本文選題：二氧化錫　切入點(diǎn)：第一性原理　出處：《濟(jì)南大學(xué)》2015年碩士論文

【摘要】：二氧化錫(SnO2)材料是一種優(yōu)秀的透明導(dǎo)電材料,也是一種典型的寬禁帶半導(dǎo)體材料,常溫下其帶隙為3.6eV,這使得它在以SnO2為基的半導(dǎo)體材料工業(yè)方面具有很好的發(fā)展?jié)摿�。將SnO2制成低維納米材料并對(duì)其進(jìn)行摻雜后所形成的新的材料具有高導(dǎo)電性、高透光率、高紫外光吸收能力以及較強(qiáng)的紅外反射率等性能,這更加拓寬了其在光電領(lǐng)域的應(yīng)用價(jià)值。本論文以SnO2為基材料,運(yùn)用基于密度泛函理論的第一性原理全電勢(shì)線性綴加平面波法和投影綴加平面波法,在廣義梯度近似(GGA)下伴隨著PBE交換關(guān)聯(lián)函數(shù)并應(yīng)用Wien2k和VASP軟件進(jìn)行計(jì)算。首先,我們計(jì)算了本征態(tài)塊體SnO2和Zr摻雜以及Zr、N共摻雜下SnO2材料的電子結(jié)構(gòu)、能帶和光學(xué)性質(zhì),研究結(jié)果表明摻雜Zr和N之后材料帶隙減小,材料的導(dǎo)電性增強(qiáng),并且光學(xué)吸收邊發(fā)生紅移,光學(xué)吸收能力也顯著增強(qiáng)。其次在塊體SnO2材料的基礎(chǔ)上構(gòu)建了“三明治”結(jié)構(gòu)的單層SnO2納米面模型,通過(guò)對(duì)其進(jìn)行第一性原理GGA_PBE的計(jì)算表明,本征態(tài)SnO2納米面的帶隙要大于塊體材料的帶隙,其仍然為直接帶隙半導(dǎo)體材料。然后我們對(duì)它進(jìn)行了Ag摻雜和O缺陷的研究,結(jié)果表明Ag摻雜之后材料的帶隙減小,導(dǎo)電性明顯增強(qiáng),光學(xué)性質(zhì)的研究標(biāo)明引入Ag之后材料在低能區(qū)域的吸收能力明顯增強(qiáng),并且隨著Ag摻雜濃度的不同材料的吸收能力也有所不同。然后通過(guò)SnO2面構(gòu)建出之字形(zigzag)和扶手椅形(armchair)的SnO2一維納米帶模型,研究了不同寬度下其帶隙的變化并對(duì)其進(jìn)行Ag摻雜的計(jì)算。研究結(jié)果表明SnO2納米帶是間接帶隙半導(dǎo)體,隨著納米帶寬度的增加,其帶隙也隨之發(fā)生變化,最后會(huì)趨向于一個(gè)穩(wěn)定的值。當(dāng)在納米帶中引入Ag之后,材料的導(dǎo)電性增強(qiáng),光學(xué)性質(zhì)的研究結(jié)果標(biāo)明引入Ag之后材料在在低能區(qū)域有較強(qiáng)的吸收能力。最后我們通過(guò)對(duì)之字形SnO2納米帶和扶手椅形SnO2納米帶進(jìn)行不同情況的H修飾來(lái)研究其電子結(jié)構(gòu)和性質(zhì)的變化,并且對(duì)其施加外部電場(chǎng)來(lái)調(diào)控其能帶結(jié)構(gòu)。研究結(jié)果顯示H修飾前的之字形納米帶和扶手型納米帶的帶隙均在電場(chǎng)調(diào)控下發(fā)生明顯的變化,對(duì)其進(jìn)行部分電荷密度的分析表明在電場(chǎng)作用下,材料表現(xiàn)出明顯的stark效應(yīng)。而H修飾后SnO2納米帶的帶隙發(fā)生變化,并且在加電場(chǎng)后表現(xiàn)出比較弱的stark效應(yīng)。更有趣的是,H修飾的之字形納米帶在外加電場(chǎng)的變化下出現(xiàn)了金屬-半導(dǎo)體-金屬的轉(zhuǎn)變。最后我們計(jì)算了不同邊緣構(gòu)型的SnO2納米帶的輸運(yùn)特性,得到了一些有意義的結(jié)果。
[Abstract]:Sno _ 2) is an excellent transparent conductive material and a typical wide band gap semiconductor material with a band gap of 3.6 EV at room temperature, which makes it have a good development potential in semiconductor material industry based on SnO2.The new materials made of SnO2 and doped with SnO2 have high conductivity, high transmittance, high ultraviolet absorption ability and strong infrared reflectivity.This further broadens its application value in the field of optoelectronics.In this paper, based on SnO2, the first principle full potential linear plus plane wave method and projection plus plane wave method are used based on density functional theory.Under the generalized gradient approximation (GGA), the PBE commutative correlation function is accompanied and calculated by Wien2k and VASP software.First of all, we calculate the electronic structure, band and optical properties of SnO2 materials doped with SnO2 and Zr and ZrN co-doped. The results show that the band gap decreases and the electrical conductivity increases after doping Zr and N.And the optical absorption edge is redshift, and the optical absorption ability is also significantly enhanced.Secondly, the monolayer SnO2 nano-surface model of "sandwich" structure is constructed on the basis of bulk SnO2 material. The results of first-principles GGA_PBE calculation show that the band gap of intrinsic SnO2 nano-surface is larger than that of bulk SnO2 nanoplane.It is still a direct band gap semiconductor material.Then we study the Ag doping and O defects. The results show that the band gap decreases and the electrical conductivity increases obviously after Ag doping. The optical properties show that the absorption ability of the material in the low energy region is obviously enhanced after the introduction of Ag.And the absorption capacity of different Ag doped materials is different.Then the one-dimensional SnO2 nanobelts model of zigzag (zigzag) and armchair (armchair) were constructed by SnO2 plane. The band gap changes at different widths were studied and the Ag doping calculation was carried out.The results show that SnO2 nanobelts are indirect band-gap semiconductors. With the increase of the width of nanobelts, the band gap also changes and tends to a stable value.When Ag was introduced into nanobelts, the electrical conductivity of the materials was enhanced, and the results of optical properties showed that the materials had a strong absorption capacity in the low energy region after the introduction of Ag.Finally, we study the changes of electronic structure and properties of zigzag SnO2 nanoliths and armchair SnO2 nanoliths by H modification in different conditions, and apply external electric field to regulate their band structure.The results show that the band gap of zigzag and armrest nanobelts before H modification are obviously changed under the control of electric field. The analysis of partial charge density shows that the material exhibits obvious stark effect under the action of electric field.After H modification, the band gap of SnO2 nanobelts changes, and the stark effect is weaker after the addition of electric field.What is more interesting is that H-modified zigzag nanobelts change from metal to semiconductor to metal under the change of external electric field.Finally, we calculate the transport characteristics of SnO2 nanobelts with different edge configurations, and obtain some meaningful results.
【學(xué)位授予單位】：濟(jì)南大學(xué)
【學(xué)位級(jí)別】：碩士
【學(xué)位授予年份】：2015
【分類號(hào)】：TB383.1;TQ134.32

【參考文獻(xiàn)】

相關(guān)期刊論文 前1條

1 金仁成;翁雪軍;王立鼎;張五金;;SnO_2(110)表面電子結(jié)構(gòu)的第一性原理[J];功能材料與器件學(xué)報(bào);2008年01期

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本文編號(hào)：1707317