为了制备室温下对NOx吸附性能优异的纳米材料,采用表面活性剂辅助的纳米粒子自组装方法制备了纳米多级结构扁圆型多孔α-Fe2O3。分别采用XRD、FT-IR、TG-DSC、SEM及TEM等技术手段研究了材料的形貌与结构。研究表明,每一个扁圆型的Fe2O3是由8～10nm左右的Fe2O3纳米颗粒聚集而成,属赤铁矿型的α-Fe2O3,晶型较好。在室温下对材料进行NOx的吸附脱附实验,研究发现,该材料的选择性吸附NOx能力和吸附量较市售的α-Fe2O3明显提高。原因在于,空气中的氧气吸附于多孔α-Fe2O3材料表面,形成的氧负离子,与NOx形成化学吸附,有助于提高NOx的吸附性能。初步探讨NOx的吸附机理,为半导体氧化物在室温下NOx检测提供了重要实验基础。%To synthesize nanomaterial with good NOx adsorption ability at room temperature, a porous oblate- Like α-Fe2O3 has been synthesized by the technology of surfactant-assisted nanoparticles assembly and its NOx adsorption behavior at room temperature was studied. The means of XRD, FT-IR, TG-DSC, SEM and TEM were used to investigate the morphology and structure. The result show that every oblate-like Fe2O3 consist of nanoparticles with diameter of 8-10nm assembly, and it belongs to hematite phase of α-Fe203 with better crys- tal. The room temperature NOx, adsorption-desorption experiments reveals that the selective NOx adsorption a- bility of the synthesized material was obviously improved compared with purchase α-Fe203. The reason was that O2 in the air was adsorbed on the surface of the oblate-like α-Fe2O3, then O- was formed which can chemi- cal adsorb with NOx molecular. The formation mechanism of NOx adsorption was preliminarily discussed and important experiment basis were introduced for semiconductor oxide at room temperature NOx detection.
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