【摘要】 采用介质阻挡放电等离子体法合成了氧原子掺杂的具有氮空穴的石墨相氮化碳催化剂（g-C₃N₄）,并对催化剂的结构和形貌进行了表征分析.结果表明,等离子体处理没有改变催化剂的形貌,并同时将氮空穴和氧原子引入了g-C₃N₄的晶格.在可见光条件下,制备的共掺杂g-C₃N₄催化剂的铵离子产率高达5. 9 mg·L^-1·h^-1·g_cat^-1,分别是具有氮空穴的g-C₃N₄和纯g-C₃N₄的2. 2倍和20倍,同时还表现出优异的催化稳定性.密度泛函理论计算结果显示,与具有氮空穴的g-C₃N₄相比,氧原子的引入能提高氮空穴对反应物氮气分子的活化能力,提高光催化固氮性能.更多还原

【Abstract】 N vacancy and oxygen co-doped g-C₃N₄ with outstanding N₂ photofixation ability was synthesized by dielectric barrier discharge plasma treatment. XRD,UV-Vis,N₂ adsorption,SEM,XPS,PL and TPD were used to characterize the as-prepared catalysts. The result shows that plasma treatment does not change the morphology of as-prepared catalyst but introduce nitrogen vacancies and oxygen into g-C₃N₄ lattice simultaneously. The as-prepared co-doped g-C₃N₄ displays the ammonium ion production rate as high as 5. 9 mg·L^-1·h^-1·g_cat^-1 ,which is 2. 2 and 20 times that of individual N vacancy-doped g-C₃N₄ and neat g-C₃N₄,as well as good catalytic stability. Experimental and density functional theory（ DFT） calculation results indicate that,compared with individual N vacancies doping,the introduction of oxygen can promote the activation ability of N vacancies to N₂ molecule,leading to the promoted N₂ photofixation performance.更多还原