks and the GO-covered samples. For electrical tests, unlike the network degradation under annealing treatments, a local deterioration perpendicular to the current flow was directly observed after electrical breakdown, which was attributed to high local temperature under large applied voltage. The electrical failure of the devices was related to the network structure and defects. Furthermore, the pristine devices showed notable variation of failure voltage, which in the hybrid devices is more uniform and improved in general. [ABSTRACT FROM AUTHOR]

Harvesting energy from ubiquitous moisture is attracting growing interest for directly powering electronic devices. However, it is still challenging to fabricate high-performing moisture-electric generators (MEGs) with high and stable electric output. Herein, we report a simple strategy to modify the oxygen-based groups of graphene oxide using hydrochloric acid treatment, which boosts the electric output based on the device structure of graphene oxide/polyvinyl alcohol (GO/PVA) MEGs. The resulting MEG enables a stable voltage of 0.85 V and a current of 9.28 μA (92.8 μA∙cm-2), which are among the highest values reported so far. More excitingly, electric output gets further improved by simply assembling four MEG units in series or parallel. Moreover, the MEG shows great commercial potential for flexible and wearable applications. Driven by these advancements, the assembled MEGs can successfully power sensors and calculators. This work opens a new era of advance for a new energy conversion technology able to directly powering electronic devices. Schematic illustration of graphene oxide-based MEG powering electronic devices [Display omitted] • Acidification is a facile and effective way to tune the functional group density of GO materials. • MEGs achieve one of the highest continuous electrical outputs with a voltage of 0.85 V and current density of 92.8 μA∙cm-2. • The density of C O bonds significantly affects the output, providing a guideline to select the target materials. • A commercial pressure sensor and digital calculator can be directly powered by a single MEG and MEG array, respectively. [ABSTRACT FROM AUTHOR]