Orderly arranged three-dimensional porous S/Ti3C2/NC potassiphilic scaffold enabling dendrite-free K metal deposition for potassium metal batteries

Potassium (K) metal battery is a promising future electrochemical energy storage system owing to the low electrochemical potential, high theoretical specific capacity, and inexhaustible K resources. However, the K metal anodes prematurely defeat due to the inescapable dendrites growth and volume variation, which severely hindered the practical application of K metal battery. To tackle these issues, we propose a S-modified Ti3C2-chitosan aerogel (S-TNC) with orderly arranged 3D porous structure and high potassiphilicity to construct K metal anode (S-TNC@K) by molten infusing with K metal. S-TNC scaffold buffers the internal volume variation via large porous voids during the plating/stripping, and accelerates electron/ion transport by interconnected conductive skeleton, inducing uniform K deposition. The monodispersed S and N sites in S-TNC improve the potassiphilicity of scaffold, reducing K nucleation barrier and inhibiting K dendrites growth. Benefiting from the above outstanding properties of S-TNC scaffold, the S-TNC@K//PTCDA full battery realizes excellent cycling stability with a boosted specific capacity of 90.2 mA h g−1 after 100 cycles at 1 C. This work solves the dendrites growth and volume variation problems in K metal batteries, which laid foundation for the further development of K metal battery. A novel orderly arranged 3D potassiophilic S-TNC scaffold was well-designed for the first time to construct S-TNC@K metal anode, which guarantee the uniform and dendrite-free K metal deposition, and thus achieving stable and reversible cycling property of K metal battery. [Display omitted] •We reported a novel orderly arranged 3D potassiophilic scaffold to construct K metal anode by molten infusing method.•The constructed S-TNC scaffolds exhibit the improved potassiophilicity due to the monodispersed S and N sites.•The orderly arranged 3D porous structure accommodates the deposited K metal and restrain serious volume variation.•The S-TNC scaffolds quicken electron and K ion transport kinetics to homogenize K ions flux.