Nanobowl arrays endow perovskite solar cells with iridescent colors by Staff Writers Beijing, China (SPX) Jul 11, 2019
With the maturing of the perovskite solar cells (PSCs) technology, it is highly desirable to develop colorful solar cells to satisfy the requirements of aesthetic purposes in applications including building integrated photovoltaics and wearable electronics. The broad optical absorption and the large absorption coefficient of perovskites normally lead to high-efficiency cells with dark-brown colors. Till now, two representative approaches have been used to achieve colorful PSCs: (1) bandgap engineering and (2) structural colors. The former approach usually leads to considerably reduced power conversion efficiency (PCE) values (typically less than 13%) owing to diminished optical absorption associated with the enlarged bandgap. The latter approach takes advantage of engineered optical properties arising from patterned structures, enabling the generation of structural colors that are bright and dazzling. Despite the great efforts devoted to the colorful PSCs with respectable efficiencies, it remains a challenge to realize high-efficiency, colorful PSCs through deliberate structural design. 2D patterned nanobowl arrays with a remarkable photonic structure have been previously employed an electron transport layer (ETL) to fabricate efficient PSCs, but the obtained PSCs showed only dark or dark-brown colors, which could be related to the full filling of the nanobowls by the perovskite overlayer. Recently, Limin Qi's research group in Peking University have developed a novel strategy to prepare colorful PSCs by delicate deposition of a uniform perovskite thin layer into arrayed NBs acting as a structured ETL without jeopardizing their photonic properties. They succeeded in using TiO2 NB arrays as a photonic ETL to integrate with a uniform thin overlayer of CH3NH3PbI3, achieving high-efficiency colorful perovskite solar cells. A new crystalline precursor film based on lead acetate was prepared through a Lewis acid base adduct approach, which allowed for uniform deposition of the precursor thin film onto the inner walls of the TiO2 NBs and subsequent formation of a uniform overlayer of high-quality perovskite crystals. The perovskite solar cells fabricated using the nanobowl arrays inherited the photonic properties of the periodic structures, showing angle-dependent vivid colors under light illumination (Figure 1). These colorful PSCs exhibited a remarkable photovoltaic performance with a champion efficiency up to 16.94% and an average efficiency of 15.47%, which are higher than those for all the colorful PSCs reported so far. It is expected that the performance of the colorful PSCs based on the nanobowl arrays could be further improved by delicately manipulating the patterned nanoarray structure and optimizing the deposition processes of the perovskite films. This work may open a new avenue toward high-efficiency colorful perovskite solar cells with promising applications including building integrated photovoltaics.
Research Report: "High-efficiency colorful perovskite solar cells using TiO2 nanobowl arrays as a structured electron transport layer"
Getting more heat out of sunlight Boston MA (SPX) Jul 08, 2019 A newly developed material that is so transparent you can barely see it could unlock many new uses for solar heat. It generates much higher temperatures than conventional solar collectors do - enough to be used for home heating or for industrial processes that require heat of more than 200 degrees Celsius (392 degrees Fahrenheit). The key to the process is a new kind of aerogel, a lightweight material that consists mostly of air, with a structure made of silica (which is also used to make glass). ... read more
|
|
The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us. |