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To address the critical issues in solar energy, the current research has focused on developing advanced solar harvesting materials that are low cost, lightweight, and environmentally friendly. Among many organic photovoltaics (PVs), the porphyrin compounds exhibit unique structural features that are responsible for strong ultraviolet (UV) and near infrared absorptions and high average visible transmittance, making them ideal candidates for solar-based energy applications. The porphyrin compounds have also been found to exhibit strong photothermal (PT) effects and recently applied for optical thermal insulation of building skins. These structural and optical properties of the porphyrin compounds enable them to function as a PT or a PV device upon sufficient solar harvesting. It is possible to develop a transparent porphyrin thin film with PT- and PV-dual-modality for converting sunlight to either electricity or thermal energy, which can be altered depending on energy consumption needs. A building skin can be engineered into an active device with the PT- and PV-dual modality for large-scale energy harvesting, saving, and generation. This review provides the current experimental results on the PT and PV properties of the porphyrin compounds such as chlorophyll and chlorophyllin. Their PT and PV mechanisms are discussed in correlations to their electronic structures. Also discussed are the synthesis routes, thin film deposition, and potential energy applications of the porphyrin compounds.
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Advanced Nanowood Materials for the Water–Energy Nexus
Wood materials are being reinvented to carry superior properties for a variety of new applications. Cutting‐edge nanomanufacturing transforms traditional bulky and low‐value woods into advanced materials that have desired structures, durability, and functions to replace nonrenewable plastics, polymers, and metals. Here, a first prospect report on how novel nanowood materials have been developed and applied in water and associated industries is provided, wherein their unique features and promises are discussed. First, the unique hierarchical structure and associated properties of the material are introduced, and then how such features can be harnessed and modified by either bottom‐up or top‐down manufacturing to enable different functions for water filtration, chemical adsorption and catalysis, energy and resource recovery, as well as energy‐efficient desalination and environmental cleanup are discussed. The study recognizes that this is a nascent but very promising field; therefore, insights are offered to encourage more research and development. Trees harness solar energy and CO2 and provide abundant carbon‐negative materials. Once harvested and utilized, it is believed that advanced wood materials will play a vital role in enabling a circular water economy.
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- Award ID(s):
- 1834724
- PAR ID:
- 10196355
- Date Published:
- Journal Name:
- Advanced Materials
- ISSN:
- 0935-9648
- Page Range / eLocation ID:
- 2001240
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/adma.202001240
