Precise synthesis of N-doped graphitic carbon via chemical vapor deposition to unravel the dopant functions on potassium storage toward practical K-ion batteries

Abstract

Nitrogen doped carbon is a burgeoning anode candidate for potassium-ion battery (PIBs) owing to its outstanding attributes. It is imperative to grasp further insight into specific effects of different nitrogen dopants in carbon anode toward advanced K-ion storage. However, the prevailing fabrication method is plagued by the fact that considerable variations in the total N-doping concentration occur in the course of regulating the type of nitrogen dopants, incapable of distinguishing the certain roles of them under similar conditions. Herein, throughout the precise preparation of high edge-N doped carbon (HENC) and high graphitic-N doped carbon (HGNC) harnessing basically identical N-doping levels (5.78 at.% for HENC; 5.07 at.% for HGNC) via chemical vapor deposition route, the effects of edge-N and graphitic-N in the carbon anode on K-ion storage are revisited, offering guidance into the design of low-cost and high-performance PIB systems.

High Capacity and Fast Kinetics of Potassium-Ion Batteries Boosted by Nitrogen-Doped Mesoporous Carbon Spheres

“…Besides, some evident peaks aligned with the position of KHCO 3 (PDF No. 70-1168), which may be derived from the irreversible side reaction; especially, the peak near to 23° may correspond to the residual electrolyte KPF 6 [ 51 ].…”

P/N Co‐doped Carbon Nanotubes with Dominated Capacity‐controlled Absorption Effect Enabling Superior Potassium Storage

“…The reason was that P had a lower electronegativity than N, which could act as a stronger electron donor to change the electron density of PNCNTs [19c] . Three typical nitrogen peaks, corresponding to pyridinic‐N (N‐6, 398.2 eV), pyrrolic‐N (N‐5, 400.5 eV), and graphite‐N (N−Q, 403 eV) were observed for both samples (Figure 2(e) and Figure S5) [17b,19c,28] . Correspondingly, the peak position of the N 1s spectra shifted to a higher binding energy from 399.32 to 400.38 eV after the incorporation of P into the carbon nanotubes [15] .…”

“…This is mainly because these substituted heteroatoms (such as N ,[8b,11a,11d,12] S, [13] B, [11c] O, [9,14] P, [11e,15] and F [11b,16] ) generally can optimize the electronic conductivity of the material, modify its electronic structure, provide more electrochemically active sites and expand interlayer spacing [10,17] . In the research of heteroatom‐doped carbon‐based anode materials for PIBs, the most is to introduce more defects and active sites into the carbon skeleton through N‐doping to improve the electronic conductivity of the material, provide potassium ion storage and faster reaction kinetics [12,17b,18] . In addition, P doping is also a good choice, which can exhibit stronger electron donating ability and expand the interlayer spacing of the graphitic layer due to P's lower electronegativity and larger radius than nitrogen [7,19] .…”

Harmonized edge/graphitic‐nitrogen doped carbon nanopolyhedron@nanosheet composite via salt‐confined strategy for advanced K‐ion hybrid capacitors

“…In fact, the balance/contribution from graphitic‐nitrogen (N‐Q) species has been normally overlooked in the realm of potassium storage. Since nitrogen is more electronegative than carbon, the incorporation of N‐Q not only sustains the electrical conductivity of the material but also improves the system stability toward potassium storage 55,56 . More significantly, the higher charging capacity delivered by NC‐800 in the low voltage range as compared to NC‐700 and NC‐900 renders it even more suitable for practical anodes in full‐cell applications.…”