Enhancement of light‐harvesting efficiency (LHE) in the red/near‐IR (NIR) region (600–1000 nm) of the solar spectrum is a challenge to improvement of the photovoltaic performances of dye‐sensitized ...solar cells (DSSCs). Therefore, design and development of effective red/NIR photosensitizers are currently a hot topic in DSSCs. BODIPY dyes can offer magnificent characteristics such as sharp and moderately strong absorption, large quantum yields, long excited state lifetimes, good solubility and easy chromatographic separation. From this perspective, recent progress in BODIPY‐sensitized solar cells is reviewed.
Harnessing maximum light from the solar spectrum is the key to improve photovoltaic performance of solar cells. Possessing outstanding photophysical properties and flexibility in structural modification, BODIPY dyes have emerged as potential sensitizers for Dye‐Sensitized Solar Cells (DSSCs).
In recent times, Supply chains are required to undergo the structural changes in order to adapt to the positive events such as Industry 4.0 and negative events such as natural and man-made disasters. ...Both positive and negative events tend to cause disruptions and affect business operations continuity. Supplier selection, being the critical and foremost activity must ensure that selected suppliers are capable of supporting the organizations against disruptions caused by these events. Hence, supplier selection and order allocation must be restructured considering the dynamics of Industry 4.0 and disaster events to ensure undisrupted flow of materials across supply chain. The paper proposes a multi stage hybrid model for integrated supplier segmentation, selection and order allocation considering risks and disruptions. The suppliers are then evaluated based on set of criteria suitable in Industry 4.0 environment using Data Envelopment Analysis (DEA) and are further prioritized using Fuzzy Analytical Hierarchical Process and Technique for Order of Preference by Similarity to Ideal Solution (FAHP-TOPSIS). The risk associated with each supplier is computed. The paper also proposes a Mixed Integer Program (MIP) as to optimize multi-period, multi item order allocation to suppliers in such a way that overall cost and risk of disruption is simultaneously minimized. In event of any disruption either from supply or demand side, the multi-stage hybrid model tends to reduce its economic impact by allocating emergency orders, thus, ensuring business operations continuity. The proposed multi-stage hybrid model is illustrated using a case of an automobile company.
Non-fullerene organic solar cells employing small molecule acceptors have recently crossed the PCE of 17% through the design and synthesis of efficient acceptor materials. One of the greatest ...advantages of non-fullerene acceptors (NFAs) is the tunability of the absorption spectrum, frontier molecular orbital (FMO) energy levels and solubility
via
molecular engineering. Electron deficient chromophoric groups play an important role in the synthesis of efficient non-fullerene acceptors. End groups enhance the absorption, electron acceptor properties and overall performance of a molecule as an acceptor after attaching with a π-conjugated backbone. In this review, a number of NFAs are highlighted focusing on the effect of terminal chromophoric groups on the overall performance of organic photovoltaic devices.
Non-fullerene organic solar cells employing small molecule acceptors have recently crossed the PCE of 17% through the design and synthesis of efficient acceptor materials.
Organic molecules can absorb or emit light in UV, visible and infra‐red (IR) region of solar radiation. Fifty percent of energy of solar radiation lies in the IR region of solar spectrum and extended ...π‐conjugated molecules containing low optical band gap can absorb NIR radiations. Recently IR molecules have grabbed the attention of synthetic chemists. Although only few molecules have been reported so far such as derivative of BODIPY, naphthalimide, porphyrins, perylene, BBT etc., they have shown highest absorbing capacity towards greater than 1100 nm. These compounds have potential applications in different fields, such as for biomedical and optoelectronic applications. In this review, we present different classes of light‐harvesters with harvesting range above 1000 nm.
Sun light is a part of the electromagnetic radiation given off by the sun. Organic molecules can absorb and emit light in different regions of solar radiation. Almost 50 % of solar energy lies in the IR region of solar radiation. Low band gap π‐conjugated materials can absorb NIR radiation. NIR absorbing molecules have potential application in biomedical and photoelectronic applications.
Recent advances in flexible perovskite solar cells Susrutha, B; Giribabu, Lingamallu; Singh, Surya Prakash
Chemical communications (Cambridge, England),
01/2015, Letnik:
51, Številka:
79
Journal Article
Recenzirano
Flexible and low-weight thin-film perovskite solar cells have attracted considerable attention for developing large-area, roll-to-roll and differently shaped photovoltaics with improved power ...conversion efficiencies. In this review, we describe how researchers have adopted different approaches to enhance the device performance of the flexible perovskite solar cells to compete with rigid substrates with tailored electron/hole transport materials and flexible substrates.
Flexible thin-film photovoltaics facilitate the implementation of solar devices into portable, reduced dimension, and roll-to-roll modules. In this review, we describe recent developments in the fabrication of flexible perovskite solar cells that are low cost and highly efficient and can be used for the fabrication of large-area and lightweight solar cell devices.
Purpose
The purpose of this paper is to present a methodology to analyze the risks present in perishable food supply chain and to determine the most effective risk mitigation strategies. It is ...achieved by understanding the dynamics between various risks in perishable food supply chain and modeling them using interpretive structural modeling (ISM).
Design/methodology/approach
Four categories and 17 types of risk are established from literature and conducting brainstorming sessions with managers/engineers in Indian dairy firms. A methodology is proposed using ISM, risk priority number and risk mitigation number to prioritize risk mitigation strategy decisions for the dairy industry.
Findings
For a perishable food supply chain, risk positioned at lower levels (levels 1 or 2) in the hierarchy should be targeted first, while formulating mitigation strategies. To investigate further, risk- enabling factors which are identified for an Indian dairy firm for these levels 1 and 2 risks and mitigation strategy prioritization show that supplier side risks are more dominant followed by market risks and process risks.
Research limitations/implications
This proposed methodology has not been statistically validated or empirically tested, and factors taken are in the Indian context, but the authors believe that the study is highly relevant to other markets as well because the ISM-based analysis is for generic perishable food supply chain environment.
Practical implications
This study provides a useful approach to managers/decision makers to identify, analyze and prioritize risk in the supply chain. It also provides insights into the mutual relationships of supply chain risks which would help them to focus on the effective risk mitigation strategies formulation. The study provides the insights to benchmark and risk management in the dairy industry environment with priority considerations.
Originality/value
This paper provides an integrated approach to identifying, quantify, analyze, evaluate and mitigate the risks of perishable food (in the dairy environment) in the Indian context.
Closed loop supply chain network design (CL-SCND) is a critical economic and environmental activity. The closing of the loop to handle return, uncertainty in business environment, various supply ...chain risks, impact network design processes and performance of the firm in the long term. Thus, it is important to design robust and reliable supply chain structures and obtain network configurations which can always outperform the other configurations under the worst cases of risks and uncertainty. A generic closed-loop supply chain network based on mixed integer programming formulation is proposed with direct shipping to the customer from manufacturing plants as well as shipping through distribution centers under supply risks, transportation risk and uncertain demand using a robust optimization (RO) approach. A large number of numerical tests are carried out to test the performance of the model by considering a total of four levels of uncertainty for four different network structures types. The results of the tests confirm that the risk and uncertainty based integrated supply chain network models are more efficient (cost effective) than the other set of network configurations which treats the supply chain risks and uncertainty post-ante. To demonstrate the applicability of the proposed model, the case of an Indian e-commerce firm which wants to redesign its supply chain structure is presented. The results of case study show that the topology obtained from integrated treatment of risk and uncertainty called as RORU model, outperform other supply chain networks on various network performance indicators such as supply chain costs, the number of facilities open or close and the amount of products flowing through supply chain echelon. Thus, RO based mathematical modeling to address risks and its applicability for SCND for close loop supply chain is proposed, demonstrated and applied in practical cases.
This review gives an overview of the design and development of perovskite solar cells with a main focus on hole transporting materials (HTMs). The recent advances in metal halide perovskite solar ...cells surprised the traditional photovoltaic community. A key advance was subsequently made by replacing liquid electrolytes with solid state HTMs like spiro-OMeTAD, which not only improve power conversion efficiency but also enhance the cell stability. As a result, many research groups, including our group, have become involved in the synthesis of new HTMs to optimize the photovoltaic properties of perovskite solar cells (PSCs).
The hole transporting materials in perovskite solar cells have received significant attention in recent years as a promising materials capable of developing high performance photovoltaic devices at low cost.
