光谱学与光谱分析
光譜學與光譜分析
광보학여광보분석
SPECTROSCOPY AND SPECTRAL ANALYSIS
2014年
3期
625-629
,共5页
陆红波%刘小林%顾牡%倪晨%黄世明%刘波
陸紅波%劉小林%顧牡%倪晨%黃世明%劉波
륙홍파%류소림%고모%예신%황세명%류파
In/ZnO纳米粉%沉淀法%光致发光
In/ZnO納米粉%沉澱法%光緻髮光
In/ZnO납미분%침정법%광치발광
In/ZnO nanopowder%Precipitation%Photoluminescence
采用沉淀法制备In/ZnO纳米粉,通过XRD和光致发光谱等分析手段,详细讨论了不同In掺杂浓度、煅烧温度、反应物配比,以及沉淀剂种类对In/ZnO纳米粉微结构及光致发光特性的影响。实验结果表明,随着In掺杂浓度的增加,In/ZnO纳米粉的结晶性能和紫外发光强度因杂质缺陷的增多而逐渐减弱;同时观察到该发光峰位从389 nm红移至419 nm ,这可能是由于施主能级和导带的合并,以及杂质能级的潜在波动因素的影响所致。当煅烧温度从500℃升至600℃时,晶粒尺寸逐渐变大,紫外发射强度也因结晶性的增强而逐渐增大;当温度继续升高至800℃时,结晶性的进一步提高导致紫外发射强度增强,同时由于温度的升高使得ZnO晶格中离子动能变大而更易于产生氧空位,从而导致525 nm绿光发射也大大增强;当温度升高至1000℃时,紫外发射强度由于过多的氧空位而被极大抑制,此时525 nm绿光发射成为了发光主成份。随着反应物NH4 HCO3/Zn(NO3)2摩尔比的增加,由于反应速率的加快,使得In/ZnO纳米粉晶粒变小,紫外发光强度下降。沉淀剂种类(NH4 HCO3或NaOH)对前驱体粉末的结晶性能有着显著的影响,但对最终纳米粉产物的发光性能影响不大。
採用沉澱法製備In/ZnO納米粉,通過XRD和光緻髮光譜等分析手段,詳細討論瞭不同In摻雜濃度、煅燒溫度、反應物配比,以及沉澱劑種類對In/ZnO納米粉微結構及光緻髮光特性的影響。實驗結果錶明,隨著In摻雜濃度的增加,In/ZnO納米粉的結晶性能和紫外髮光彊度因雜質缺陷的增多而逐漸減弱;同時觀察到該髮光峰位從389 nm紅移至419 nm ,這可能是由于施主能級和導帶的閤併,以及雜質能級的潛在波動因素的影響所緻。噹煅燒溫度從500℃升至600℃時,晶粒呎吋逐漸變大,紫外髮射彊度也因結晶性的增彊而逐漸增大;噹溫度繼續升高至800℃時,結晶性的進一步提高導緻紫外髮射彊度增彊,同時由于溫度的升高使得ZnO晶格中離子動能變大而更易于產生氧空位,從而導緻525 nm綠光髮射也大大增彊;噹溫度升高至1000℃時,紫外髮射彊度由于過多的氧空位而被極大抑製,此時525 nm綠光髮射成為瞭髮光主成份。隨著反應物NH4 HCO3/Zn(NO3)2摩爾比的增加,由于反應速率的加快,使得In/ZnO納米粉晶粒變小,紫外髮光彊度下降。沉澱劑種類(NH4 HCO3或NaOH)對前驅體粉末的結晶性能有著顯著的影響,但對最終納米粉產物的髮光性能影響不大。
채용침정법제비In/ZnO납미분,통과XRD화광치발광보등분석수단,상세토론료불동In참잡농도、단소온도、반응물배비,이급침정제충류대In/ZnO납미분미결구급광치발광특성적영향。실험결과표명,수착In참잡농도적증가,In/ZnO납미분적결정성능화자외발광강도인잡질결함적증다이축점감약;동시관찰도해발광봉위종389 nm홍이지419 nm ,저가능시유우시주능급화도대적합병,이급잡질능급적잠재파동인소적영향소치。당단소온도종500℃승지600℃시,정립척촌축점변대,자외발사강도야인결정성적증강이축점증대;당온도계속승고지800℃시,결정성적진일보제고도치자외발사강도증강,동시유우온도적승고사득ZnO정격중리자동능변대이경역우산생양공위,종이도치525 nm록광발사야대대증강;당온도승고지1000℃시,자외발사강도유우과다적양공위이피겁대억제,차시525 nm록광발사성위료발광주성빈。수착반응물NH4 HCO3/Zn(NO3)2마이비적증가,유우반응속솔적가쾌,사득In/ZnO납미분정립변소,자외발광강도하강。침정제충류(NH4 HCO3혹NaOH)대전구체분말적결정성능유착현저적영향,단대최종납미분산물적발광성능영향불대。
In-doped ZnO nanopowders were prepared by precipitation .The influence of the processing parameters ,such as In do-ping concentration ,calcination temperature ,reactant ratio and type of precipitant on the grain size ,structure and photolumines-cence (PL) of In/ZnO nanopowders was detailed analyzed by using X-ray diffraction (XRD) and photoluminescence spectrum . The experimental results indicated that with the increase in the In doping level (the molar ratio of In3+ /Zn2+ increased from 0%to 5% ) ,the crystallization and the UV emission of ZnO nanopowders were reduced because of the increase of impurity defects . And the UV emission band would have a red-shift from 389 to 419 nm ,which could be resulted from the effects of merging of donor and conduction bands ,and potential fluctuations of impurity energy level .The calcination temperature will play an impor-tant role in synthesis of luminescence materials .When the calcination temperature was raised from 500 to 600 ℃ ,the grain size of In/ZnO nanopowder increased gradually ,and the dominated UV emission band was improved due to the enhanced crystalliza-tion of the nanopowder .If the temperature was raised up to 800 ℃ ,the crystallization of the sample was further improved ,lead-ing to an enhanced intensity of UV emission .Additionally ,near this temperature ,the oxygen vacancy is easier to be produced owing to the improvement of the kinetic energy for the ions in lattice ,which induces in the enhancement of the green emission band peaking at 525 nm .For the temperature up to 1 000 ℃ ,the UV emission band was suppressed due to the production of ex-cessive oxygen vacancy ,and the In/ZnO nanopowder exhibited a dominated green emission .The luminescence performance of the In/ZnO nanopowder is also much affected by the reactant ratio .The reaction rate is improved by the increase of the NH 4 HCO3/Zn(NO3 )2 molar ratio ,which will decrease both grain size of In/ZnO nanopowder and emission intensity of UV band .Further-more ,the effect of the precipitant on the luminescence was examined .It is obviously that the NH4 HCO3 and NaOH precipitants will remarkably affect the crystallization of the precursor powder ,but nearly have no effect on the luminescence property of the final nanopowder products .