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991.
Salma Zouhair;Charlotte Clegg;Irina Valitova;Samuel March;Javith Mohammed Jailani;Vincenzo Pecunia; 《Solar RRL》2024,8(6):2300929
Carbon electrodes have gained significant attention as a cost-effective, sustainable, stable, and scalable replacement for metal electrodes in perovskite solar cells (PSCs). However, traditional carbon-electrode-based PSCs (C-PSCs) lack a hole-selective layer (HSL) due to their incompatibility with the most effective organic HSLs employed in the PSC literature. In turn, the absence of an HSL has been identified as one of the main factors hindering the performance of C-PSCs. Consequently, numerous studies have recognized the pivotal significance of the region between the perovskite absorber and the carbon electrode in C-PSCs, proposing various interfacial engineering strategies to improve the performance of these solar cells. Given the rapid evolution of this field, an up-to-date and comprehensive review of C-PSCs is in order. Key areas of focus of this review include the shift from high-temperature to low-temperature carbon electrodes, strategies to improve energetic alignment at the interface, novel approaches such as hole-selective bilayers, and alternative carbon deposition methods to reduce solvent damage. Additionally, this review presents a comprehensive meta-analysis—the first of its kind in the C-PSC literature—to assess how various interfacial modifications impact critical C-PSC performance metrics, offering valuable insights for future advancements in the field. 相似文献
992.
Xibiao Li;Baichen Ye;Lan Jiang;Xiaowei Li;Yang Zhao;Liangti Qu;Peng Yi;Taoyong Li;Min Li;Luqi Li;Andong Wang;Xiangyu Zhang;Jiafang Li; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(45):2400569
Solar thermal utilization has broad applications in a variety of fields. Currently, maximizing the photo-thermal conversion efficiency remains a research hotspot in this field. The exquisite plant structures in nature have greatly inspired human structural design across many domains. In this work, inspired by the photosynthesis of helical grass, a HM type solar absorber made in graphene-based composite sheets is used for solar thermal conversion. The unique design promoted more effective solar energy into thermal energy through multiple reflections and scattering of solar photons. Notably, the Helical Micropillar (HM) is fabricated using a one-step projection 3D printing process based on a special 3D helical beam. As a result, the solar absorber's absorbance value can reach 0.83 in the 400–2500 nm range, and the surface temperature increased by ≈128.3% relative to the original temperature. The temperature rise rate of the solar absorber reached 22.4 °C min−1, demonstrating the significant potential of the HM in practical applications of solar thermal energy collection and utilization. 相似文献
993.
Erin M. Tonita;Christopher E. Valdivia;Annie C. J. Russell;Michael Martinez-Szewczyk;Mariana I. Bertoni;Karin Hinzer; 《Progress in Photovoltaics: Research and Applications》2024,32(7):468-480
We provide a comprehensive analysis of the effect of spectral albedo on photovoltaic (PV) module measurements and system model predictions. We demonstrate how to account for albedo in indoor bifacial device measurements by adjusting the applied irradiance using the scaled rear irradiance method, exemplified on fabricated silicon heterojunction (SHJ) modules. System model performance is studied using a detailed 3D finite-element model, DUET, for fixed-tilt and horizontal single-axis tracked (SAT) arrays between 15 and 75°N. Spectral effects cause variations in measured SHJ module short-circuit current up to 2% and efficiency variation up to 0.3% abs. We further demonstrate that rear-side spectral mismatch factors (SMMs) resulting from including or omitting spectral albedo in PV system modeling vary between ±13%, while total (front+rear) SMMs vary up to 3%, depending on the deployment configuration and latitude. SAT array SMMs are weakly correlated with latitude, while fixed-tilt array SMMs increase with latitude, driven by an increasing proportion of ground-reflected light on the front-side of modules. Ground-reflections can constitute between 2% and 32% of total incident module irradiance, with notably high (>10%) contributions for fixed-tilt arrays at high latitude. Effects of spectral albedo are most significant for: (1) fixed-tilt deployments at high latitudes, (2) wide bandgap technologies such as perovskite and cadmium telluride cells, (3) albedos which vary steeply over the technology's absorption range, and (4) high albedo ground covers. Overall, we demonstrate that omitting spectral albedo effects can result in PV measurement and system-level modeling uncertainties on the order of several percent in these cases. 相似文献
994.
Martin A. Green;Ewan D. Dunlop;Masahiro Yoshita;Nikos Kopidakis;Karsten Bothe;Gerald Siefer;Xiaojing Hao; 《Progress in Photovoltaics: Research and Applications》2024,32(1):3-13
Consolidated tables showing an extensive listing of the highest independently confirmed efficiencies for solar cells and modules are presented. Guidelines for inclusion of results into these tables are outlined and new entries since July 2023 are reviewed. 相似文献
995.
Rui Wang;Jong-Min Lee; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(36):2401546
The design of high-energy facets in electrocatalysts has attracted significant attention due to their potential to enhance electrocatalytic activity. In this review, the significance of high-energy facets in various electrochemical reactions are highlighted, including oxygen reduction reaction (ORR), oxygen evolution reaction (OER), hydrogen evolution reaction (HER), nitrogen reduction reaction (NRR), and carbon dioxide reduction reaction (CRR). Their importance in various electrochemical reactions and present strategies for constructing high-energy facets are discussed, including alloying, heterostructure formation, selective etching, capping agents, and coupling with substrates. These strategies enable control over crystallographic orientation and surface morphology, fine-tuning electrocatalytic properties. This study also addresses future directions and challenges, emphasizing the need to better understand fundamental mechanisms. Overall, high-energy facets offer exciting opportunities for advancing electrocatalysis. 相似文献
996.
规范认为T形和十字形圆钢管节点的平面内抗弯承载力相同,但两类节点的受力特性不同。为了全面对比T形节点和十字形节点的平面内受弯性能,进行了6个节点(4个十字形和2个T形)平面内往复弯矩加载试验,并进行了受力机理分析和有限元分析,其中十字形节点进行了两侧支管同向受弯、反向受弯两种加载模式。结果表明：所有节点均为节点域主管管壁延性撕裂破坏,表现出较好的抗震性能;增加支主管直径比β能明显提高节点的抗弯承载力、延性、耗能能力;T形节点的抗弯承载力高于十字形节点,但延性不如十字形节点,T形节点的耗能能力介于十字形节点在两种加载模式下的耗能能力之间;对比反向受弯加载,同向受弯加载对β较小(接近及小于0.7)十字形节点的性能(耗能、延性和承载力)不利,但对β较大(接近及大于0.9)十字形节点的性能有利。 相似文献
997.
本文综述了上转换复合材料在光催化中的应用研究进展。由于传统光催化半导体材料对太阳辐射利用率低,限制了其在环境治理和能源转化方面的实际应用。上转换复合材料可以将低能量辐射转化为高能量发射,提高光催化剂对红外-可见光的响应性,从而提高太阳光利用率。本文首先阐述了光催化反应的基本原理和应用前景,接着重点分析了稀土、量子点、三重态-三重态湮灭等3种类型的上转换复合光催化剂的制备方法、性能特点和优缺点,并举例介绍了利用贵金属或合金增强上转换效果和电荷分离效率的优化策略。本文旨在为光催化研究提供新思路和参考,促进上转换复合材料在光催化领域中的应用和发展。 相似文献
998.
Minxing Yan;Lingfeng Zhou;Lixiang Wang;Guangjie Luo;Li Xu;Deren Yang;Yanjun Fang; 《Small (Weinheim an der Bergstrasse, Germany)》2024,20(18):2309233
Perovskite light-emitting diodes (PeLEDs) have shown incalculable application potential in the fields of next-generation displays and light communication owing to the rapidly increased external quantum efficiencies (EQEs). However, most PeLEDs obtain a maximum EQE at small current density (J) region and suffer from severe efficiency roll-off in different extents. Herein, it is demonstrated that the dopant with large dipole moment like KBF4 facilitates the effective dielectric regulation of perovskite emissive layer. The increased dielectric constant lowers the exciton binding energy and suppresses the Auger recombination of the 2D/3D segregated perovskite structure, which improves the photoluminescence quantum yield remarkably at an excitation intensity up to 103 mW cm−2. Accordingly, the top-emission PeLED that delivers a high maximum EQE above 20% is fabricated and can retain EQE > 10% at an extremely high J of 708 mA cm−2. These results represent one of the most efficient top-emission PeLEDs with ultra-low efficiency roll-off, which provide a viable methodology for tuning the dielectric response of perovskite films for improved high radiance performance of perovskite electroluminescence devices. 相似文献
999.
在非化石能源迅速发展和能源保供安全的背景下,如何提高煤炭企业的经济效益已成为重要的关注点。以国家能源集团一体化运营模式下包头能源公司煤炭产业为例,建立经营利润测算、外购煤利润测算和自产煤利润测算3个模型,并将模型内嵌到经营测算系统中。经营测算系统对数据进行综合测算分析,为企业决策分析提供科学依据和重要参考,同时为生产计划综合调整提供保障,从而有效地保证煤炭供应和供应安全。使用该系统对李家壕煤矿和万利一矿进行经济测算,其结果符合煤矿生产成本和利润等方面的实际情况,在保障能源安全的前提下有效地提高了煤矿的生产经营效益。
相似文献1000.
为研究粒径对煤自燃特性的影响,以刘庄矿8煤为研究对象,开展不同粒径煤样的程序升温实验,构建煤样耗氧速率、气体产物生成速率与温度及粒径的关系模型。研究结果表明,煤样耗氧速率、气体产物生成速率随着煤样粒径的增大先线性减小后迅速下降,且温度越高,粒径对煤自燃特性参数的影响越大;当煤样粒径从0.125 mm增大至0.425 mm时,煤样的临界温度从80 ℃降低至60 ℃,干裂温度从120 ℃降低至110 ℃;在临界温度前煤的活化能随着粒径增大而逐渐增大,但混合粒径范围越大,活化能相应减小,而在干裂温度后煤的活化能变化规律与此相反;在一定粒径及温度范围内,煤样耗氧速率、气体产物生成速率随煤样粒径及温度的变化规律可用2D高斯函数分布来描述。
相似文献