Highly Potassiophilic Graphdiyne Skeletons Decorated with Cu Quantum Dots Enable Dendrite‐Free Potassium‐Metal Anodes

Abstract

Employing an Al foil current collector at the potassium anode side is an ideal choice to entail low‐cost and high‐energy potassium‐metal batteries (PMBs). Nevertheless, the poor affinity between the potassium and the planar Al can cause uneven K plating/stripping and, hence, an undermined anode performance, which remains a significant challenge to be addressed. Herein, a nitrogen‐doped carbon@graphdiyne (NC@GDY)‐modified Al current collector affording potassiophilic properties is proposed, which simultaneously suppresses the dendrite growth and prolongs the lifespan of K anodes. The thin and light modification layer (7 µm thick, with a mass loading of 500 µg cm−2) is fabricated by directly growing GDY nanosheets interspersed with Cu quantum dots on NC polyhedron templates. As a result, symmetric cell tests reveal that the K@NC@GDY‐Al electrode exhibits an unprecedented cycle life of over 2400 h at a 40% depth of discharge. Even at an 80% depth of discharge, the cell can still sustain for 850 h. When paired with a potassium Prussian blue cathode, the thus‐assembled full cell demonstrates comparable capacity and rate performance with state‐of‐the‐art PMBs.

Coupling Low‐Tortuosity Carbon Matrix with Single‐Atom Chemistry Enables Dendrite‐Free Potassium‐Metal Anode

“…Also, this attractive cycling performance is either comparable to or superior to most previously reported values for K anode stabilized by different strategies in various electrolytes (Figure 4g). [21,22,24,25,31,43,[46][47][48][49][50][51][52][53][54] Importantly, a similar result holds in the EMC-based electrolyte used. The SA-Co@HC/K exhibits superior performance and advanced reaction kinetics than bare K, which further indicates the effectiveness of SA-Co@HC/K composite electrode design in the different electrolytes on the suppression of K dendrites (Figures S26 and S27, Supporting Information).…”

“…[40] Except for the presence of CoN x C species in the SA-Co@HC, the N doping configuration of both HC and SA-Co@HC from the N 1s XPS spectra can be deconvoluted into four nitrogen dopants contributions, including pyridinic-N, pyrrolic-N, graphitic-N, and oxidized-N (Figure 2e and Figure S10, Supporting Information). It was reported that the potassiophilic nitrogen functional sites show large binding energy and stronger adsorption ability for K ion, [29,31,41] which is conducive to regulating the K nucleation and growth property. Overall, all these characterizations confirm the ideal design of envisaged structure.…”

“…Also, optimizing the host's K affinity has been recognized as one of the most important factors that guide K nucleation behavior. [21,31] This is because conductive K, in principle, could deposit randomly at any location inside the conductive host due to the slow nucleation kinetics, which causes uncontrollable dendrite growth. Previous studies indicated that the downsizing nucleation site dimensions to atomic levels (such as single-atom Ni and Sn) while spatially confined inside a host maximized not only the utilization of active sites, but also lead to the heterogenous seeded growth of Li and/or Na on carbon hosts.…”

In situ formed uniform and elastic SEI for high-performance batteries

“…2c and Table S1, ESI †). [28][29][30][31][32][33][34][35][36][37][38][39][40] When the current density was 0.1 mA cm À2 , the symmetric battery with 1 M AVIMFSI also cycled for more than 5000 h. The rate performance of symmetric batteries with 1 M AVIMFSI electrolyte is shown in ESI † Fig. S9.…”

Controlled growth of a graphdiyne-Prussian blue analog heterostructure for efficient ammonia production

“…Compared with traditional carbon materials, GDY has an unparalleled advantage in that it can be grown controllably on the surface of any substrate under low temperatures and mild conditions. Benefiting from these unique properties, a number of GDY-based materials have been fabricated and have shown potential in various fields, including catalysis, energy conversion and storage, batteries, solar cells, intelligence, and life sciences 5,9,[46][47][48][49][50][51][52][53][54][55][56][57][58][59][60][61] . These advantages of GDY make it an ideal material for constructing of interface structures with a significant numbers of active sites, facilitated charge transfer, enhanced catalytic activity and longterm stability.…”