化工新型材料

化工新型材料 ›› 2020, Vol. 48 ›› Issue (11) : 203-208. DOI: 10.19817/j.cnki.issn 1006-3536.2020.11.045

科学研究

纳米硅和纳米银复合颗粒对二氧化钛可见光光催化性能的影响

作者信息 +

Influence of nano-silica-silver composite particle on TiO₂ visible light photocatalytic activity

Author information +

文章历史 +

PDF

摘要

以TiO₂为基体,通过水相共沉淀法掺入纳米硅、纳米银颗粒,制备了Si/TiO₂和Ag@Si/TiO₂复合催化剂。利用X射线衍射仪、扫描电子显微镜、紫外-可见分光光度计、电化学工作站、光致发光光谱仪对样品的晶体结构、微观形貌、光吸收性能、阻抗特性及电子空穴复合速率等进行表征,研究复合体系中Si掺杂量对可见光催化降解罗丹明(RhB)和亚甲基蓝(MB)染料的影响。结果表明:含Si的复合体系其可见光吸收光谱发生明显红移,且在长波长范围出现吸收峰。Si掺杂量为1%(质量分数)时,复合催化剂光吸收强度最强,催化效率最快。纳米银颗粒的引入进一步提高了Si/TiO₂的可见光催化性能。可见光照射2.5h后,Ag@Si/TiO₂对RhB的降解率比TiO₂提高了14%;可见光照射3.5h后,Ag@Si/TiO₂对RhB的降解率达到99%。在TiO₂中掺入纳米硅和纳米银颗粒,银硅复合物Ag@Si一方面提供更多的光生电子-空穴对;另一方面充当电子受体,载流子迁移率得到提高,抑制了TiO₂半导体光生电子与空穴的复合,从而提高了对RhB、MB的降解率。

Abstract

Based on titanium dioxide(TiO₂),Si/TiO₂ and Ag@Si/TiO₂ composites were prepared by incorporation of nano-silicon (Si) and silver (Ag) particles by aqueous phase coprecipitation method.X-ray diffraction(XRD),scanning electron microscopy(SEM),UV-Visible spectrum,electrochemical impedance spectroscopy(EIS) and photoluminescence spectroscopy(PL) etc.were used to characterize the crystal structure,morphology,optical properties,impedance characteristics and electron hole recombination rate of samples,to find out the effect of the doping amount of elemental composition of Si on the photocatalytic degradation of Rhodamine dye (RhB) and methylene blue (MB) by visible light.Results shown that the visible light absorption spectrum of the composite system containing Si was obviously red-shifted,and the absorption peak appeared in the long wavelength range.When the Si doping amount was 1wt%,the composite catalytic material had the strongest light absorption intensity and the fastest catalytic efficiency.Compared with pure TiO₂ particles,the photocatalytic performance of Ag@Si/TiO₂ was obviously improved.Under the condition of visible light excitation and degradation for 3.5h,the degradation rate of RhB by Ag@Si/TiO₂ was 99%,and under 2.5h conditions,compared with TiO₂,the degradation rate reached 14%.On the one hand incorporating Si and Ag into TiO₂ nanoparticles,Ag@Si provided more photogenerated electron-hole pairs.On the other hand,Ag acted as an electron acceptor,carrier mobility was improved,and TiO₂ semiconductor photogenerated electrons and holes recombination were suppressed,enhanced the degradation efficiency of RhB and MB.

关键词

可见光催化 / 纳米硅 / 二氧化钛 / 纳米银颗粒

Key words

visible photocatalysis / nanosilicon / titanium dioxide / silver nanoparticle

引用本文

引用格式 ▾

纳米硅和纳米银复合颗粒对二氧化钛可见光光催化性能的影响[J]. 化工新型材料, 2020, 48(11): 203-208 DOI:10.19817/j.cnki.issn 1006-3536.2020.11.045

登录浏览全文

4963

注册一个新账户忘记密码

参考文献

原文顺序 | 出版日期 | 本文引用

[1] Fujishima A,Honda K.Electrochemical photolysis of water at a semiconductor electrode[J].Nature,1972,238(5358):37.
[2] Hoffmann M R,Martin S T,Choi W,et al.Environmental applications of semiconductor photocatalysis[J].Chemical Reviews,1995,95(1):69-96.
[3] Iancu V,Baia L,Tarcea N,et al.Towards TiO₂Ag porous nanocomposites based SERS sensors for chemical pollutant detection[J].Journal of Molecular Structure,2014,1073:51-57.
[4] Fu Y,Viraraghavan T.Fungal decolorization of dye wastewaters:a review[J].Bioresource Technology,2001,79(3):251-262.
[5] Ao C H,Lee S C,Yu J Z,et al.Photodegradation of formaldehyde by photocatalyst TiO₂∶effects on the presences of NO,SO₂ and VOCs[J].Applied Catalysis B:Environmental,2004,54(1):41-50.
[6] 李京波,盖艳琴,康俊,等.新型半导体深能级掺杂机制研究[J].科学通报,2018,63(63):365.
[7] Asahi R,Morikawa T,Irie H,et al.Nitrogen-doped titanium dioxide as visible-light-sensitive photocatalyst:designs,developments,and prospects[J].Chemical Reviews,2014,114(19):9824-9852.
[8] Kumar S G,Devi L G.Review on modified TiO₂ photocatalysis under UV/visible light:selected results and related mechanisms on interfacial charge carrier transfer dynamics[J].The Journal of Physical Chemistry A,2011,115(46):13211-13241.
[9] Fujishima A,Zhang X,Tryk D A.TiO₂ photocatalysis and related surface phenomena[J].Surface Science Reports,2008,63(12):515-582.
[10] Rahman K A,Bak T,Atanacio A,et al.Toward sustainable energy:photocatalysis of Cr-doped TiO₂:2.effect of defect disorder[J].Ionics,2018,24(2):327-341.
[11] Dvoranova D,Brezova V,Mazúr M,et al.Investigations of metal-doped titanium dioxide photocatalysts[J].Applied Catalysis B:Environmental,2002,37(2):91-105.
[12] Asahi R,Morikawa T,Ohwaki T,et al.Visible-light photocatalysis in nitrogen-doped titanium oxides[J].Science,2001,293(5528):269-271.
[13] 康华.锌和硅共掺杂二氧化钛纳米晶的光催化性能及其增强机制[J].工业催化,2011,19(8):32-35.
[14] 徐恩华.InGaN量子阱太阳能电池的理论效率计算[D].银川:宁夏大学,2012.
[15] Stucchi M,Bianchi C L,Argirusis C,et al.Ultrasound assisted synthesis of Ag-decorated TiO₂ active in visible light[J].Ultrasonics Sonochemistry,2018,40:282-288.
[16] An N,Ma Y,Liu J,et al.Enhanced visible-light photocatalytic oxidation capability of carbon-doped TiO₂ via coupling with fly ash[J].Chinese Journal of Catalysis,2018,39(12):1890-1900.
[17] Xin B,Jing L,Ren Z,et al.Effects of simultaneously doped and deposited Ag on the photocatalytic activity and surface states of TiO₂[J].The Journal of Physical Chemistry B,2005,109(7):2805-2809.
[18] Kokate M,Garadkar K,Gole A.Zinc-oxide-silica-silver nanocomposite:unique one-pot synthesis and enhanced catalytic and anti-bacterial performance[J].Journal of Colloid and Interface Science,2016,483:249-260.
[19] 孙晓艺,李金钰,刘辉,等.含硅宽禁带聚合物的合成及其光电性能研究[J].高分子学报,2018,2(2):284-294.
[20] Goharshadi E K,Azizi-Toupkanloo H.Silver colloid nanoparticles:ultrasound-assisted synthesis,electrical and rheological properties[J].Powder Technology,2013,237:97-101.
[21] Wang Dan,Zhao Linxia,Zhang Hui,et al.Study on morphological distribution of photogenerated superoxide radicals produced by different crystal titanium dioxide[J].Chinese Journal of Analytical Chemistry,2017,12(45):1882-1887.
[22] Low J,Qiu S,Xu D,et al.Direct evidence and enhancement of surface plasmon resonance effect on Ag-loaded TiO₂ nanotube arrays for photocatalytic CO₂ reduction[J].Applied Surface Science,2018,434:423-432.