n型衬底上双面HIT太阳电池背场的模拟优化

采用美国滨州大学研发的AMPS-1D软件,模拟了背场对TCO/a-Si∶ H(p+)/a-Si∶ H(i)/c-Si(n) /a-Si∶ H(i) /a-Si∶ H(n+)/TCO双面HIT异质结太阳电池光伏特性的影响.结果表明在背场掺杂浓度NB≥1×1018cm-3时,带隙在1.60～ 1.92 eV范围内的宽带隙薄膜硅材料比较适合作为双面HIT太阳电池的背场.模拟中还发现,背场n+层掺杂浓度对太阳电池性能的影响要受到该层隙间态密度的制约,隙间态密度越大,则对背场掺杂浓度的要求越高.     

高效背结异质结太阳电池硼掺杂非晶硅发射极研究

晶硅/非晶硅异质结(HJT)太阳电池由于具有高开压、高转换效率和低温度系数等优点而备受关注，其中硼掺杂p型非晶硅(p-a-Si∶H)发射极是高转换效率电池中不可忽视的重要部分，改变其硼掺杂浓度，可以调节p-layer薄膜的电学特性，从而直接影响电池转换效率。本文采用等离子体增强化学气相沉积(PECVD)设备制备HJT太阳电池，通过改变B₂H₆的掺杂浓度，对电池中p-a-Si∶H层进行优化，使HJT电池获得0.75%的相对效率提升。进一步地，将发射极设置为梯度掺杂的双层结构，经过优化，少子寿命(@Δn=5×10¹⁵ cm^-3)和隐开路电压(@1-Sun)分别提升400μs和3 mV,最终具有梯度掺杂发射极的电池其平均效率相对提升2.03%,主要表现为FF和V_oc的明显增加，实现了高效HJT电池p型发射极的工艺优化。     

基于AFORS-HET的单层MoS2(n)/a-Si(i)/c-Si(p)/μc-Si(p+)异质结太阳能电池模拟

设计了单层MoS2 (n)/a-Si(i)/c-Si(p)/μc-Si(p+)异质结太阳能电池结构,采用AFORS-HET模拟软件模拟了背场层的带隙、掺杂浓度和缺陷密度等参数对开路电压、短路电流、填充因子和转化效率的影响.结果 显示,背场层带隙在1.5 ～1.7 eV之间,背场层的掺杂浓度大于1×1018 cm-3时,该结构的太阳能电池有比较稳定的表现.缺陷密度增加时,太阳能电池效率随着缺陷密度的对数线性减小,当控制缺陷密度在1011 cm-3以下时,可以获得大于24.10;的转化效率,缺陷密度为109 cm-3时,可以获得最高29.08;的转换效率.最后研究了背场层对该结构太阳能电池的作用,结果显示有效控制缺陷密度时,背场层的添加对电池效率的提升很明显.     

模拟分析发射层带隙及缺陷态对HIT太阳电池性能的影响

运用美国滨州大学研发的AMPS-1D程序,模拟计算了发射层对n型衬底上有背场的非晶硅/单晶硅异质结太阳电池光伏性能的影响.结果表明当发射层隙间缺陷态密度大于发射层掺杂浓度并达到一定值时,太阳电池的开路电压和填充因子将大幅度降低,从而导致电池的转换效率迅速衰减.发射层的带隙越大,电池的短路电流越大,而带尾宽度越宽,电池的开路电压越低,二者应达到最佳的匹配值才能使太阳电池达到更高的转换效率.     

ZnO(n)/ZnSe(i)/c-Si(p)异质结太阳电池的模拟研究

近年来,HIT(heterojunction with intrinsic thin-layer)结构太阳能电池由于具有转化效率高和可低温生产等优点获得了广泛的关注,但是转化原材料成本高、生产技术条件苛刻和缺陷态控制等问题制约了其进一步的发展。本文采用AFORS-HET软件模拟了ZnO(n)/ZnSe(i)/c-Si(p)异质结太阳电池结构吸收层掺杂浓度、缺陷密度和界面缺陷态密度等参数对该结构短路电流、开路电压、填充因子和光电转换效率的影响。优化后的结果显示,当吸收层掺杂浓度为1×10²¹ cm^-3,ZnO层和c-Si层缺陷密度小于10¹⁷ cm^-3时,ZnSe/c-Si界面缺陷密度小于10²⁵ cm^-3时,该结构太阳能电池光电转换效率可达24.29%。     

非对称电极和绒面结构对晶硅电池暗Ⅰ～Ⅴ特性的影响

利用有限差分法求解半导体器件基本方程的方法,通过改变栅线电极和衬底掺杂浓度,研究了织构结构和非对称电极对晶硅电池暗Ⅰ～Ⅴ特性的影响。结果表明:衬底掺杂浓度决定了织构结构晶硅电池的pn结性质,并对其暗Ⅰ～Ⅴ特性曲线产生具有重要影响;栅线电极覆盖绒面金字塔比率相同时,晶硅电池的暗Ⅰ～Ⅴ特性曲线将出现相同的分区特性,且理想因子随绒面金字塔的增加而微幅增加;栅线电极与电池底面电极构成二极管的理想因子,随金字塔周期数增加而增大,是决定晶硅电池暗Ⅰ～Ⅴ特性曲线性质的关键因素;当衬底掺杂浓度大于等于1×10~(17)时,暗Ⅰ～Ⅴ特性曲线可分成三个变化区域;当衬底掺杂浓度小于1×10~(17)时,暗Ⅰ～Ⅴ特性曲线可分成四个变化区域;同一偏压下,衬底掺杂浓度越高,暗电流越小。此外,利用pn结处于不同偏压下的总电流密度分布,详细分析了不同区域形成的物理机制。     

非对称电极和绒面结构对晶硅电池暗I～V特性的影响

利用有限差分法求解半导体器件基本方程的方法,通过改变栅线电极和衬底掺杂浓度,研究了织构结构和非对称电极对晶硅电池暗I～V特性的影响.结果表明:衬底掺杂浓度决定了织构结构晶硅电池的pn结性质,并对其暗I～V特性曲线产生具有重要影响;栅线电极覆盖绒面金字塔比率相同时,晶硅电池的暗I～V特性曲线将出现相同的分区特性,且理想因子随绒面金字塔的增加而微幅增加;栅线电极与电池底面电极构成二极管的理想因子,随金字塔周期数增加而增大,是决定晶硅电池暗I～V特性曲线性质的关键因素;当衬底掺杂浓度大于等于1×1017时,暗I～V特性曲线可分成三个变化区域;当衬底掺杂浓度小于1×1017时,暗I～V特性曲线可分成四个变化区域;同一偏压下,衬底掺杂浓度越高,暗电流越小.此外,利用pn结处于不同偏压下的总电流密度分布,详细分析了不同区域形成的物理机制.     

原子层沉积Sn掺杂ZnO薄膜结构及光电性能的研究

采用原子层沉积方法以臭氧为氧源,分别在Si和K-9玻璃衬底沉积Sn掺杂ZnO薄膜.系统研究了Sn掺杂浓度对ZnO薄膜成分、晶体结构及光电性能的影响.XRD分析表明:所制备SnZO薄膜具有垂直于衬底表面的c轴择优取向.XPS分析表明:在ZnO中掺杂离子以Sn4+形式存在.Hall分析表明Sn是一种有效的施主掺杂元素,其通过置换Zn2+位置释放导电电子.当Sn掺杂浓度为1.8at;时,Hall测试表明ZnO薄膜具有最低电阻率为9.5×10-4Ω·cm,载流子浓度达到最高值为3.2×1020 cm-3,进一步增加Sn浓度使得ZnO薄膜电学性能变差.SnZO薄膜在可见光区域的光透过率超过85;,光学带隙值由未掺杂ZnO的3.26 eV增加到5.7at; Sn掺杂时3.54 eV.     

全TOPCon电池正面多晶硅层硼掺杂工艺

为提升隧穿氧化层钝化接触(TOPCon)电池光电转换效率,本文通过高温扩散在n型TOPCon电池正面制作p型隧穿氧化层钝化接触结构,提升发射极钝化性能,减少正面金属复合。本文研究了不同沉积时间、推进温度、推进时间等工艺参数对实验样品钝化性能及掺杂曲线的影响。实验结果表明,当沉积时间为1 500 s,推进温度为920℃,推进时间为20 min时,掺硼多晶硅层可获得较优的钝化性能及掺杂浓度,其中样品多晶硅层硼掺杂浓度达到1.40×10²⁰ cm^-3,隐开路电压(iV_oc)大于720.0 mV。依据该参数制备的TOPCon电池光电转换效率可达23.89%,对应的短路电流密度为39.36 mA/cm²,开路电压(V_oc)达到726.4 mV,填充因子(FF)为83.54%。     

p型G aSb窗口层在热光伏电池中的应用研究

为了提高GaSb热光伏电池的转换效率,在电池结构中引入p+-GaSb窗口层,研究了生长基底、衬底温度和反应物源温度对p+-GaSb薄膜性能的影响,并优化了电池结构中p+-GaSb窗口层的厚度和掺杂浓度.实验结果表明,生长基底和温度等制备参数影响着p+-GaSb薄膜的结构特性和电学特性,而且,较薄的高掺杂p+-GaSb层有利于提高电池性能.通过测试和仿真,热光伏电池的转换效率达到9.49;(AM1.5测试)和20.34;(AFORS-HET仿真).     

First-principles coexistence simulations of supercooled liquid silicon

We perform first-principles coexistence simulations of the low-density and the high-density phases of supercooled liquid silicon and find a negative slope for the coexisting line in the temperature-pressure plane. Electron density maps and electron-localization function plots of the two phases of silicon show marked differences. The calculated differences suggest more localized electrons in the low-density liquid compared to the high-density liquid, coming from an increased population of covalent bonds, which further explain the calculated negative slope in the two phase coexistence regime. This is consistent with the presence of a pseudo-gap in low-density liquid silicon, absent in the high-density liquid which shows a metallic behavior.     

Triethyl ammonium salt of O,O′-bis(p-tolyl)dithiophosphate, [Et3NH]+[(4-MeC6H4O)2PS2]−

Triethyl ammonium Salt of O,O′-bis(p-tolyl)dithiophosphate and O,O′-bis(m-tolyl)dithiophosphate have been obtained by reaction of p- and m-cresol, respectively with P₂S₅ in toluene and have been characterized by elemental analysis, IR, ¹H and ³¹P NMR spectroscopy. The molecular structure of O,O′-bis(p-tolyl)dithiophosphate has been determined. Crystal data: [Et₃NH]⁺[(4-MeC₆H₄O)₂PS₂]⁻: Monoclinic, P2₁/c, a=15.2441(9) ?, b=10.415(2) ?, c=3.9726(9) ?, β=91.709(7)°, V=2217.5(1) ?⁻³, Z=4.Supplementary materials Additional material available from the Cambridge Crystallographic Data Centre (CCDC no. 600927 for [Et₃NH]⁺[(4-MeC₆H₄O)₂PS₂]⁻ comprises the final atomic coordinates for all atoms, thermal parameters, and a complete listing of bond distances and angles. Copies of this information may be obtained free of charge on application to The Director, 12 Union Road, Cambridge CB2 2EZ, UK (fax: +44-1223-336033; email: deposit@ccdc.cam.ac.uk or www:http://www.ccdc.cam.ac.uk).     

Crystal structures of thecis andtrans isomers of dithiahexahydro[3.3]metacyclophane

Structures of both thecis andtrans isomers of dithiahexahydro[3.3]metacyclophane, ?C₆H₄?CH₂SCH₂?C₆H₁₀?CH₂SCH₂?, have been determined, wherecis andtrans refer to the attachments to the cyclohexane ring. Thecis form crystallizes in the monoclinic space groupP2₁/c witha=8.4299(11)Å,b=21.772(2)Å,c=8.9724(13)Å, β=116.574(11)^o, andZ=4. Thetrans isomer packs into the monoclinic space groupP2₁ witha=8.159(16)Å,b=10.185(5)Å,c=9.558(2)Å, β=112.435(18)^o, andZ=2. The cyclohexane ring of thecis isomer is in the chair conformation, while the cyclohexane of thetrans isomer is found in a twisted boat conformation.     

CTAB与SDBS对碳酸锶粒子生长形态调控及机理研究

以表面活性剂CTAB和SDBS为化学添加剂,采用化学共沉淀法对碳酸锶晶体的生长形态进行调控,成功地制备出了实心的树枝状和花瓣为空心的花状碳酸锶粉体,并用X射线衍射(XRD)、扫描电子显微镜(SEM)和傅里叶变换红外光谱(FT-IR)等分析手段对样品进行了表征;最后重点对化学添加剂可能产生的影响机理进行了初步的探讨.结果表明,CTAB和SDBS在晶体生长的过程中能起到显著的影响作用,两者对粒子分散性能的作用效果相反,而且后者对晶体(013)和(213)晶面表面能降低的贡献明显大于前者.     

Crystal structure of Zn4Na(OH)6SO4Cl·6H2O

The structure of Zn₄Na(OH)₆SO₄Cl·6H₂O, a secondary mineral from Hettstedt, Germany, was determined by single-crystal X-ray diffraction. The crystals are hexagonal,a=8.413(8),c=13.095(24) Å, space group $P\bar 3$ , Z=2. The structure was refined to R=0.0554 and R_w=0.0903 for 970 reflections with I≥3σ(I). The structure can be described as zinc hydroxide layers perpendicular toc, from which sulfates and chlorides extend. The layers are held together by a system of hydrogen bonds involving hexaaquo Na⁺ ions which occupy the interlayer space.     

Synthesis and Crystal Structure of 5-[2-(6-bromonaphthalenyloxymethyl)]-3-(4-morpholinomethyl)-1,3,4-oxadiazole-2(3<Emphasis Type="Italic">H</Emphasis>)-thione

Abstract  The title compound, C₁₈H₁₈BrN₃O₃S, a derivative of 1,3,4-oxadiazole, crystallizes in the triclinic space group P-1 with unit cell parameters a = 6.8731(3), b = 8.9994(4), c = 15.7099(6) ?, α = 92.779(3)°, β = 130.575(3)°, γ = 107.868(4)°, Z = 2. The dihedral angle between the mean planes of the planar naphthyl and morpholine (chair) rings with the planar oxadiazol ring is 50.1(8) and 76.8(6)°, respectively. The planar naphthyl ring is twisted 52.2(5)° with the mean plane of the morpholine ring. A group of four intermolecular close contacts are observed between a bromine atom and hydrogen atoms from the closely packed naphthyl, morpholine and oxy–methyl groups in the unit cell. These molecular interactions in concert with an additional series of π–π stacking interactions that occur between the center of gravity of the two 6-membered rings of the naphthalene group influence the twist angles of each of these three groups. A MOPAC AM1 calculation of the conformation energy of the crystal structure [226.0128(9) kcal] compared to that of the minimum energy structure after geometry optimization [29.9744(1) kcal] reveals a significantly reduced value. The twist angles of the three groups above also change after the AM1 calculation giving support to the influence of both intermolecular C–H···Br short-range interactions and Cg π–π stacking interactions on these angles which therefore play a role in stabilizing crystal packing. Graphical Abstract  Crystal structure of 5-{[(6-bromonaphthalen-2-yl)oxy]methyl}-3-(morpholin-4-ylmethyl)-1,3,4-oxadiazole-2(3H)-thione, C₁₈H₁₈BrN₃O₃S, is reported and its geometric and packing parameters described and compared to a MOPAC computational calculation. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Crystal structure of irisolidone from the flowers of Pueraia lobata

Irisolidone (5,7-dihydroxy-6,4′-dimethoxyisoflavone) was isolated from the flowers of Pueraia lobata and its crystal structure was examined by X-ray single crystal diffraction. The crystal structure of irisolidone is monoclinic, space group P2₁/c with a = 15.491(9) ?, b = 7.895(4) ?, c = 13.321(7) ?, β = 110.546(9)° and Z = 4. Hydrogen bonding and aromatic π–π stacking assemble the title compound into a three-dimensional networking structure.     

Synthesis of spinacine and spinacine derivatives: crystal and molecular structures of Nπ-hydroxymethyl spinacine and Nα-methyl spinaceamine

The natural amino acid L-Spinacine (4,5,6,7-tetrahydro-1H-imidazo[4,5-c]pyridine-6-carboxylic acid) has been synthesized following a new pathway which gives a chemically and optically pure product with an excellent yield. The crystal structures of a synthetic intermediate, N^π-hydroxymethyl-spinacine, and a spinacine derivative, N^α-methyl-spinaceamine, have been investigated through X-ray diffraction: Spi(πMeOH)·H₂O, monoclinicP2 _i,a=8.571(1),b=6.682(1),c=8.588(1) Å, and β=94.67(1)^o. Spm(αMe)·2HCl·H₂O, triclinicP l,a=7.492(4),b=10.799(3),c=7.040(2) Å, α=91.88(2), β=98.36(3) and γ=73.34(3)^o. Spi(πMeOH) crystallizes with a water molecule and displays a zwitterionic character. The carboxylate group is in equatorial position and forms a short electrostatic interaction of 2.618(2) Å between one of its oxygens and the protonated nitrogen of the tetrahydropyridine ring. The crystal packing is assured by strong O?H???O, O?H???N, N?H???N intermolecular hydrogen bonds and C?H???O close contacts. The biprotonated compounds Spm(αMe) crystallizes with two Cl^? anions and a water molecule. The positive charge on the imidazole ring is delocalized on the conjugated moiety N=C?N. The crystal is built up by clusters formed by two biprotonated Spm(αMe) molecules, four Cl^? anions and two water molecules linked together by hydrogen bonds.