Application Of Copper/Carbon Composite Nanomaterials In Medical Catalysis And Energy Catalysis

Cancer is the "number one killer" affecting human health,and exploring durable and effective treatment methods has become an important research direction in the medical field.The current mainstream treatments for cancer include surgery,chemotherapy and radiotherapy,but these traditional treatments all have inherent defects in their therapeutic effects.Nanocatalytic therapy,as an emerging therapeutic method,is attracting widespread attention to precisely kill tumors without damaging normal tissues and organs.Cuprous-based nanocatalytic materials can promote the generation of hydroxyl radicals(·OH)and inhibit the overexpression of glutathione(GSH)in the tumor microenvironment(TME),and improve the effect of chemodynamic therapy(CDT),so prepared a cuprous-based nanocatalyst with good performance is expected to achieve breakthroughs in cancer treatment and actively promote the application of nanocatalytic therapy in the medical field.In the face of increasingly severe "greenhouse effect" and energy shortage,electrocatalytic carbon dioxide reduction reaction(CO2RR)can not only use renewable electric energy to consume carbon dioxide,but also convert carbon dioxide into high value-added chemical energy,which has become a research direction of great concern.Among all electrocatalysts,copper-based nano catalyst is the only catalyst that can prepare alcohols and hydrocarbons in electrocatalytic CO2RR.Therefore,the preparation of high-performance copper-based nano catalysts by various means has important practical value.In this thesis,copper-based materials are used as the starting point to prepare highperformance copper-based catalysts by adopting different design schemes and control methods,so that they can be efficiently used in cancer treatment and electrocatalytic CO2RR,and continuously improve the application value of copper-based materials.The main content of this paper is divided into the following three aspects:(1)Although cuprous nanocatalyst can efficiently catalyze the occurrence of Fenton-like reaction and inhibit GSH overexpression in TME,resulting in tumor-killing effects,but there are still some problems such as extremely unstable Cu+,easy oxidation and poor biocompatibility.To this end,in this chapter,we successfully prepared nitrogen-doped carbon-coated hollow cuprous oxide nano-catalyst(HCONC)by solvothermal method and changing the experimental conditions,which was used to catalyze the cascade reaction and improve the CDT effect.The Cu+ released by HCONC in TME can effectively decompose H2O2 to generate ·OH through Fenton-like reaction,and consume the overexpressed GSH,which has a good inhibitory effect on tumors.The surface carbon layer of HCONC can effectively prevent the oxidation of Cu+,improve the stability of Cu2O nanocrystals,make it have good biocompatibility,and show a good application prospect of tumor CDT.(2)Copper-based nanocatalysts can effectively prepare liquid products such as alcohols in electrocatalytic CO2RR,but it is difficult for the same catalyst to achieve efficient selection for different liquid-phase products at different potentials.The ultrasmall Cu nanocrystal-embedded nitrogen-doped carbon nanosheet catalysts(Cu/NCNSs)prepared in this chapter can achieve efficient selection of ideal products at different potentials.At-0.37 V and-0.77 V(Reversible Hydrogen Electrode potential),the faradaic efficiency(FE)of C2H5OH and HCOOH reached 43.7%and 63.5%,respectively.In addition,the Cu/NC-NSs exhibited good catalytic stability,and the catalytic performance did not deteriorate significantly after 16 h of smooth operation.Through density functional theory(DFT)calculations,the active sites of Cu/NC-NSs in electrocatalytic CO2RR were clarified.Meanwhile,nitrogen-doped carbon nanosheets(NC-NSs)form an excellent synergy with ultra-small copper atoms in electrocatalytic CO2RR,which can effectively tune the electronic structure of copper atoms to promote proton-electron transfer,thereby exhibiting excellent catalytic selectivity in CO2RR.This work provides a reference for the preparation of copperbased nanocatalysts with good selectivity for electrocatalytic CO2RR.(3)Although copper-based nanocatalysts have made great progress in the electrocatalytic CO2RR to C2 products,there is still a big gap in the preparation of C3 products,especially n-propanol.As an important scientific research means,high magnetic field can be used to control the preparation process of materials and improve the properties of materials.In this chapter,we prepared high-performance carbon-doped copper-oxygen catalysts(Cu/O-9T)by solvothermal method under a high magnetic field(9T).The Cu/O-9T was used in electrocatalytic CO2RR,the FE of n-propanol was increased to 18.23%with a partial current density of 18.19 mA·cm-2 at a potential of 0.57 V,reaching the highest level of FE that has been reported so far to generate npropanol in electrocatalytic CO2RR.In addition,the Cu/O-9T exhibited ultra-high stability,and the catalytic performance did not deteriorate significantly during the operation of up to 45 h.This work provides a strong reference for the high magnetic field as an important regulation means in the process of material preparation for improving the electrocatalytic CO2RR performance.Meanwhile,it provides a new perspective and approach for the preparation of efficient electrocatalytic material system in the future.