Modification of TiO(2) by Bimetallic Au-Cu Nanoparticles for Wastewater Treatment.
Modification of TiO(2) by Bimetallic Au-Cu Nanoparticles for Wastewater Treatment.
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DOI：
10.1039/c3ta11684k
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发表时间：
2013-09-28
期刊：
影响因子：
--
通讯作者：
Remita H
中科院分区：
文献类型：
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作者：
Hai Z;Kolli NE;Uribe DB;Beaunier P;José-Yacaman M;Vigneron J;Etcheberry A;Sorgues S;Colbeau-Justin C;Chen J;Remita H
通过用四羟甲基氯化膦（THPC）（0.5wt%）还原金属前体，在商业TiO 2化合物（P25）表面上合成了Au、Cu和Cu-Au-Cu纳米颗粒。通过HAADF-STEM、EDS、HRTEM和XPS等测试手段对纳米颗粒的合金化结构进行了表征。研究了改性后的TiO 2在紫外-可见光照射下对悬浮液中苯酚的光催化降解性能。通过金属纳米颗粒的改性诱导光催化活性的增加。当Au-Cu/TiO_2（Au/Cu = 1：3）时，光催化活性最高。用时间分辨微波电导法（TRMC）研究了它们的电子性质。TRMC测量表明，与Au，Cu和Au-Cu纳米粒子的TiO 2改性起着电荷载流子分离的作用，增加在紫外光下的活性。实际上，金属纳米颗粒充当电子的吸收器，减少电荷载流子复合。TRMC测量还表明，纳米金铜比单金属Au和Cu的更有效的电子清除。
Au, Cu and bimetallic Au-Cu nanoparticles were synthesized on the surface of commercial TiO2 compounds (P25) by reduction of the metal precursors with tetrakis (hydroxymethyl) phosphonium chloride (THPC) (0.5 % in weight). The alloyed structure of Au-Cu NPs was confirmed by HAADF-STEM, EDS, HRTEM and XPS techniques. The photocatalytic properties of the modified TiO2 have been studied for phenol photodegradation in aqueous suspensions under UV-visible irradiation. The modification by the metal nanoparticles induces an increase in the photocatalytic activity. The highest photocatalytic activity is obtained with Au-Cu/TiO2 (Au/Cu 1:3). Their electronic properties have been studied by time resolved microwave conductivity (TRMC) to follow the charge-carrier dynamics. TRMC measurements show that the TiO2 modification with Au, Cu and Au-Cu nanoparticles plays a role in charge-carrier separations increasing the activity under UV-light. Indeed, the metal nanoparticles act as a sink for electron, decreasing the charge carrier recombination. The TRMC measurements show also that the bimetallic Au-Cu nanoparticles are more efficient in electron scavenging than the monometallic Au and Cu ones.