Structure‐Engineered Low‐Cost Carbon Microbelt Hosts for Highly Robust Potassium Metal Anode

Abstract

Potassium metal as anode is an ideal material for the assembly of high specific energy batteries. However, safety issues caused by unrestricted dendrite growth and “dead K” generation severely limit their application. Here, based on the concept of waste recycling, a structural engineering strategy (chemical exfoliation and enzyme‐assisted synergistic method) is proposed to prepare oxygen‐containing functionalized porous carbon microbelts (OPCMs) as freestanding K metal hosts. The porous structure, uniformly distribution of carbon nanospheres, and the presence of oxygen‐containing functional groups reduce the energy barrier of K nucleation and promote the deposition kinetics. Benefitting from these advantages of OPCMs, the OPCMs‐based K composite anodes (K‐OPCMs) are free of obvious dendrite growth during the plating process. Symmetric cells assembled with K‐OPCMs maintain a stable overpotential of 40 mV after cycling for more than 800 h at 1 mA cm−2. In addition, the K‐OPCMs//organic cathode (PTCDA) full cell exhibits excellent rate capability (96% capacity retention, 100–2000 mA g−1, which is superior to most reported potassium metal batteries) and ultralong lifespan (97.8 mA h g−1, after 1500 cycles at 2000 mA g−1). This study illustrates the effectiveness of structure‐engineered and provides a guiding insight for achieving high‐performance rechargeable batteries.

Hydroxyl‐Decorated Carbon Cloth with High Potassium Affinity Enables Stable Potassium Metal Anodes

“…Specifically, based on the high‐resolution C 1s XPS spectra, the peaks observed at 288.8, 285.6, and 284.5 V correspond to the C═O, C─O/C─N, and C─C/C═C bonds, respectively (Figure 2c). [ 34 ] The peaks located at ≈285.6 eV indicate the C─O content decreases and the C─N content increases from EG‐CC to EDA‐CC.…”

Synergy of Cu-foam/Sb2O3/rGO for stable potassium anodes of high-rate and low-temperature potassium metal batteries

“…The electrode potential of the K/K + redox couple is similar to that of Li/Li + (= −2.93 V vs. SHE), making it suitable for KIB applications in terms of cell voltage and energy density. 13,14 Furthermore, the K metal anode electrode exhibits a high theoretical specific capacity of 687 mA h g −1 and possesses a redox potential close to that of Li/Li + (−3.04 V vs. SHE). When combined with the cathode electrode, it enables the attainment of elevated battery voltage and energy density.…”

3D Micro‐Flower Structured BiFeO3 Constructing High Energy Efficiency/Stability Potassium Ion Batteries Over Wide Temperature Range

“…[7][8][9][10] It has become essential and pressing to explore advanced metalion batteries as an alternative. [11][12][13][14] Potassium-ion batteries (PIBs) have captured worldwide research interests due to their lithium-like electrochemical properties, abundant reserves, and relatively moderate cost. [15][16][17][18] Furthermore, K + has a lower Lewis acidity compared with Li + and Na + , demonstrating superior desolvation capability and faster ion diffusion kinetics in the electrolyte.…”