Introduction Increasing the energy density of lithium-ion batteries (LIBs) is an important issue in energy research in order to meet growing energy demands and long-term sustainability. These findings therefore provide new insights into the mechanistic models of doped graphene as LIB anodes, which are important in improving the anode designs for better LIB performance. In addition, post-mortem XPS measurements of nitrogen-doped graphene cycled as a lithium-ion battery anode are conducted for the first time, which reveal direct evidence for irreversible chemical changes at the nitrogen sites during cycling. As an anode material we find that pyridinic-type N-GNSPs perform similarly to undoped GNSPs, suggesting that pyridinic sites alone are not responsible for the enhanced performance of nitrogen-doped graphene observed in previous studies, which contradicts common conjectures. The as-grown N-GNSPs are compared with undoped GNSPs using scanning electron microscopy (SEM), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), helium ion-beam microscopy (HIM), and electrochemical methods. Liquid nitrogen is a common cryogen, used in the preservation of bodies and reproductive cells and for the storage of biological samples.We report a high-yield single-step method for synthesizing nitrogen-doped graphene nanostripes (N-GNSPs) with an unprecedentedly high percentage of pyridinic-type doping (>86% of the nitrogen sites), and investigate the performance of the resulting N-GNSPs as a lithium-ion battery (LIB) anode material.
Nitrogen also provides an inert atmosphere in tanks containing explosive liquids. The largest commercial use of nitrogen is in the form of ammonia. Found abundantly, nitrogen constitutes 78% of Earth’s atmosphere. Normally a gas, nitrogen is colorless, odorless, and tasteless. The mixture of nitric and hydrochloric acids is able to dissolve gold. However, compounds of nitrogen were recognized in the Middle Ages. It was discovered by Daniel Rutherford in 1772. 79, 5174 (1997).Īs a crucial part of amino and nucleic acids, nitrogen is vital to all forms of life. Nitrogen-containing aromatic polymers (e.g., polyimide) may have weak π-π* satellite features shifted several eV from the main nitrogen peak.Angle resolved XPS is the appropriate method for identifying the depth distributions of.Sputter profiling cannot be used to depth profile these states.These states decay rapidly with Ar+ sputtering, even at low beam energies.Thermodynamically unstable (and are typically not observed for annealed silicon Higher binding energy states (with oxygen atoms substituted in place of silicon) are.A variety of nitrogen bonding states may be observed in as received silicon oxynitride samples.During sputter profiling, if nitrogen is observed when it should not be present, this probably indicates a leak to air in the argon supply.Acquire the N1s / Hf4p 3/2 region and the associated hafnium plasmon (365–410eV).When analyzing nitrogen-containing hafnium compounds (e.g., nitrided hafnium silicate), the plasmon loss feature from the Hf4p 3/2 feature badly overlaps the N1s region.
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