g-C3N4/NaNbO3复合材料降解混合染料的热释电光催化性能  

Pyrophotocatalytic Performance of g-C_(3)N_(4)/NaNbO_(3) Composite Material for Degradation of Mixed Dyes

作　　者：徐利[1] 邓树文 周小桔 王会峰 胡正龙 XU Li;DENG Shuwen;ZHOU Xiaoju;WANG Huifeng;HU Zhenglong(School of Mathematics,Physics and Optoelectronic Engineering,Hubei University of Automotive Technology,Shiyan 442002,Hubei,China;Hubei Engineering Research Center for Big Data Application of Intelligent Emergency Services,Xianning 437100,Hubei,China;School of electronic and Information Engineering,Hubei University of Science and Technology,Xianning 437100,Hubei,China)

机构地区：[1]湖北汽车工业学院,数理与光电工程学院,湖北十堰442002 [2]湖北科技学院,智能应急服务大数据应用湖北省工程研究中心,湖北咸宁437100 [3]湖北科技学院,电子与信息工程学院,湖北咸宁437100

出　　处：《硅酸盐学报》2025年第3期594-606,共13页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(12304539);湖北科技学院博士科研启动基金(BK202316);湖北科技学院科研项目(2020-22GP08,2024-2025X08)。

摘　　要：热释电效应诱导的热释电势已被证明是抑制载流子复合和促进电荷输运的有效策略之一。采用水热和烧结两步法制备了g-C_(3)N_(4)/NaNbO_(3)纳米棒复合材料。通过光照加冷热循环降解混合染料(酸性橙AO7、罗丹明Rh B、甲基橙MO和亚甲基蓝MB),复合材料展现了优异的热释电光催化性能。结果表明,无需外部热源,经90 min 10次冷热循环,g-C_(3)N_(4)/NaNbO_(3)对混合染料的热释电光催化降解率达到96.9%,反应速率为0.0386/min。此外,通过不同混合染料浓度、不同pH值、不同水源及5次重复使用的实验表明,复合催化剂具有强的环境适应性和稳定性。自由基探测实验表明,·O_(2)^(-)、·OH和h+是反应中的活性物质,以·O_(2)^(-)和·OH为主。根据捕获实验、Mott-Schottky曲线、密度泛函理论(DFT)计算表明,g-C_(3)N_(4)/NaNbO_(3)增强的热释电光催化活性归因于S型异质结的形成、g-C_(3)N_(4)和Na Nb O_(3)之间的内建电场,以及热释电势导致的能带弯曲,加速了光生载流子的空间分离和迁移。这项工作表明g-C_(3)N_(4)/NaNbO_(3)复合材料是一种有前景的环保型热释电光催化剂,可以通过收集太阳能和昼夜温差热能来净化复杂的废水。Introduction With the rapid development of industry,the discharge of dye wastewater from the textile and printing industries poses a huge threat to aquatic ecosystems and human health.Exploring efficient catalytic technologies to reduce water pollution is highly anticipated.Photocatalysis,as an efficient and environmentally friendly advanced oxidation technology for decomposing organic dyes,has attracted considerable attention.However,the low utilization rate of solar energy and severe photogenerated carrier recombination restrict the practical application of photocatalysis.In addition to solar energy,the thermal energy generated by cold-hot alternation can be also used as a clean and renewable energy source to induce positive and negative charges and generate pyroelectric potential,thereby achieving pyrocatalysis.Combining pyrocatalysis with photocatalysis can simultaneously collect solar energy and alternating heat energy,and the pyroelectric potential can serve as an internal driving force for dissociating photo generated exciton.This work constructed g-C_(3)N_(4)/NaNbO_(3)composite materials for the absorption of g-C_(3)N_(4)to visible light to enhance the utilization efficiency of sunlight.The Mott-Schottky curve was obtained by electrochemical workstation to analyze the conduction type and flat band potential of g-C_(3)N_(4)and NaNbO.Methods A hydrated NaNbO_(3)sample was obtained via hydrothermal reaction at 160℃for 4 h with Nb2O5 and NaOH as raw materials.The hydrated NaNbO_(3)prepared was then mixed,ground with a certain mass of melamine powder(in a mass ratio of 1:2),and sintered at 500℃for 2 h to obtain g-C_(3)N_(4)/NaNbO_(3)composite material.The phase,morphology,and optical properties of the product was analyzed by X-ray diffraction(XRD),scanning electron microscopy(SEM),and ultraviolet-visible spectroscopy(UV-Vis).The pyrophotocatalytic performance of g-C_(3)N_(4)/NaNbO_(3)composite materials was evaluated via degrading mixed dyes(i.e.,methylene blue MB,methyl orange MO,rhodamine RhB,and acid or

关 键 词：石墨相氮化碳/铌酸钠 热释电光催化 热释电势 复合材料 内建电场 

分 类 号：O649.4[理学—物理化学] TB332[理学—化学]