这个研究项目是由澳大利亚研究理事会通过联动授予南玻太阳能Pty有限公司荆绕支持，承认她的大学，新南威尔士州副校长博士后奖学金。 SEM图像采取通过Jongsung公园使用由新南威尔士大学的电子显微镜单位提供的设备。

1。多晶硅太阳能电池的制作（动画3） <ol><li>硅薄膜沉积<ol class="lalpha"><li>电子束蒸发工具准备烘烤出来〜100°C过夜，以达到&lt;3E-8托基地的压力。预置样本加热到150℃待机温度。 </li><li>使用5x5厘米2（或10×10厘米2）基板硼硅玻璃（肖特Borofloat33），1.1或3.3毫米厚，涂〜80纳米的氮化硅（由PECVD准备从N 2和SiH 4的混合物）制成的基板。 </li><li>基材表面干燥氮气吹，以去除灰尘，并放置到样品架。发泄锁的负载，加载样本，泵负载锁定压力&lt;1E5托，样品传送到主室。启动加热到250°C的设定点约20分钟的泵，当压力达到8E-8 Torr或更低。 </li><li>检查的掺杂源和硅源百叶窗关闭。预置的掺杂源温度为待机温度，即磷源温度在700°C和硼离子源温度在1250°C。启动电子枪，电子枪电流缓慢增加，熔体硅坩埚。 </li><li>时所需的电流达到（从以前的校准：这个电流的电子枪和硅源条件的不同而不同），蒸发所需浓度的P和B掺杂的硅层：35在1E20厘米纳米发射-3的P 2〜3在5E15厘米-3 B的微米吸收100 nm的背表面场（BSF），在4E19厘米-3 B.精确的掺杂浓度达到某些硅沉积速率匹配，测量石英晶体显示器天平（QCM），具有一定的掺杂源的温度，使用SIMS的校准建立了合作关系。 </li><li>蒸发后进行切换关闭加热器，降温〜10分钟的样品。反FER样品负载锁，关闭闸门阀，泄负载锁和卸载的硅薄膜样品。 </li></ol></li><li>硅结晶 如果样品是10×10厘米2，它可以被切割成四个5x5厘米2细胞块大小之前结晶。放置一个粗糙和氮化硅涂层，肖特Robax玻璃（避免粘）持有人（Si薄膜）玻璃上沉积硅薄膜。负载成氮清除烤箱预热至200-300°C。提高温度高达600°C时，3〜5°C /分钟和30小时退火。打开烤箱加热，让烘箱降温自然〜200℃（2〜3小时）起卸前的样品。样品可以有一个凹的形状，由于硅结晶过程中的收缩。这将在下面的快速热加工扁平化。 </li><li>掺杂活化和缺陷退火（RTA） 将样品持有人的结晶膜制成的石墨和LOAD以快速热处理器氩清除。坡道的温度高达600°C时，1°C / S，则高达1000°C在20°C /秒，保持1分钟，然后冷却下来自然〜100°C和卸载。 </li><li>去除表面氧化 立即前到氢化硅薄膜表面氧化过程中形成的结晶和RTA必须拆除，以确保裸露的硅薄膜表面接触到氢。直到硅片表面变为疏水退火样品浸入5％HF溶液（30〜100秒）。与去离子水冲洗和干燥氮气枪。 </li><li>缺陷钝化 样品装入真空室配备了远程氢等离子体源。抽空&lt;1E-4托，加热样品〜620°，打开氩气/氢气的混合物流量（50:150 SCCM），设置压力50-100毫托，开始在3.5千瓦的等离子源微波功率和继续〜10分钟的过程。关闭加热器电源，而mainta伊宁10-15分钟的血浆，直到温度低于350℃之前，血浆和停止气体流量。卸载样品，当温度低于200°C </li><li>细胞金属化 细胞金属化进行了一系列连续的光刻图案，铝薄膜沉积与蚀刻步骤，详细描述在11。最终细胞看起来像在最后一张幻灯片的动画3所示。金属化细胞的特写视图如图1所示。 </li><li>测量EQE的金属化细胞。 </li></ol> 2。制作电浆银纳米粒子（动画4） <ol><li>用干燥的氮气吹金属化的细胞表面，去除灰尘和热蒸发器包含一个W的船装满银颗粒（0.3-0.5克）装入样品。抽空蒸发器室基地的压力2〜3E-5托。方案的QCM对Ag参数：密度10.50Z比0.529。 </li><li>确保样品快门关闭，关闭的W船加热器和增加电流，足够慢，以避免以上8E-5 Torr的压力上升，直到银颗粒融化（如通过观察视图端口）。压力稳定后的电流设定点对应的A / S（校准）0.1-0.2银沉积速率，并打开快门开始沉积过程。 </li><li>监测使用的QCM增长的Ag膜厚度和关闭快门时达到14纳米的厚度。允许在W船约15分钟冷却下来，卸载样品。电影应退火形成纳米颗粒沉积后尽快，尽可能地避免银氧化。 </li><li>新鲜沉积的Ag膜的细胞被置于氮气清除烤箱预热到230 0.1-0.2℃，退火50分钟，然后卸载。注意：由于纳米粒子的表面外观的变化。银纳米粒子的扫描电子显微镜图像是SHOWN 图。 2。 </li><li>测量EQE的细胞与纳米粒子阵列。 </li></ol> 3。制作后反射后方的反射〜300 nm厚的氟化镁（1.38注册机）介质熔覆与商业白色的天花板漆（多乐士）的外衣。 <ol><li>编造后反射之前，必须用黑色记号笔墨水保护细胞接触，这使得从下介质由升空过程中暴露的接触。 </li><li>使用氮气枪吹NP阵列和画接触，清除灰尘的样品。使用温和的氮气压力和运动保健不吹纳米粒子。放入热蒸发器包含一个W船充满氟化镁2件样品。蒸发器泵2〜3E-5 Torr的压力。 氟化镁的QCM参数为：密度3.05和Z比0.637。 </li><li>确保样品shutter被关闭，打开船加热器，慢慢加大电流，以避免过多的压力上升，直到氟化镁熔体通过视图端口。压力稳定后的电流设定点，对应的氟化镁的沉积速率为0.3 nm / s的和打开样品快门。 </li><li>监测使用的QCM沉积厚度和关闭快门时达到300海里。 </li><li>关闭加热器。允许的W船约15分钟冷却下来，卸载样品。注意：在氟化镁2熔覆细胞形态的变化。 </li><li>要取出的细胞接触的油墨面膜浸入丙酮熔覆与介质的细胞。等到开始开裂，抬起上面的油墨介质。保持在丙酮中的细胞，直到所有的墨水与介质和金属接触，充分暴露。从丙酮中取出样品，新鲜的丙酮冲洗和干燥氮气枪。 </li><li>应用层罚款对整个细胞表面的软刷白色油漆（多乐士单涂层的天花板油漆）小心地避免金属接触。油漆层有足够厚，是完全不透明（〜&gt;0.5毫米），所以没有光可以看到在明亮的光源，通过描绘细胞时。让漆干一天。 </li><li>用白色油漆后反射测量细胞EQE。 </li></ol> 4。代表结果通过整合全球标准太阳光谱的EQE曲线（气团1.5）太阳能电池的短路电流计算。无论是电池的电流，其增强由于光捕获依赖于细胞吸收层厚度：目前本身是较高较厚的细胞，但更薄的设备，看到EQE各自的数据和动画5，表1是当前加强高曲线。原来的2微米厚的细胞，没有光捕获，HAVE JSC测量步骤1.7。〜15毫安/厘米2）。后的纳米粒子阵列的制造，的JSC增加了约20毫安/平方厘米 ，其中32％提高。它是略高于由后方的漫反射，只有25-30％的提升效果更好。后加入氟化镁后熔覆细胞与电浆纳米阵列的漫反射，进一步提高司法人员叙用委员会 22.3毫安/厘米2，或45％左右提高。请注意，所有电流为3微米厚的细胞较高，而相对提高到25.7毫安/厘米2略低，42％的光捕获在更薄的设备有较大的影响。 <table border="1"><tbody><tr><td> 电池厚度： </td><td colspan="2"> 2微米 </td><td colspan="2"> 3微米 </td></tr><tr><td></td><td> JSC，毫安/厘米2 </td><td><s<html>阮富仲&gt;％以上</td><td> JSC，毫安/厘米2 </td><td> ％以上 </td></tr><tr><td>原始细胞</td><td> 15.4 </td><td></td><td> 18.1 </td><td></td></tr><tr><td>后漫反射（R）的</td><td> 20.1 </td><td> 30.5 </td><td> 21.5 </td><td> 18.8 </td></tr><tr><td>纳米粒子（NP方案） </td><td> 20.3 </td><td> 31.8 </td><td> 21.9 </td><td> 21.0 </td></tr><tr><td> NP /氟化镁2 / </td><td> 22.3 </td><td> 45.3 </td><td> 25.7 </td><td> 42.0 </td></tr></tbody></table> 表1。电浆电池短路电流和原始细胞相比，其增强。 <img alt="图1" src="/files/ftp_upload/4092/4092fig1.jpg" /> 图1。特写多晶硅薄膜太阳能电池与金属化网格细胞。 / ftp_upload/4092/4092fig2.jpg“/&gt; 图2银纳米粒子的电子显微镜图像扫描的硅表面上。 <img alt="图3" src="/files/ftp_upload/4092/4092fig3.jpg" /> 图3。1电浆薄膜晶体硅太阳能电池（不按比例）的示意图。 <img alt="图4" src="/files/ftp_upload/4092/4092fig4.jpg" /> 图4外部量子效率和短路电流的多晶硅薄膜与漫反射和电浆纳米细胞：虚线黑-原来的2微米厚的细胞，没有光捕获，JSC15.36毫安/厘米2;蓝色-细胞。弥漫油漆反射，JSC 20.08毫安/厘米2;红-与电浆银纳米粒子的细胞，JSC20.31毫安/厘米2;绿色-细胞的纳米粒子， 氟化镁，和弥漫性涂料的反射，JSC </eM&gt;22.32毫安/厘米2。紫色- 3微米厚的细胞（3毫米厚的玻璃），纳米粒子， 氟化镁，和漫反射，JSC 25.7毫安/厘米2（注意蓝色低因无意在AR层和发射层厚度差异）。坚实的黑色- 2微米厚的等离子体增强化学气相沉积法（3毫米厚的玻璃），JSC26.4毫安/厘米2，比较所示的纹理单元准备。 动画1。 <a href="http://www.jove.com/files/ftp_upload/4092/4092animation1.pptx" target="_blank">点击这里查看动画</a> 。 动画2。 <a href="http://www.jove.com/files/ftp_upload/4092/4092animation2.pptx" target="_blank">点击这里查看动画</a> 。 动画3。 <a href="http://www.jove.com/files/ftp_upload/4092/4092animation3.pptx" target="_blank">点击这里查看动画</a>。 动画4。 <a href="http://www.jove.com/files/ftp_upload/4092/4092animation4.pptx" target="_blank">点击这里查看动画</a> 。 动画5。 <a href="http://www.jove.com/files/ftp_upload/4092/4092animation5.pptx" target="_blank">点击这里查看动画</a> 。

<ol>
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没有利益冲突的声明。

蒸发多晶硅太阳能电池及电浆纳米粒子光散射的光捕获的理想合作伙伴。这种细胞是平面的，因此，他们不能依靠光散射表面纹理，也可以很容易地在粗糙的表面形成电浆纳米。细胞有直接接触的硅，这也恰好是最好的最有效的电浆光散射纳米粒子的位置只有一个，后表面。此外，纳米热退火形成的最简单的方法也是最合适的光捕获结果与结晶硅薄膜的光捕获峰之间的700和1000 nm的，最重要的广泛...

<table border="1"><tbody><tr><td> 试剂名称 </td><td> 公司 </td><td> 目录编号 </td><td> 评论 </td></tr><tr><td>银颗粒</td><td> Sigma-Aldrich公司</td><td> 303372 </td><td> 99.99％ </td></tr><tr><td>氟化镁，随机晶体，光学级</td><td> Sigma-Aldrich公司</td><td> 378836 </td><td> &gt; = 99.99％ </td></tr><tr><td>多乐士大衣天花板涂料</td><td>多乐士</td><td></td><td> R&gt; 90％ （500-1100纳米） </td></tr></tbody></table>

polycrystalline silicon thin-film solar cells with plasmonic-enhanced light-trapping

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To compensate for lower light absorption such physically thin devices have to incorporate light-trapping which increases their optical thickness. Light scattering by textured surfaces is a common technique but it cannot be universally applied to all solar cell technologies. Some cells, for example those made of evaporated silicon, are planar as produced and they require an alternative light-trapping means suitable for planar devices. Metal nanoparticles formed on planar silicon cell surface and capable of light scattering due to surface plasmon resonance is an effective approach.
The paper presents a fabrication procedure of evaporated polycrystalline silicon solar cells with plasmonic light-trapping and demonstrates how the cell quantum efficiency improves due to presence of metal nanoparticles.
To fabricate the cells a film consisting of alternative boron and phosphorous doped silicon layers is deposited on glass substrate by electron beam evaporation. An Initially amorphous film is crystallised and electronic defects are mitigated by annealing and hydrogen passivation. Metal grid contacts are applied to the layers of opposite polarity to extract electricity generated by the cell. Typically, such a ~2 &mu;m thick cell has a short-circuit current density (Jsc) of 14-16 mA/cm2, which can be increased up to 17-18 mA/cm2 (~25% higher) after application of a simple diffuse back reflector made of a white paint.
To implement plasmonic light-trapping a silver nanoparticle array is formed on the metallised cell silicon surface. A precursor silver film is deposited on the cell by thermal evaporation and annealed at 23&deg;C to form silver nanoparticles. Nanoparticle size and coverage, which affect plasmonic light-scattering, can be tuned for enhanced cell performance by varying the precursor film thickness and its annealing conditions. An optimised nanoparticle array alone results in cell Jsc enhancement of about 28%, similar to the effect of the diffuse reflector. The photocurrent can be further increased by coating the nanoparticles by a low refractive index dielectric, like MgF2, and applying the diffused reflector. The complete plasmonic cell structure comprises the polycrystalline silicon film, a silver nanoparticle array, a layer of MgF2, and a diffuse reflector. The Jsc for such cell is 21-23 mA/cm2, up to 45% higher than Jsc of the original cell without light-trapping or ~25% higher than Jsc for the cell with the diffuse reflector only.
Introduction
Light-trapping in silicon solar cells is commonly achieved via light scattering at textured interfaces. Scattered light travels through a cell at oblique angles for a longer distance and when such angles exceed the critical angle at the cell interfaces the light is permanently trapped in the cell by total internal reflection (Animation 1: Light-trapping). Although this scheme works well for most solar cells, there are developing technologies where ultra-thin Si layers are produced planar (e.g. layer-transfer technologies and epitaxial c-Si layers) 1 and or when such layers are not compatible with textures substrates (e.g. evaporated silicon) 2. For such originally planar Si layer alternative light trapping approaches, such as diffuse white paint reflector 3, silicon plasma texturing 4 or high refractive index nanoparticle reflector 5 have been suggested.
Metal nanoparticles can effectively scatter incident light into a higher refractive index material, like silicon, due to the surface plasmon resonance effect 6. They also can be easily formed on the planar silicon cell surface thus offering a light-trapping approach alternative to texturing. For a nanoparticle located at the air-silicon interface the scattered light fraction coupled into silicon exceeds 95% and a large faction of that light is scattered at angles above critical providing nearly ideal light-trapping condition (Animation 2: Plasmons on NP). The resonance can be tuned to the wavelength region, which is most important for a particular cell material and design, by varying the nanoparticle average size, surface coverage and local dielectric environment 6,7. Theoretical design principles of plasmonic nanoparticle solar cells have been suggested 8. In practice, Ag nanoparticle array is an ideal light-trapping partner for poly-Si thin-film solar cells because most of these design principle are naturally met. The simplest way of forming nanoparticles by thermal annealing of a thin precursor Ag film results in a random array with a relatively wide size and shape distribution, which is particularly suitable for light-trapping because such an array has a wide resonance peak, covering the wavelength range of 700-900 nm, important for poly-Si solar cell performance. The nanoparticle array can only be located on the rear poly-Si cell surface thus avoiding destructive interference between incident and scattered light which occurs for front-located nanoparticles 9. Moreover, poly-Si thin-film cells do not requires a passivating layer and the flat base-shaped nanoparticles (that naturally result from thermal annealing of a metal film) can be directly placed on silicon further increases plasmonic scattering efficiency due to surface plasmon-polariton resonance 10.
The cell with the plasmonic nanoparticle array as described above can have a photocurrent about 28% higher than the original cell. However, the array still transmits a significant amount of light which escapes through the rear of the cell and does not contribute into the current. This loss can be mitigated by adding a rear reflector to allow catching transmitted light and re-directing it back to the cell. Providing sufficient distance between the reflector and the nanoparticles (a few hundred nanometers) the reflected light will then experience one more plasmonic scattering event while passing through the nanoparticle array on re-entering the cell and the reflector itself can be made diffuse - both effects further facilitating light scattering and hence light-trapping. Importantly, the Ag nanoparticles have to be encapsulated with an inert and low refractive index dielectric, like MgF2 or SiO2, from the rear reflector to avoid mechanical and chemical damage 7. Low refractive index for this cladding layer is required to maintain a high coupling fraction into silicon and larger scattering angles, which are ensured by the high optical contrast between the media on both sides of the nanoparticle, silicon and dielectric 6. The photocurrent of the plasmonic cell with the diffuse rear reflector can be up to 45% higher than the current of the original cell or up to 25% higher than the current of an equivalent cell with the diffuse reflector only.

Watch this Scientific Journal Video about Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping at JoVE.com

Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping

硼，磷掺杂硅结晶，缺陷钝化和金属化层沉积制备多晶硅薄膜太阳能电池玻璃上。电浆光捕获上限〜45％的光增强扩散反射硅电池表面形成银纳米粒子的引入。

多晶硅薄膜太阳能电池电浆增强光捕获

One of major approaches to cheaper solar cells is reducing the amount of semiconductor material used for their fabrication and making cells thinner. To ...

polycrystalline-silicon-thin-film-solar-cells-with-plasmonic-enhanced

Research

JoVE Journal

Engineering

18.7K 次观看.  University of New South Wales. 硼，磷掺杂硅结晶，缺陷钝化和金属化层沉积制备多晶硅薄膜太阳能电池玻璃上。电浆光捕获上限〜45％的光增强扩散反射硅电池表面形成银纳米粒子的引入。

视频: Polycrystalline Silicon Thin-film Solar cells with Plasmonic-enhanced Light-trapping

Nanomoulding of Functional Materials, a Versatile Complementary Pattern Replication Method to Nanoimprinting

We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding combined with layer transfer enables the replication of arbitrary surface patterns from a master structure onto the functional material. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes. In particular we demonstrate the fabrication of patterned transparent zinc oxide electrodes for light trapping applications in solar cells.

We describe a nanomoulding technique which allows low-cost nanoscale patterning of functional materials, materials stacks and full devices. Nanomoulding can be performed on any nanoimprinting setup and can be applied to a wide range of materials and deposition processes.

Nanomoulding功能材料，灵活的互补模式的复制方法，以奈米

We describe a nanomoulding technique which  allows low-cost nanoscale patterning of functional materials, materials stacks  and full devices. Nanomoulding ...

科研

工程学

Synthesis and Characterization of High c-axis ZnO Thin Film by Plasma Enhanced Chemical Vapor Deposition System and its UV Photodetector Application

In this study, zinc oxide (ZnO) thin films with high c-axis (0002) preferential orientation have been successfully and effectively synthesized onto silicon (Si) substrates via different synthesized temperatures by using plasma enhanced chemical vapor deposition (PECVD) system. The effects of different synthesized temperatures on the crystal structure, surface morphologies and optical properties have been investigated. The X-ray diffraction (XRD) patterns indicated that the intensity of (0002) diffraction peak became stronger with increasing synthesized temperature until 400 oC. The diffraction intensity of (0002) peak gradually became weaker accompanying with appearance of (10-10) diffraction peak as the synthesized temperature up to excess of 400 oC. The RT photoluminescence (PL) spectra exhibited a strong near-band-edge (NBE) emission observed at around 375 nm and a negligible deep-level (DL) emission located at around 575 nm under high c-axis ZnO thin films. Field emission scanning electron microscopy (FE-SEM) images revealed the homogeneous surface and with small grain size distribution. The ZnO thin films have also been synthesized onto glass substrates under the same parameters for measuring the transmittance.
For the purpose of ultraviolet (UV) photodetector application, the interdigitated platinum (Pt) thin film (thickness ~100 nm) fabricated via conventional optical lithography process and radio frequency (RF) magnetron sputtering. In order to reach Ohmic contact, the device was annealed in argon circumstances at 450 oC by rapid thermal annealing (RTA) system for 10 min. After the systematic measurements, the current-voltage (I-V) curve of photo and dark current and time-dependent photocurrent response results exhibited a good responsivity and reliability, indicating that the high c-axis ZnO thin film is a suitable sensing layer for UV photodetector application.

We offered a method to directly synthesize high c-axis (0002) ZnO thin film by plasma enhanced chemical vapor deposition. The as-synthesized ZnO thin film combined with Pt interdigitated electrode was used as sensing layer for ultraviolet photodetector, showing a high performance through a combination of its good responsivity and reliability.

合成和高c轴ZnO薄膜等离子体的特性增强化学气相沉积系统及其紫外探测器的应用

In this study, zinc oxide (ZnO) thin films with high c-axis (0002) preferential orientation have been successfully and effectively synthesized onto ...

Integration of Light Trapping Silver Nanostructures in Hydrogenated Microcrystalline Silicon Solar Cells by Transfer Printing

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly known as plasmonic effects, play an important role. Research in this field has, however, been impeded owing to the difficulty of fabricating devices containing the desired functional metal nanostructures. In order to provide a viable strategy to this issue, we herein show a transfer printing-based approach that allows the quick and low-cost integration of designed metal nanostructures with a variety of device architectures, including solar cells. Nanopillar poly(dimethylsiloxane) (PDMS) stamps were fabricated from a commercially available nanohole plastic film as a master mold. On this nanopatterned PDMS stamps, Ag films were deposited, which were then transfer-printed onto block copolymer (binding layer)-coated hydrogenated microcrystalline Si (&#181;c-Si:H) surface to afford ordered Ag nanodisk structures. It was confirmed that the resulting Ag nanodisk-incorporated &#181;c-Si:H solar cells show higher performances compared to a cell without the transfer-printed Ag nanodisks, thanks to plasmonic light trapping effect derived from the Ag nanodisks. Because of the simplicity and versatility, further device application would also be feasible thorough this approach.

A viable transfer printing-based methodology to introduce plasmonic metal nanostructures in solar cells is described. Using nanopillar poly(dimethylsiloxane) stamps, an Ag-based ordered nanodisk array was integrated with standard hydrogenated microcrystalline Si solar cells, which led to improved device performances due to plasmonic light trapping.

灯光诱杀银纳米结构通过转移印花在氢化微晶硅太阳能电池集成

One of the potential applications of metal nanostructures is light trapping in solar cells, where unique optical properties of nanosized metals, commonly ...

Iridium Oxide-reduced Graphene Oxide Nanohybrid Thin Film Modified Screen-printed Electrodes as Disposable Electrochemical Paper Microfluidic pH Sensors

A facile, controllable, inexpensive and green electrochemical synthesis of IrO2-graphene nanohybrid thin films is developed to fabricate an easy-to-use integrated paper microfluidic electrochemical pH sensor for resource-limited settings. Taking advantages from both pH meters and strips, the pH sensing platform is composed of hydrophobic barrier-patterned paper micropad (&#181;PAD) using polydimethylsiloxane (PDMS), screen-printed electrode (SPE) modified with IrO2-graphene films and molded acrylonitrile butadiene styrene (ABS) plastic holder. Repetitive cathodic potential cycling was employed for graphene oxide (GO) reduction which can completely remove electrochemically unstable oxygenated groups and generate a 2D defect-free homogeneous graphene thin film with excellent stability and electronic properties. A uniform and smooth IrO2 film in nanoscale grain size is anodically electrodeposited onto the graphene film, without any observable cracks. The resulting IrO2-RGO electrode showed slightly super-Nernstian responses from pH 2-12 in Britton-Robinson (B-R) buffers with good linearity, small hysteresis, low response time and reproducibility in different buffers, as well as low sensitivities to different interfering ionic species and dissolved oxygen. A simple portable digital pH meter is fabricated, whose signal is measured with a multimeter, using high input-impedance operational amplifier and consumer batteries. The pH values measured with the portable electrochemical paper-microfluidic pH sensors were consistent with those measured using a commercial laboratory pH meter with a glass electrode.

The study demonstrates the growth of iridium oxide-reduced graphene oxide (IrO2-RGO) nanohybrid thin films on irregular and rough screen-printed carbon substrate through a green electrochemical synthesis, and their implementation as a pH sensor with a patterned paper-fluidic platform.

氧化铱还原氧化石墨烯纳米杂化薄膜修饰丝网印刷电极一次性电化学微流控纸pH传感器

A facile, controllable, inexpensive and green electrochemical synthesis of IrO2-graphene nanohybrid thin films is developed to fabricate an easy-to-use ...

Digital Printing of Titanium Dioxide for Dye Sensitized Solar Cells

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less environmentally damaging with lower processing temperatures presenting a viable and low cost alternative to conventional production. This paper further enhances these environmental credentials by evaluating the digital printing and therefore additive production route for these cells. This is achieved here by investigating the formation and performance of a metal oxide photoelectrode using nanoparticle sized titanium dioxide. An ink-jettable material was formulated, characterized and printed with a piezoelectric inkjet head to produce a 2.6 &#181;m thick layer. The resultant printed layer was fabricated into a functioning cell with an active area of 0.25 cm2 and a power conversion efficiency of 3.5%. The binder-free formulation resulted in a reduced processing temperature of 250 &#176;C, compatible with flexible polyamide substrates which are stable up to temperatures of 350 &#730;C. The authors are continuing to develop this process route by investigating inkjet printing of other layers within dye sensitized solar cells.

This paper investigates the suitability of inkjet printing for the manufacturing of dye-sensitized solar cells. A binder-free TiO2 nanoparticle ink was formulated and printed onto a FTO glass substrate. The printed layer was fabricated into a cell with an active area of 0.25 cm2 and an efficiency of 3.5%.

钛白粉用于染料敏化太阳能电池的数码印刷

Silicon solar cell manufacturing is an expensive and high energy consuming process. In contrast, dye sensitized solar cell production is less ...

Recombination Dynamics in Thin-film Photovoltaic Materials via Time-resolved Microwave Conductivity

A method for investigating recombination dynamics of photo-induced charge carriers in thin film semiconductors, specifically in photovoltaic materials such as organo-lead halide perovskites is presented. The perovskite film thickness and absorption coefficient are initially characterized by profilometry and UV-VIS absorption spectroscopy. Calibration of both laser power and cavity sensitivity is described in detail. A protocol for performing Flash-photolysis Time Resolved Microwave Conductivity (TRMC) experiments, a non-contact method of determining the conductivity of a material, is presented. A process for identifying the real and imaginary components of the complex conductivity by performing TRMC as a function of microwave frequency is given. Charge carrier dynamics are determined under different excitation regimes (including both power and wavelength). Techniques for distinguishing between direct and trap-mediated decay processes are presented and discussed. Results are modelled and interpreted with reference to a general kinetic model of photoinduced charge carriers in a semiconductor. The techniques described are applicable to a wide range of optoelectronic materials, including organic and inorganic photovoltaic materials, nanoparticles, and conducting/semiconducting thin films.

A Time Resolved Microwave Conductivity technique for investigating direct and trap-mediated recombination dynamics and determining carrier mobilities of thin film semiconductors is presented here.

通过时间分辨微波电导率重组动力学薄膜光伏材料

A method for investigating recombination dynamics of photo-induced charge carriers in thin film semiconductors, specifically in photovoltaic materials ...

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical properties. The possibility of doping was investigated by adding monovalent cation halides with similar ionic radii to Pb2+, including Cu+, Na+, and Ag+. A shift in the Fermi level and a remarkable decrease of sub-bandgap optical absorption, along with a lower energetic disorder in the perovskite, was achieved. An order-of-magnitude enhancement in the bulk hole mobility and a significant reduction of transport activation energy within an additive-based perovskite device was attained. The confluence of the aforementioned improved properties in the presence of these cations led to an enhancement in the photovoltaic parameters of the perovskite solar cell. An increase of 70 mV in open circuit voltage for AgI and a 2 mA/cm2 improvement in photocurrent density for NaI- and CuBr-based solar cells were achieved compared to the pristine device. Our work paves the way for further improvements in the optoelectronic quality of CH3NH3PbI3 perovskite and subsequent devices. It highlights a new avenue for investigations on the role of dopant impurities in crystallization and controls the electronic defect density in perovskite structures.

Monovalent Cation Doping of CH3NH3PbI3 for Efficient Perovskite Solar Cells

Here, we present a protocol to adjust the properties of solution-processed CH3NH3PbI3 through the incorporation of monovalent cation additives in order to achieve highly efficient perovskite solar cells.

CH的单价阳离子兴奋剂<sub&gt; 3</sub&gt; NH<sub&gt; 3</sub&gt;碘化铅<sub&gt; 3</sub&gt;对钙钛矿型高效太阳能电池

Here, we demonstrate the incorporation of monovalent cation additives into CH3NH3PbI3 perovskite in order to adjust the optical, excitonic, and electrical ...

Electrospinning of Photocatalytic Electrodes for Dye-sensitized Solar Cells

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of electrospun titanium dioxide nanofibers (TiO2-NFs) on top of a blocking layer made of commercially available titanium dioxide nanoparticles (TiO2-NPs). This is achieved by first electrospinning a solution of titanium (IV) butoxide, polyvinylpyrrolidone (PVP), and glacial acetic acid in ethanol to obtain composite PVP/TiO2 nanofibers. These are then calcined at 500 &#176;C to remove the PVP and to obtain pure anatase-phase titania nanofibers. This material is characterized using scanning electron microscopy (SEM) and powder X-ray diffraction (XRD). The photoanode is prepared by first creating a blocking layer through the deposition of a TiO2-NPs/terpineol slurry on a fluorine-doped tin oxide (FTO) glass slide using doctor blading techniques. A subsequent thermal treatment is performed at 500 &#176;C. Then, the light-scattering layer is formed by depositing a TiO2-NFs/terpineol slurry on the same slide, using the same technique, and calcinating again at 500 &#176;C. The performance of the photoanode is tested by fabricating a dye-sensitized solar cell and measuring its efficiency through J-V curves under a range of incident light densities, from 0.25-1 Sun.

The overall goal of this project was to use electrospinning to fabricate a photoanode with improved performance for dye-sensitized solar cells.

染料敏化太阳能电池的光催化电极的电纺丝

This work demonstrates a protocol to fabricate a fiber-based photoanode for dye-sensitized solar cells, consisting of a light-scattering layer made of ...

In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for Cu(In,Ga)Se2 Solar Cells

The levelized cost of electricity (LCOE) of photovoltaic (PV) systems is determined by, among other factors, the PV module reliability. Better prediction of degradation mechanisms and prevention of module field failure can consequently decrease investment risks as well as increase the electricity yield. An improved knowledge level can for these reasons significantly decrease the total costs of PV electricity. 
In order to better understand and minimize the degradation of PV modules, the occurring degradation mechanisms and conditions should be identified. This should preferably happen under combined stresses, since modules in the field are also simultaneously exposed to multiple stress factors. Therefore, two 'Combined Stress test with in situ measurement' setups have been designed and constructed. These setups allow the simultaneous use of humidity, temperature, illumination, and electrical biases as independently controlled stress factors on solar cells and minimodules. The setups also allow real-time monitoring of the electrical properties of these samples. This protocol presents these setups and describes the experimental possibilities. Moreover, results obtained with these setups are also presented: various examples about the influence of both deposition and degradation conditions on the stability of thin film Cu(In,Ga)Se2 (CIGS) as well as Cu2ZnSnSe4 (CZTS) solar cells are described. Results on the temperature dependency of CIGS solar cells are also presented.

In Situ Monitoring of the Accelerated Performance Degradation of Solar Cells and Modules: A Case Study for CuIn,GaSe2 Solar Cells

Two &#39;Combined Stress test with in situ measurement&#39; setups, which allow real-time monitoring of accelerated degradation of solar cells and modules, were designed and constructed. These setups allow the simultaneous use of humidity, temperature, electrical biases, and illumination as independently controlled stress factors. The setups and various experiments executed are presented.

就地太阳能电池和模块加速性能退化的监测: 铜 (in, Ga) Se2太阳能电池的实例研究

The levelized cost of electricity (LCOE) of photovoltaic (PV) systems is determined by, among other factors, the PV module reliability. Better prediction ...

Bulk and Thin Film Synthesis of Compositionally Variant Entropy-stabilized Oxides

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (Cu variant) entropy-stabilized oxides. Phase pure and chemically homogeneous (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (x = 0.20, 0.27, 0.33) and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O (x = 0.11, 0.27) ceramic pellets are synthesized and used in the deposition of ultra-high quality, phase pure, single crystalline thin films of the target stoichiometry. A detailed methodology for the deposition of smooth, chemically homogeneous, entropy-stabilized oxide thin films by pulsed laser deposition on (001)-oriented MgO substrates is described. The phase and crystallinity of bulk and thin film materials are confirmed using X-ray diffraction. Composition and chemical homogeneity are confirmed by X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy. The surface topography of thin films is measured with scanning probe microscopy. The synthesis of high quality, single crystalline, entropy-stabilized oxide thin films enables the study of interface, size, strain, and disorder effects on the properties in this new class of highly disordered oxide materials.

The synthesis of high quality bulk and thin film (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O and (Mg0.25(1-x)Co0.25(1-x)Ni0.25(1-x)CuxZn0.25(1-x))O entropy-stabilized oxides is presented.

组分变熵稳定氧化物的体积和薄膜合成

Here, we present a procedure for the synthesis of bulk and thin film multicomponent (Mg0.25(1-x)CoxNi0.25(1-x)Cu0.25(1-x)Zn0.25(1-x))O (Co variant) and ...