Direct-Write Printing of Freestanding Prussian Blue Analogue Fibers with Tunable Redox Potentials
Year: 2026
Type: preprint
Abstract: Prussian blue (PB) and its analogues (PBAs) are attractive electrode materials for energy storage because of their chemical tunability, open-framework structures, fast ion transport, and rich redox chemistry. Yet, their practical implementation remains limited due to the challenging processability and the discrete set of redox potentials accessible through conventional compositions. Here, a 3D flow-focusing microfluidic strategy is used for directly synthesizing and printing freestanding PB and PBA composite fibers in a single step, coupling particle formation with their integration into an alginate/carbon-nanotube matrix. The method yields continuous, self-supporting fibers incorporating PB and multiple PBAs (Co, Ni, Cu, Zn), which can be directly written into functional electrode architectures and assembled into working energy storage cells. Beyond processability, the platform enables two complementary routes for voltage design: high-entropy PBAs, which access redox responses distinct from those of conventional single-metal PBAs, and spatially encoded fibers in which different PBAs are integrated within one fiber to generate intermediate and deliberately tuned electrochemical behavior. By exploiting the inherent spatial and temporal control afforded by microfluidic flow focusing, the approach establishes a versatile route toward printed, application-tailored PB and PBA electrodes with programmable operating voltages.
Source: ChemRxiv
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W7221536526