Synthesis And Photothermal Properties Of Titanium Nitride Based Nanomaterials

In recent years,photothermal anti-tumor therapy and solar water evaporation have become the hot research topic.As a result,many new types of photothermal conversion materials have been successfully prepared,but most of the prepared photothermal conversion materials are suffering from many shortcomings,such as poor photothermal stability,low photohthermal conversion capability and questionable biocompatibility,considering their complexity of production,high cost and low yield,it is still a huge challenge to put these photothermal conversion materials into practical application.Therefore,the design and fabrication of multi-functional photothermal conversion materials with excellent light absorption,high efficiency phtothermal conversion performance,high photothermal stability and good biocompatibility for photothermal anti-tumor therapy and solar water evaporation have become especially important.Herein,titanium nitride nanoparticles?TiN NPs?are synthesized by a sol-gel reduction nitridation synthesis method and then surface-modified with polyacrylic acid?PAA?to improve the stability in the physiological solution.Finally,the multi-functional photothermal conversion materials?TiN-PAA NPs?with solar water evaporation performance and phtothermal therapy performance are successfully synthesized.The finally synthesized TiN-PAA NPs are revealed to present high stability in the stability test.The result of the photothermal performance test shows that TiN-PAA NPs present strong near-infrared light absorption and have the ultrahigh photothermal conversion efficiency of 41.1%under 808 nm laser irradiation.Moreover,in the performance test of solar water evaporation,the TiN-PAA NPs exhibit 95%light absorption under simulated sunlight,resulting in rapidly generated water vapor at a rate of 1.52 kg·m^-2·h^-1,and high photothermal evaporation water efficiency of 95%.After 30hours of irradiation,the TiN-PAA NPs can still generate water vapor at an average rate of 1.44 kg·m^-2·h^-1,showing good cycle stability.In addition,in a series of in vitro cell experiments,the TiN-PAA NPs show extemely low cytotoxicity,indicating its good biocompatibility.Under the near-infrared laser irradiation,the TiN-PAA NPs can not only realize more than 80%photothermal killing to cancer cells but also exhibit high contrast infrared thermal imaging capacity,implying that the TiN-PAA NPs have promising application potential in the field of medical diagnosis and treatment.In conclusion,the TiN-PAA NPs prepared by the simple method in this thesis can be used as a novel photothermal conversion material in the applications of solar water evaporation and photothermal anti-tumor therapy.This multifunctional nanomaterial with excellent photothermal therapy performance and solar water evaporation performance may have opened up a feasible route to design and develope novel photothermal conversion materials.