聚乳酸/超导炭黑复合材料的制备及其对PM_(2.5)吸附的研究

以聚乳酸(PLA)以及超导炭黑(EC-600JD)为原料,利用静电纺丝技术制备了PLA/EC-600JD(PC600)纳米纤维膜并用于PM_(2.5)的吸附。利用扫描电镜(SEM)、热失重分析(TGA)以及X射线光电子能谱(XPS)等对吸附前后的纳米纤维膜进行了结构与吸附性能的表征。SEM和XPS的结果表明,PC600系列纳米纤维膜成功的吸附了PM_(2.5)颗粒;从TGA可知,加入少量的超导炭黑即可使纳米纤维膜的吸附性能显著提高。当EC-600JD的加入量为0.2%(质量分数)时,PC600-2的相对吸附量高达20.5%,与纯的PLA膜相比,吸附量提高了近3倍。     

碳材料在太阳能电池对电极中的研究进展

简要说明了太阳能电池对电极的作用,并阐述了铂对电极、镍对电极、聚合物对电极和氧化铜对电极目前的发展状况.碳材料具有良好的导电性能和催化性能,具有制备太阳能电池对电极的基本性质.详细论述了碳材料对电板的制备工艺及其性能参数,与其它对电极相比,碳材料制备的对电极导电性能好,光电转化率可达到铂电极的90%,优于其它材料制备的对电极,而且价格低廉,因此碳材料对电极具有广阔的发展前景.碳材料对电极是染料敏化太阳能电池的重要研究方向.     

染料敏化太阳能电池对电极的研究进展

对电极一直是染料敏化太阳能电池的重要组成部分,铂(Pt)对电极具有良好的性能,但高成本限制了它的应用,低成本、性能较好的碳对电极和导电聚合物对电极具有广阔的发展前景。开发性能稳定,成本低、催化活性高、制备工艺简单的染料敏化太阳能电池对电极材料是染料敏化太阳电池发展的必经过程。     

黑枸杞与石墨烯纳米片在染料敏化太阳能电池中的应用

从高原黑枸杞中提取染料, 利用紫外-可见吸收光谱和循环伏安方法研究不同pH染料的光电化学性能, 确定染料最佳pH。以石墨烯为原料制备不同含量乙基纤维素(EC)的石墨烯纳米片(GNs)对电极, 用电化学阻抗、循环伏安、塔菲尔极化曲线研究不同EC含量对GNs对电极电催化性能的影响。以最佳pH染料为光敏剂, 不同含量EC的GNs为对电极组装染料敏化太阳能电池在模拟太阳光下测试光电转换效率。结果表明, EC含量为10wt%时, GNs对电极有良好的电催化性。光电测试EC含量为10wt%的GNs对电极光电转换效率为0.92%, 接近Pt对电极(0.99%)。     

碳材料在染料敏化太阳能电池和钙钛矿太阳能电池对电极中的应用进展

染料敏化太阳能电池和钙钛矿太阳能电池是目前太阳能电池领域的研究热点,但这两种电池中使用的传统对电极材料,如Pt和Au等稀有且价格昂贵,不利于大规模量产。碳材料作为除Pt,Au等之外的另一种候选材料,其种类丰富且成本低廉,作为对电极应用在这两类电池中具有逐渐接近甚至超越传统电池的光电转换效率,表现出良好的应用前景。本文综述了作为两类电池对电极的碳材料具备的结构、性能及对电池光伏性能的影响,着重介绍各种形式的碳材料应用于对电极的最新研究进展,并指出现有研究存在的局限性与待解决的问题,讨论了碳材料对电极未来的研究方向。     

不同炭材料对电极对染料敏化太阳能电池性能的影响

分别以石墨/活性炭/炭黑/碳纳米管为原料,采用丝网印刷技术制备染料敏化太阳能电池(DSSC)的对电极。分析比较了各原料的孔结构、比表面积及各原料制膜的方块电阻对组装电池性能的影响。结果表明,对于制备DSSC对电极的原料而言,孔尺寸要有一定的分布范围,孔形状要求口径大于或至少等于体径;比表面积并非越大越好,还应考虑其内部孔结构;制膜的方块电阻并非是影响电池性能的决定性因素。另外,原料的颗粒形状及排布方式也影响电池的性能。笔者以比表面积31.163 m.2g-1、方块电阻12.5Ω/□的碳纳米管所制碳膜组装的电池性能最佳,光电转化效率达5.87%。     

染料敏化太阳能电池介孔石墨相C3N4对电极的制备及电催化性能研究

以氰胺为原料,通过硬模板法制备了介孔石墨相C_3N_4(mg-C_3N_4)。用mg-C_3N_4代替Pt制备染料敏化太阳能电池对电极,并对其电催化性能进行了研究。N2吸附数据表明所制备的mg-C_3N_4具有较高的比表面积(87.4m2/g)和较大孔体积(0.45cm3/g)。电化学阻抗谱分析表明所制备的mg-C_3N_4电极的电荷跃迁电阻为42.5Ω·cm2,证明mg-C_3N_4电极对I3-还原反应具有较高的电催化活性。以mg-C_3N_4电极作为对电极组装染料敏化太阳能电池,在100mW/cm2光照下(AM 1.5),电池的光电转换效率达到3.72%,比无孔石墨相C_3N_4对电极所组装染料敏化太阳能电池的光电转换效率提高了103%。     

石墨/TiO2共混碳薄膜对电极的电学与电化学性能研究

本文将石墨、TiO2纳米晶以及TiO2胶体共混,采用旋涂法制备了碳薄膜对电极,并用于组装染料敏化太阳能电池。采用场发射扫描电子显微镜观察薄膜的表面形貌,采用四探针电阻率测试仪、电化学交流阻抗图谱及太阳能电池综合测试仪对碳对电极的电学、电化学性质以及电池的光电性能分别进行测试;研究了薄膜厚度对碳对电极导电性能与电化学催化性能的影响。结果表明随着厚度增加,碳对电极的方块电阻和界面电荷传输电阻均变小,分别可达到26.6Ω.sp-1和11.8Ω.cm-2,而电池的填充因子及光电转换效率增大。当碳薄膜厚度为19.5μm时,光电转换效率可达到Pt对电极的70%。     

染料敏化太阳电池中铂金对电极的制备及性能之比较

分别采用了3种不同的方法制备了用于染料敏化TiO2太阳电池的铂金对电极，并分别以此3种铂金对电极组装染料敏化太阳电池，对比、分析和探讨了它们对光电转化性能的影响。结果表明：采用纳米粒子电沉积法与电化学电镀法制备的铂金对电极，具有较高的催化活性，以这两种方法制备的铂金对电极组装的DSSCs获得较好的光电转化性能，电池的光电转化效率分别为6．40％和6．63％，且采用纳米粒子电沉积法制备的铂金对电极铂金含量较低；而采用热分解法制备的铂金对电极来组装的DSSCs获得的光电性能相对较低，电池效率为5．58％。     

一步法热分解制备染料敏化太阳能电池Pt对电极

用旋涂热分解前驱H2PtCl6·6H2O溶液制备Pt/FTO对电极,研究了旋涂退火次数对Pt/FTO对电极的载铂量、透光率和组装的染料敏化太阳能电池光电性能的影响。结果表明,用5次旋涂退火的对电极组装的电池具有最佳的能量转换效率(6.78%),高于用传统的磁控溅射对电极组装的电池。基于在最佳光电性能情况下对电极的旋涂次数和载Pt量,进一步优化H2PtCl6?6H2O前驱液的浓度和使用体积。采用一步滴涂退火处理,得到了具有高透光性、低载Pt量和高的组装电池效率的Pt/FTO对电极。用此一步法制备的Pt/FTO对电极,组装成的电池能量转换效率达到6.92%。     

醋酸铅添加剂在印刷钙钛矿太阳能电池中的应用

印刷钙钛矿太阳能电池采用无机介孔骨架包覆有机无机杂化钙钛矿材料的器件结构,制备工艺简单,原材料成本低廉,且稳定性优异.然而,在介孔骨架中均匀沉积高质量的钙钛矿材料存在一定困难.本研究通过在典型钙钛矿材料甲胺铅碘(MAPbI3)前驱液中引入醋酸铅(Pb(Ac)2)作为添加剂,加快钙钛矿晶体的成核从而改善其在介孔骨架中的生...     

A Semitransparent Inorganic Perovskite Film for Overcoming Ultraviolet Light Instability of Organic Solar Cells and Achieving 14.03% Efficiency

Organic solar cells (OSCs) can be unstable under ultraviolet (UV) irradiation. To address this issue and enhance the power conversion efficiency (PCE), an inorganic‐perovskite/organic four‐terminal tandem solar cell (TSC) based on a semitransparent inorganic CsPbBr₃ perovskite solar cell (pero‐SC) as the top cell and an OSC as bottom cell is constructed. The high‐quality CsPbBr₃ photoactive layer of the planar pero‐SC is prepared with a dual‐source vacuum coevaporation method, using stoichiometric precursors of CsBr and PbBr₂ with a low evaporation rate. The resultant opaque planar pero‐SC exhibits an ultrahigh open‐circuit voltage of 1.44 V and the highest reported PCE of 7.78% for a CsPbBr₃‐based planar pero‐SC. Importantly, the devices show no degradation after 120 h UV light illumination. The related semitransparent pero‐SC can almost completely filter UV light and well maintain photovoltaic performance; it additionally shows an extremely high average visible transmittance. When it is used to construct a TSC, the top pero‐SC acting as a UV filter can utilize UV light for photoelectric conversion, avoiding the instability problem of UV light on the bottom OSC that can meet the industrial standards of UV‐light stability for solar cells, and leading to the highest reported PCE of 14.03% for the inorganic‐perovskite/organic TSC.     

Robust Tin‐Based Perovskite Solar Cells with Hybrid Organic Cations to Attain Efficiency Approaching 10%

The stability of a tin‐based perovskite solar cell is a major challenge. Here, hybrid tin‐based perovskite solar cells in a new series that incorporate a nonpolar organic cation, guanidinium (GA⁺), in varied proportions into the formamidinium (FA⁺) tin triiodide perovskite (FASnI₃) crystal structure in the presence of 1% ethylenediammonium diiodide (EDAI₂) as an additive, are reported. The device performance is optimized at a precursor ratio (GAI:FAI) of 20:80 to attain a power conversion efficiency (PCE) of 8.5% when prepared freshly; the efficiencies continuously increase to attain a record PCE of 9.6% after storage in a glove‐box environment for 2000 h. The hybrid perovskite works stably under continuous 1 sun illumination for 1 h and storage in air for 6 days without encapsulation. Such a tin‐based perovskite passes all harsh standard tests, and the efficiency of a fresh device, 8.3%, is certified. The great performance and stability of the device reported herein attains a new milestone for lead‐free perovskite solar cells on a path toward commercial development.     

Infrared Solution‐Processed Quantum Dot Solar Cells Reaching External Quantum Efficiency of 80% at 1.35 µm and Jsc in Excess of 34 mA cm−2

Developing low‐cost photovoltaic absorbers that can harvest the short‐wave infrared (SWIR) part of the solar spectrum, which remains unharnessed by current Si‐based and perovskite photovoltaic technologies, is a prerequisite for making high‐efficiency, low‐cost tandem solar cells. Here, infrared PbS colloidal quantum dot (CQD) solar cells employing a hybrid inorganic–organic ligand exchange process that results in an external quantum efficiency of 80% at 1.35 µm are reported, leading to a short‐circuit current density of 34 mA cm^?2 and a power conversion efficiency (PCE) up to 7.9%, which is a current record for SWIR CQD solar cells. When this cell is placed at the back of an MAPbI₃ perovskite film, it delivers an extra 3.3% PCE by harnessing light beyond 750 nm.     

Perovskite Solar Cells: From Materials to Devices

Perovskite solar cells based on organometal halide light absorbers have been considered a promising photovoltaic technology due to their superb power conversion efficiency (PCE) along with very low material costs. Since the first report on a long‐term durable solid‐state perovskite solar cell with a PCE of 9.7% in 2012, a PCE as high as 19.3% was demonstrated in 2014, and a certified PCE of 17.9% was shown in 2014. Such a high photovoltaic performance is attributed to optically high absorption characteristics and balanced charge transport properties with long diffusion lengths. Nevertheless, there are lots of puzzles to unravel the basis for such high photovoltaic performances. The working principle of perovskite solar cells has not been well established by far, which is the most important thing for understanding perovksite solar cells. In this review, basic fundamentals of perovskite materials including opto‐electronic and dielectric properties are described to give a better understanding and insight into high‐performing perovskite solar cells. In addition, various fabrication techniques and device structures are described toward the further improvement of perovskite solar cells.     

Ultraflexible and Lightweight Bamboo‐Derived Transparent Electrodes for Perovskite Solar Cells

Wearable devices are mainly based on plastic substrates, such as polyethylene terephthalate and polyethylene naphthalate, which causes environmental pollution after use due to the long decomposition periods. This work reports on the fabrication of a biodegradable and biocompatible transparent conductive electrode derived from bamboo for flexible perovskite solar cells. The conductive bioelectrode exhibits extremely flexible and light‐weight properties. After bending 3000 times at a 4 mm curvature radius or even undergoing a crumpling test, it still shows excellent electrical performance and negligible decay. The performance of the bamboo‐based bioelectrode perovskite solar cell exhibits a record power conversion efficiency (PCE) of 11.68%, showing the highest efficiency among all reported biomass‐based perovskite solar cells. It is remarkable that this flexible device has a highly bendable mechanical stability, maintaining over 70% of its original PCE during 1000 bending cycles at a 4 mm curvature radius. This work paves the way for perovskite solar cells toward comfortable and environmentally friendly wearable devices.     

具有2D-EDAPbI4薄覆盖层的环境稳定的FAPbI3基钙钛矿太阳能电池（英文）

二维(2D)卤化铅钙钛矿材料是钙钛矿太阳能电池(PSC)中最有前途的吸光材料之一,具有优异的稳定性和缺陷钝化作用.然而,这些稳定的二维PSC的转换效率仍远远落后于三维钙钛矿电池.在本文中我们通过原位生长的方法将2D EDAPbI4层成功制备在3D FAPbI3层表面。这种合理设计的2D-3D钙钛矿薄膜分层结构可以明显提高电池的效率.另外,由于EDAPbI4层的高抗湿性和抑制迁移, 2D-3D电池器件显示出明显增强的长期稳定性,在200 h内一直保持初始转换效率,甚至在500 h后仍能保持其初始转化效率的90%.     

Co-Solvent Engineering Contributing to Achieve High-Performance Perovskite Solar Cells and Modules Based on Anti-Solvent Free Technology

The pinhole-free and defect-less perovskite film is crucial for achieving high efficiency and stable perovskite solar cells (PSCs), which can be prepared by widely used anti-solvent crystallization strategies. However, the involvement of anti-solvent requires precise control and inevitably brings toxicity in fabrication procedures, which limits its large-scale industrial application. In this work, a facile and effective co-solvent engineering strategy is introduced to obtain high- quality perovskite film while avoiding the usage of anti-solvent. The uniform and compact perovskite polycrystalline films have been fabricated through the addition of co-solvent that owns strong coordination capacity with perovskite components , meanwhile possessing the weaker interaction with main solvent . With those strategies, a champion power conversion efficiency (PCE) of 22% has been achieved with the optimal co-solvent, N-methylpyrrolidone (NMP) and without usage of anti-solvent. Subsequently, PSCs based on NMP show high repeatability and good shelf stability (80% PCE remains after storing in ambient condition for 30 days). Finally, the perovskite solar module (5 × 5 cm) with 7 subcells connects in series yielding champion PCE of 16.54%. This strategy provides a general guidance of co-solvent selection for PSCs based on anti-solvent free technology and promotes commercial application of PSCs.     

Methodologies toward Highly Efficient Perovskite Solar Cells

A perovskite solar cell (PSC) employing an organic–inorganic lead halide perovskite light harvester, seeded in 2009 with power conversion efficiency (PCE) of 3.8% and grown in 2011 with PCE of 6.5% in dye‐sensitized solar cell structure, has received great attention since the breakthrough reports ≈10% efficient solid‐state PCSs demonstrating 500 h stability. Developments of device layout and high‐quality perovskite film eventually lead to a PCE over 22%. As of October 31, 2017, the highest PCE of 22.7% is listed in an efficiency chart provided by NREL. In this Review, the methodologies to obtain highly efficient PSCs are described in detail. In order to achieve a PCE of over 20% reproducibly, key technologies are disclosed from the viewpoint of precursor solution chemistry, processing for defect‐free perovskite films, and passivation of grain boundaries. Understanding chemical species in precursor solution, crystal growth kinetics, light–matter interaction, and controlling defects is expected to give important insights into not only reproducible production of high PCE over 20% but also further enhancement of the PCE of PCSs.     

高效无机CsPbI2Br钙钛矿太阳能电池表面钝化的简便方法

近年来,基于CsPbI2Br的钙钛矿太阳能电池(PVSC)由于能在效率和稳定性之间获得良好平衡而受到越来越多的关注.通过溶液法制备的CsPbI2Br钙钛矿薄膜通常包含各种缺陷,为了获得具有高性能和良好稳定性的钙钛矿太阳能电池,这些缺陷需要被钝化.针对此问题,本文报道了一种简便的缺陷钝化策略,即通过在CsPbI2Br钙钛矿表面旋涂KF溶液来对其进行缺陷钝化.结果表明,沉积的KF大部分位于钙钛矿表面的晶界处,而钙钛矿膜的降解通常始于晶界,因此钝化后的PVSC具有更高的稳定性.稳态和时间分辨光致发光光谱均表明钙钛矿的缺陷被KF显著钝化了.最终,基于KF处理的CsPbI2Br的电池器件能量转换效率(PCE)提高到了15.01%,同时具有较大的开路电压(VOC,1.26 V).与之相比,基于CsPbI2Br的对照器件的PCE仅为14.14%,VOC只有1.18 V.