Sb2S3纳米粒子修饰ZnO纳米片微纳分级结构的光电化学性能

采用恒电位方法,选择氯化钾和乙二胺(EDA)为添加剂,在氧化铟锡(ITO)导电玻璃上制备了高度有序的ZnO纳米片阵列,通过二次电沉积得到了ZnO纳米片上生长纳米棒的微纳分级结构.利用化学浴沉积法在ZnO基底上沉积Sb₂S₃纳米粒子制备出了Sb₂S₃/ZnO纳米片壳核结构和Sb₂S₃/ZnO微纳分级壳核结构.利用扫描电子显微镜(SEM)、X射线衍射(XRD)、紫外-可见(UV-Vis)吸收光谱、瞬态光电流等对其形貌、结构组成和光电化学性能进行了表征和分析.结果表明, Sb₂S₃/ZnO纳米片上生长纳米棒分级壳核结构的光电流明显高于Sb₂S₃/ZnO纳米片壳核结构.在Sb₂S₃/ZnO纳米片壳核结构和Sb₂S₃/ZnO微纳分级壳核结构的基础上旋涂一层P3HT薄膜形成P3HT/Sb₂S₃/ZnO复合结构,以上述复合结构薄膜为光活性层组装成杂化太阳电池,其中, P3HT/Sb₂S₃/ZnO分级壳核结构杂化太阳电池的能量转换效率最高,达到了0.81%.     

Sb2S3纳米丝的合成及杂化太阳电池研究

利用溶剂热方法制备出高质量的Sb₂S₃纳米丝, 并将其与聚(2-甲氧基-5-(2-乙基己氧基)-1,4-对苯乙炔)(MEH-PPV)共混制备成体型结构聚合物太阳电池.利用X射线衍射、扫描电子显微镜、透射电子显微镜和紫外-可见吸收光谱对Sb₂S₃纳米丝进行表征, 利用电流-电压(J-V)测试和电池的光电转换效率(IPCE)谱研究了Sb₂S₃纳米丝含量对Sb₂S₃/MEH-PPV共混体型结构太阳电池性能的影响.结果表明, 合成的Sb₂S₃纳米丝直径为60~70 nm, 长度为4~6 μm, 沿[001] 晶向生长, 在紫外-可见光区有较强的吸收, 光学带隙为1.57 eV.电池性能测试结果表明, Sb₂S₃纳米丝作为辅助光吸收材料及有效的电子传输材料, 提高了对可见光的利用率; Sb₂S₃的补充吸收作用使Sb₂S₃/MEH-PPV共混电池具有一定的宽谱响应特点; 与不含Sb₂S₃的电池相比, Sb₂S₃/MEH-PPV共混电池中增加的MEH-PPV/Sb₂S₃界面提高了光生激子分离效率, 从而提高了电池的效率.     

异质结界面修饰对TiO2/P3HT杂化太阳电池光电性能的增强作用

采用水热法在F-SnO₂(FTO)导电玻璃上制备了一维TiO₂纳米棒阵列, 将一种两亲有机三苯胺染料M分子吸附在其表面, 进而旋涂有机聚合物聚3-己基噻吩P3HT, 构建结构为FTO/TiO₂/M/P3HT/PEDOT:PSS/Au的杂化太阳电池. 瞬态光电流谱反映在杂化电极中存在pn异质结. 接触角测试表明TiO₂表面吸附有机M分子后, 亲水性表面转变为疏水性表面, 利于与聚合物P3HT的进一步接触; 稳态荧光发射光谱表明经修饰的杂化电极的荧光发射强度降低, 由荧光衰减曲线拟合得到的荧光寿命降低, 说明在TiO₂与P3HT之间存在有效的电荷转移, 电荷复合被抑制. 电化学阻抗分析表明界面修饰后电子复合电阻和电子寿命增大. 电池的特性参数均比界面修饰前有所提高, 光电转换效率为1.61%. 另外, 对该电池的工作机理、电荷传输过程进行了初步探讨.     

热退火气氛对溶液法制备的Sb2S3薄膜组成、结构及光伏性能的影响

采用化学浴(CBD)法在TiO₂薄膜表面制备结晶性Sb₂S₃膜层, 获得了TiO₂/Sb₂S₃平板异质结, 并结合聚[2,6-{4,4-双-(2-乙基己基)-4H-环戊并[2,1-b;3,4-b']-二噻吩}-交替-4,7-(2,1,3-苯并噻二唑)](PCPDTBT)空穴传输层和MoO₃电极界面修饰层, 制备了FTO/TiO₂/Sb₂S₃/PCPDTBT/MoO₃/Au平板结构太阳能电池, 研究了CBD方法中热退火气氛对Sb₂S₃薄膜的组成、 结构及光伏性能的影响. 结果表明, 在N₂气氛下退火时, 所得的Sb₂S₃膜层不致密且含有Sb₂O₃杂相, 电池效率仅为0.90%; 而在N₂-S气氛下退火时, 硫会与杂相Sb₂O₃发生反应生成Sb₂S₃, 进而得到纯净、 致密、 平整的结晶Sb₂S₃膜层. 在平板结构太阳能电池中, 光生空穴对电池光电流的产生有明显的贡献; 随着Sb₂O₃杂相的消除, Sb₂S₃薄膜中载流子的复合减少且传输速率增大, 使太阳能电池器件中电子与空穴的收集效率和短路电流显著提高, 电池效率提高了1.34倍, 达到2.04%.     

回流法合成硫化锑纳米棒及其光催化性能研究

以三氯化锑(SbCl₃)、硫粉(S)和硼氢化钠(NaBH₄)为原料, 1,2-丙二醇(C₃H₈O₂)作溶剂, 用回流法成功合成了Sb₂S₃纳米棒. 用XRD, EDS, SEM, TEM, HRTEM, SAED以及UV-Vis等手段对所制备产品的晶型、成分、形貌和光学特性进行了表征|以太阳光为光源、亚甲基蓝为目标降解物评价了Sb₂S₃纳米棒的光催化活性. 结果表明, 经186 ℃回流15 h可得到直径约为78～180 nm、长度达2～5 μm的正交晶系的Sb₂S₃单晶纳米棒. 经计算, 其晶胞参数a＝1.124 nm, b＝1.138 nm, c＝0.384 nm. UV-Vis分析表明, Sb₂S₃纳米棒为半导体材料, 其带隙能量为1.52 eV. 光催化性能测试表明, 所制备的Sb₂S₃纳米棒在太阳光下对亚甲基蓝具有较高的光催化降解率, 经20 min降解, 亚甲基蓝的降解率达84.31%, 表现出明显的可见光活性. 加入的PVP对控制Sb₂S₃的形貌有重要的作用. 另外, 还讨论了Sb₂S₃ 纳米棒可能的形成机理.     

P3HT/CdS/TiO2/ZnO一维有序核壳式纳米棒阵列的构制及其在杂化太阳电池中的应用研究

采用恒电位法在铟锡氧化物导电玻璃(ITO)上制备了高度有序一维ZnO纳米棒阵列,将ZnO纳米棒阵列在TiO2溶胶中采用提拉法制备出了一维TiO2/ZnO核壳式纳米棒阵列.在一维TiO2/ZnO核壳式纳米棒阵列上电沉积CdS纳米晶得到一维CdS/TiO2/ZnO核壳式纳米棒阵列,然后在一维CdS/TiO2/ZnO核壳式纳米棒阵列上电沉积聚3-己基噻吩(P3HT)薄膜得到P3HT/CdS/TiO2/ZnO核壳式纳米结构薄膜.以该纳米结构薄膜电极为光阳极制备出新型纳米结构杂化太阳电池,研究了该类电池的光电转换性能,初步探讨了该类电池的工作机理.     

3D ZnIn2S4微球/1D TiO2纳米带异质结构的光催化降解和还原性能

首先采用溶剂热法和高温煅烧法制备1D TiO₂纳米带,其次利用溶剂热法将1D TiO₂纳米带均匀地穿插到片层结构组装而成的3D ZnIn₂S₄微球中,所形成的异质结构能有效抑制光生电子-空穴的复合。二元ZnIn₂S₄微球/TiO₂纳米带复合光催化剂在高浓度染料罗丹明B(RhB)的光降解和Cr(VI)的光还原实验中表现出优异的性能。在模拟太阳光照射下,ZnIn₂S₄/TiO₂纳米带光催化降解RhB和还原Cr(VI)的效率相较于纯TiO₂颗粒(10%,22%)、TiO₂纳米带(45%,40%)、ZnIn₂S₄(62%,65%)、ZnIn₂S₄/TiO₂颗粒(90%,91%)分别提高至100%和100%。最后,通过紫外-可见...     

LaNiO3/TiO2纳米管阵列的电化学制备及其光催化性能

利用脉冲电沉积与高温退火相结合的方法制备了镍酸镧(LaNiO₃)纳米颗粒负载的二氧化钛(TiO₂)纳米管阵列. 修饰于TiO₂纳米管阵列上的LaNiO₃纳米颗粒粒径小（< 10 nm）、分布均匀、负载量可控,一些LaNiO₃纳米颗粒沉积于TiO₂纳米管内. 紫外可见吸收光谱显示,LaNiO₃/TiO₂纳米管阵列的吸收带边较TiO₂纳米管阵列明显红移,可见光吸收明显增强. 可见光下光催化降解罗丹明B（RhB）的结果表明,脉冲循环沉积500次制得的LaNiO₃/TiO₂纳米管阵列的光催化活性最佳,其对RhB光催化降解速率是TiO₂纳米管阵列的3.5倍,并且表现出极好的光催化稳定性.     

P3HT修饰一维有序壳核式CdS/ZnO纳米棒阵列复合膜的光电化学性能

采用电化学方法在铟锡氧化物(ITO)导电玻璃上制备了高度有序的ZnO纳米棒阵列, 在ZnO纳米棒阵列上先后电化学沉积CdS纳米晶膜及聚3-己基噻吩(P3HT)薄膜得到P3HT修饰的一维有序壳核式CdS/ZnO纳米阵列结构, 并通过扫描电镜(SEM)、透射电镜(TEM)、X射线衍射(XRD)、能量散射X射线(EDX)等表征手段证实了该结构的形成. 以此纳米结构薄膜为光阳极组装新型半导体敏化太阳电池, 研究了CdS纳米晶膜的厚度和P3HT薄膜的沉积对电池光伏性能的影响, 初步探讨了电荷在电池结构中的传输机理, 结果表明, CdS纳米晶膜和P3HT薄膜的沉积有效地拓宽了光阳极的光吸收范围, 实验中电池的光电转换效率最高达到1.08%.     

TiO2-PTPAT纳米核/壳结构复合膜的制备及电致变色性能

通过水热法在氟掺杂氧化锡(FTO)导电玻璃基底上制备了垂直生长的二氧化钛(TiO₂)纳米棒阵列, 以TiO₂纳米棒阵列为模板采用电化学聚合法, 原位制备了TiO₂-聚三[2-(4-噻吩)苯]胺(PTPAT)纳米核/壳结构的复合薄膜, 相比于纯PTPAT薄膜, TiO₂-PTPAT复合薄膜显示出更好的电致变色(EC)性能. PTPAT薄膜在600 nm波长下的对比度为28%, 在1100 nm波长下的对比度为60%, 其褪色时间为3.86 s, 着色时间为5.52 s; TiO₂- PTPAT复合薄膜在600 nm波长下的对比度为43%, 在1100 nm波长下的对比度为79%, 其褪色时间为3.35 s, 着色时间为4.43 s, 表明核/壳复合结构薄膜的光学对比度和响应时间性能更加优异. 将PTPAT薄膜和TiO₂-PTPAT复合薄膜作为电致变色层组装成固态EC器件, 基于复合薄膜的器件具有更好的循环稳定性和更高的耐受电压. 复合薄膜在保持PTPAT薄膜原有的EC性能的基础上, 由于有序生长的纳米阵列结构的引入增加了薄膜的比表面积, 为电致变色过程中离子的掺杂和脱掺杂提供了更多有序通道, 从而加快了离子扩散速度. TiO₂阵列的引入也改善了聚合物薄膜与透明导电电极之间的界面结合情况, 从而提升了器件的稳定性.     

4.81%光电转换效率的全固态致密PbS量子点薄膜敏化TiO2纳米棒阵列太阳电池

A compact PbS quantum-dot thin film was prepared using the combination of TiO₂ nanorod arrays and 1, 2-ethanedithiol following the spin-coating assisted successive ionic layer absorption and reaction procedure. Solar cells with the novel structure of FTO/compact PbS quantum-dot thin film sensitized TiO₂ nanorod arrays/spiro-OMeTAD/Au were assembled. Subsequently, the influence of the length of TiO₂ nanorod arrays on the photovoltaic performance of all-solid-state compact PbS quantum-dot thin film sensitized solar cells was evaluated. The corresponding solar cells having TiO₂ nanorod array lengths of 290, 540, and 1040 nm achieved photoelectric conversion efficiencies (PCE) of 2.02%, 4.81%, and 1.95%, respectively. These results reveal that in order to achieve high PCE values with the all-solid-state quantum dot sensitized solar cells, it is very important to balance the hole diffusion length with the loading amount of quantum-dots.     

微波辅助快速制备2D/1D ZnIn2S4/TiO2 S型异质结及其光催化制氢性能

The threat and global concern of energy crises have significantly increased over the last two decades. Because solar light and water are abundant on earth, photocatalytic hydrogen evolution through water splitting has been considered as a promising route to produce green energy. Therefore, semiconductor photocatalysts play a key role in transforming sunlight and water to hydrogen energy. To date, various photocatalysts have been studied. Among them, TiO₂ has been extensively investigated because of its non-toxicity, high chemical stability, controllable morphology, and high photocatalytic activity. In particular, 1D TiO₂ nanofibers (NFs) have attracted increasing attention as effective photocatalysts because of their unique 1D electron transfer pathway, high adsorption capacity, and high photoinduced electron–hole pair transfer capability. However, TiO₂ NFs are considered as an inefficient photocatalyst for the hydrogen evolution reaction (HER) because of their disadvantages such as a large band gap (~3.2 eV) and fast recombination of photoinduced electron–hole pairs. Therefore, the development of a high-performance TiO₂ NF photocatalyst is required for efficient solar light conversion. In recent years, several strategies have been explored to improve the photocatalytic activity of TiO₂ NFs, including coupling with narrow-bandgap semiconductors (such as ZnIn₂S₄). Recently, microwave (MW)-assisted synthesis has been considered as an important strategy for the preparation of photocatalyst semiconductors because of its low cost, environment-friendliness, simplicity, and high reaction rate. Herein, to overcome the above-mentioned limiting properties of TiO₂ NFs, we report a 2D/1D ZnIn₂S₄/TiO₂ S-scheme heterojunction synthesized through a microwave (MW)-assisted process. Herein, the 2D/1D ZnIn₂S₄/TiO₂ S-scheme heterojunction was constructed rapidly by using in situ 2D ZnIn₂S₄nanosheets decorated on 1D TiO₂ NFs. The loading of ZnIn₂S₄ nanoplates on the TiO₂ NFs could be easily controlled by adjusting the molar ratios of ZnIn₂S₄ precursors to TiO₂ NFs. The photocatalytic activity of the as-prepared samples for water splitting under simulated solar light irradiation was assessed. The experimental results showed that the photocatalytic performance of the ZnIn₂S₄/TiO₂ composites was significantly improved, and the obtained ZnIn₂S₄/TiO₂ composites showed increased optical absorption. Under optimal conditions, the highest HER rate of the ZT-0.5 (molar ratio of ZnIn₂S₄/TiO₂= 0.5) sample was 8774 μmol·g^-1·h^-1, which is considerably higher than those of pure TiO₂ NFs (3312 μmol·g^-1·h^-1) and ZnIn₂S₄nanoplates (3114 μmol·g^-1·h^-1) by factors of 2.7 and 2.8, respectively. Based on the experimental data and Mott-Schottky analysis, a possible mechanism for the formation of the S-scheme heterojunction between ZnIn₂S₄ and TiO₂ was proposed to interpret the enhanced HER activity of the ZnIn₂S₄/TiO₂heterojunctionphotocatalysts.      

棒状金属有机框架结构PCN-222(Cu)/TiO2复合材料的制备及其高效光催化CO2还原性能

The photocatalytic reduction of CO₂ has attracted considerable attention owing to the dual suppression of environmental pollution and energy shortage. The technology uses solar energy to convert carbon dioxide into hydrocarbon fuel, which is of great significance for achieving the carbon cycle. The development of low-cost photocatalytic materials is critical to achieving efficient solar energy to fuels conversion. One of the most commonly employed photocatalysts is TiO₂. However, it suffers from broad band gap as well as the recombination of photo-excited holes and electron. Hence, in this work, we report the photochemical reduction of CO₂ using rod-like PCN-222(Cu)/TiO₂ composites as photocatalyst through a simple hydrothermal method, in which TiO₂ nanoparticles are anchored at the interface of the SiC rod PCN-222(Cu). Multiple characterization techniques were used to analyze the structure, morphology, and properties of the PCN-222(Cu)/TiO₂ composite. A series of characterizations including X-ray diffraction (XRD), scanning electron microscopy (SEM), diffuse reflectance spectroscopy (DRS), Fourier-transform infrared spectroscopy, photo-electrochemical, and photoluminescence (PL) confirm the successful preparation of PCN-222(Cu)/TiO₂ composites. SEM reveals that the TiO₂ nanoparticles are uniformly distributed on the surface of the rod-shaped PCN-222(Cu)/TiO₂. XRD results show that PCN-222(Cu) and PCN-222(Cu)/TiO₂ composite photocatalysts with good crystal structure were successfully synthesized. According to the DRS results, the prepared PCN-222(Cu)/TiO₂ composite samples exhibit characteristic absorption peaks of metalloporphyrins in the visible region. PL spectroscopy, transient photocurrent response, and electrochemical impedance spectroscopy further confirm that the rod-like PCN-222(Cu)/TiO₂ samples have high electron-hole pair separation efficiency. By controlling the mass ratio of PCN-222(Cu) and TiO₂, the photocatalytic CO₂ reduction performance test shows that the 10% PCN-222(Cu)/TiO₂ composite achieves optimal catalytic performance, yielding 13.24 μmol·g⁻¹·h⁻¹ CO and 1.73 μmol·g⁻¹·h⁻¹ CH₄, respectively. All the rod-like PCN-222(Cu)/TiO₂ composites exhibit better photocatalytic CO₂ activity than that of TiO₂ nanoparticles or PCN-222(Cu) under the illumination of xenon lamps, which is attributed to charge transport and electron-hole separation capabilities. After three test cycles, the catalytic activity of PCN-222(Cu)/TiO₂ photocatalyst was virtually unchanged. The reduction yield of the catalyst increased for 8 h under continuous illumination, indicating that PCN-222(Cu)/TiO₂ composites have acceptable stability. The estimation of the band gap curve and the Mote-Schottky curve test show that the lowest unoccupied molecular orbital position of PCN-222(Cu) is more negative than the TiO₂ of the conduction band; hence, a possible photocatalytic reaction mechanism of the PCN-222(Cu)/TiO₂ composite is proposed. This study provides a new strategy for the integration of metal-organic frameworks and oxide semiconductors to construct efficient photocatalytic systems.     

Electronic Structure Effect of Polythiophene Derivatives and Nano N-Zn-Ag/TiO2 on Performance of Organic Thin Film Solar Cell

Nanocrystal N-Zn-Ag/TiO₂ powders were prepared with N-Zn/TiO₂ by photo deposition method. A series of pure polymers P3HT[poly(3-hexylthiophene)], P3OT[poly(3-octylthiophene)], P3DT[poly(3-decylthiophene)] and P3DDT[poly(3-dodecylthiophene)], was synthesized, which were used to synthesize p-n type semiconductor materials P3HT/N-Zn-Ag-TiO₂, P3OT/N-Zn-Ag-TiO₂, P3DT/N-Zn-Ag-TiO₂ and P3DDT/N-Zn-Ag-TiO₂ by in situ che-mical method. X-Ray diffraction(XRD) and infrared(IR) spectroscopy showed the structure of the polymers and complexes. Ultraviolet-visible(UV-Vis) spectra and cyclic voltammograms(CV) showed the optical and electronic performance of the polymers and complexes. Two new single and double organic thin film heterojunction solar cells were prepared with the above mentioned synthesized powders as raw materials. Current-voltage(I-V) measurements indicate that the conversion efficiency of the single organic thin film heterojunction solar cell is higher than that of the double organic thin film heterojunction solar cells. Single organic thin film heterojunction solar cells based on P3DT/N-Zn-Ag-TiO₂ can get a photoelectric conversion efficiency of 0.0408%. The performance of electronic transform between electron donor and acceptor on organic thin film solar cells was researched.     

Hierarchical TiO2 Flower-spheres with Large Surface Area and High Scattering Ability: an Excellent Candidate for High Efficiency Dye Sensitized Solar Cells

Hierarchical TiO₂ flower-spheres assembled from porous nanosheets-stacked of nanoparticles were synthesized by a simple hydrothermal method with one-step. The as-prepared TiO₂ flower-spheres showed a diameter range from 200 nm to 550 nm and a large surface area of 188 m²/g. A double layer photoanode made of P25 nanoparticles and as-prepared TiO₂ flower-spheres was fabricated for the dye sensitized solar cells(DSSCs). The efficient light scattering and dye absorption of the photoanode can be attributed to the top-layer of hierarchical TiO₂ flower-spheres. DSSCs based on the double layers photoanode exhibit a higher energy conversion efficiency of 8.11% with a short-circuit photocurrent density of 17.87 mA/cm², indicating that there is an increase of 38% in the conversion efficiency compared to those based on electrode P25(5.91%, 14.09 mA/cm²).