Lithium Ion Regulates Two-dimensional Material And Its Application In Oxygen Evolution Reaction

Currently,as a renewable clean energy,hydrogen is the most promising candidate to replace fossil fuels and other non-renewable resources.Presently,water splitting to produce hydrogen is one of the most popular hydrogen production methods.Oxygen evolution reaction is the anodic reaction of water splitting reaction.Because of its kinetic sluggish,it becomes the main speed limiting step of water splitting.Noble metals have standout catalytic properties for OER.However,limited by the high price and resources,precious metals are limited to widely used in industry.Now the main researches focus on how to prepare non-precious metal catalysts with more abundant resources.The main contents of this paper are as follows:?1?As a common cathode material for lithium ion batteries,lithium cobalt oxide is widely used in portable electronic devices such as mobile phones and notebooks.However,spent lithium cobalt recovery is indeed a major problem now,because lithium cobalt oxide may cause pollution to the environment.Most of the current recycling methods need harsh conditions,which will cause two wastes of energy and potential safety problems.In this work,the results of SEM and HRTEM tests showed that the reasons for the failure of lithium cobaltate include volume expansion and lattice fault,and the XPS test also found that the electron state around the cobalt and oxygen atoms on the surface of lithium cobalt acid has greatly changed.We test the oxygen precipitation of lithium cobalt recovered after re cycling.It has found that in alkaline solution,its performance is obviously better than that of the original lithium cobalt lithium,and it is found that with the increase of lithium ion cycle number,the performance of OER is increasing,which provides a new idea for the recovery and reuse of positive materials,and this direct reutilization.The method is safe and will not cause two energy waste and pollution.Using the working principle of lithium ion battery to modification the electrocatalytic performance of CoFe LDH,it is found that the CO₃^2-irreversible combination of lithium ion and CoFe LDH layer during the cycle of lithium ion battery is converted to CoFe alloy and lithium carbonate,and the size of the alloy particles decreases with the increase of the lithium ion cycle,by XRD test.It also dispersed uniformly on the Super P substrate,which improved the agglomeration and instability of the alloy nanoparticles,and showed excellent OER performance.However,when the cycle number is higher than 10 cycles,the OER performance begins to decay.It may be due to the SEI film formed on the surface,which leads to the decrease of the surface electron transfer rate,which leads to the degradation of the catalytic performance.By using the principle of lithium ion battery to control two-dimensional material and then improve its catalytic performance,the method is simple and easy to operate and implement,is an effective and convenient method of two-dimensional material regulation.