以混合金属草酸盐为前驱体,通过焙烧、空气气氛露置等处理,制备了多价态Ag-ZnO复合多孔光催化材料.以甲基橙溶液为降解对象,考察了复合光催化剂在紫外光作用下的光催化性能并对其机理进行了探讨.结果表明Ag-ZnO光催化活性与焙烧温度、升温速率、焙烧时间等因素有关.较慢的升温速率和焙烧时间的延长均有利于催化活性的提高.焙烧温度高则不利于高催化活性催化剂的制备.催化剂光催化活性随露置天数的增加先增大后减小,与复合物中纳米银在空气气氛下的物相变化有关.以5 ℃/min的升温速率将前驱体加热至450 ℃并维持6 h,产物于空气气氛下露置6 d,所得催化剂催化活性最高.
Porous Ag-ZnO catalyst was synthesized by calcining the mixed metal oxalate precursor and subsequent exposure in air. The photocatalytic activity under ultraviolet light was evaluated by photocatalytic degradation of methyl orange.The reaction mechanism was also studied. The experimental results show that the photocatalytic activity was influenced by the calcination temperature, calcination period and the heating-up rate. The slower heating-up rate and the longer calcination period were favor of the improvement of photocatalytic activity, while the photocatalytic activity decreases with the higher calcination temperature. The difference of photocatalytic activity for the complex catalysts with exposed period was related to the variation of Ag phase in air. The optimum catalyst was obtained by calcining the precursor doped 4% Ag at 450 ℃ for 6 h at the heating-up rate of 5 ℃/min and subsequent exposure treatment for 6 d in air.
参考文献
| [1] | Miyauchi M.;Nakajima A.;Watanabe T.;Hashimoto K. .Photocatalysis and photoinduced hydrophilicity of various metal oxide thin films[J].Chemistry of Materials,2002(6):2812-2816. |
| [2] | 张靖峰,杜志平,赵永红,台秀梅.纳米Ag/ZnO光催化剂及其催化降解壬基酚聚氧乙烯醚性能[J].催化学报,2007(05):457-462. |
| [3] | Ming Jin;Xintong Zhang;Shunsuke Nishimoto;Zhaoyue Liu;Donald A. Tryk;Alexei V. Emeline;Taketoshi Murakami;Akira Fujishima .Light-Stimulated Composition Conversion in TiO2-Based Nanofibers[J].The journal of physical chemistry, C. Nanomaterials and interfaces,2007(2):658-665. |
| [4] | Zhou G;Deng HC .Preparation and photocatalytic performance of Ag/ZnO nano-composites[J].Materials science in semiconductor processing,2007(2/3):90-96. |
| [5] | Awazu K;Fujimaki M;Rockstuhl C;Tominaga J;Murakami H;Ohki Y;Yoshida N;Watanabe T .A plasmonic photocatalyst consisting of sliver nanoparticles embedded in titanium dioxide[J].Journal of the American Chemical Society,2008(5):1676-1680. |
| [6] | Konta R;Ishii T;Kato H K et al.Photocatalytic activities of noble metal ion doped SrTiO_3 under visible light irradiation[J].Journal of Physical Chemistry B,2004,108(26):8992-8995. |
| [7] | Weiwei Lu;Shuyan Gao;Jianji Wang .One-Pot Synthesis of Ag/ZnO Self-Assembled 3D Hollow Microspheres with Enhanced Photocatalytic Performance[J].The journal of physical chemistry, C. Nanomaterials and interfaces,2008(43):16792-16800. |
| [8] | Height MJ;Pratsinis SE;Mekasuwandumrong O;Praserthdam P .Ag-ZnO catalysts for UV-photodegradation of methylene blue[J].Applied Catalysis, B. Environmental: An International Journal Devoted to Catalytic Science and Its Applications,2006(3/4):305-312. |
| [9] | Yuanhui Zheng;Lirong Zheng;Yingying Zhan .Ag/ZnO Heterostructure Nanocrystals:Synthesis,Characterization,and Photocatalysis[J].Inorganic Chemistry: A Research Journal that Includes Bioinorganic, Catalytic, Organometallic, Solid-State, and Synthetic Chemistry and Reaction Dynamics,2007(17):6980-6986. |
| [10] | Zhang YY;Mu J .One-pot synthesis, photoluminescence, and photocatalysis of Ag/ZnO composites[J].Journal of Colloid and Interface Science,2007(2):478-484. |
| [11] | 贾志刚,岳林海,郑遗凡,徐铸德.纳米晶构筑一维多孔氧化锌的合成与表征[J].无机化学学报,2007(07):1277-1281. |
| [12] | 魏剑英,韩周祥,赵玛,王军,彭辉,胡季帆.Ag2C2O4热分解法制备纳米银粉[J].稀有金属材料与工程,2007(11):2049-2051. |
| [13] | Reenamole Georgekutty;Michael K. Seery;Suresh C. Pillai .A Highly Efficient Ag-ZnO Photocatalyst: Synthesis, Properties, and Mechanism[J].The journal of physical chemistry, C. Nanomaterials and interfaces,2008(35):13563-13570. |
| [14] | Ohtani B;Ogawa Y;Nishimoto S I .Photocatalytic activity of amorphousanatase mixture of titanium(IV) oxide particles suspended in aqueous solutions[J].Journal of Physical Chemistry B,1997,101:3746-3752. |
| [15] | 洪中山,曹勇,孙琦,邓景发,范康年.焙烧条件对Cu/ZnO/Al2O3甲醇催化剂的影响[J].复旦学报(自然科学版),2002(03):330-334. |
| [16] | 杨晓东,赵青南,韩宾,赵修建.银纳米薄膜在室温大气条件下的氧化机理[J].硅酸盐学报,2008(07):954-959. |
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