• Thin, lightweight layer provides radiati

    From ScienceDaily@1:317/3 to All on Tue Jan 31 21:30:22 2023
    Thin, lightweight layer provides radiation barrier for perovskites in
    space, protection from elements on Earth

    Date:
    January 31, 2023
    Source:
    DOE/National Renewable Energy Laboratory
    Summary:
    An ultrathin protective coating proves sufficient to protect
    a perovskite solar cell from the harmful effects of space and
    harden it against environmental factors on Earth, according to
    newly published research.


    Facebook Twitter Pinterest LinkedIN Email
    FULL STORY ==========================================================================
    An ultrathin protective coating proves sufficient to protect a perovskite
    solar cell from the harmful effects of space and harden it against environmental factors on Earth, according to newly published research
    from the U.S.

    Department of Energy's National Renewable Energy Laboratory (NREL).


    ========================================================================== Funded by the U.S. Department of Defense's Operational Energy Capability Improvement Fund (OECIF), the NREL research was done for the Air Force
    Research Laboratory (AFRL) to develop low-cost innovative energy sources
    for powering the armed forces worldwide.

    The research is the latest effort to determine the effectiveness of
    perovskites for use in space applications, where it would be exposed to protons, alpha particles, atomic oxygen, and other stressors. The ability
    to use perovskites to generate power in space is enticing because they
    offer a lower-cost and lightweight option to other technologies with the potential for achieving efficiencies similar to those of current space
    PV technologies.

    Just as on Earth, perovskite solar cells need to have suitable durability.

    However, the environment in space is significantly different. While the
    biggest challenges on Earth are related to weather, in space perovskites
    must address the problems that come from radiation bombardment and
    extreme temperature swings. Perovskites show signs of better tolerance
    to radiation than many other solar cells, but plenty of testing remains
    to be conducted.

    Researchers last year ran simulations to demonstrate how exposure
    to radiation in space would affect perovskites. They determined the next-generation technology would work in space but pointed out the need
    to encapsulate the cell in some way to provide added protection.

    In the follow-up research, Ahmad Kirmani, lead author of the latest
    Nature Energy paper, said simulations demonstrated a micron-thick layer
    of silicon oxide would preserve the efficiency and increase the lifetime
    of perovskite solar cells in space. As a comparison, the micron-thick
    layer is about 100 times thinner than a typical human hair.

    Kirmani said the silicon oxide layer could reduce the weight of
    conventional radiation barriers used for other solar cells by more than
    99% and serves as a first step toward designing lightweight and low-cost packaging for perovskites.

    High-energy protons travel through perovskite solar cells without causing
    much harm. Low-energy protons, however, are more abundant in space and
    wreak more havoc on perovskite cells by knocking atoms out of place
    and causing efficiency levels to steadily decline. The lower energy
    protons interact with matter much more readily and the addition of the
    silicon oxide layer protected the perovskite from damage even from the low-energy protons.

    "We thought it would be impossible for the silicon oxide to provide
    protection against fully penetrating long-range particles such as the high-energy protons and alpha particles," Kirmani said. "However, the
    oxide layer turned out to be a surprisingly good barrier against those as well." The results are detailed in the paper "Metal oxide barrier layers
    for terrestrial and space perovskite photovoltaics." The co-authors are
    David Ostrowski, Kaitlyn VanSant, Rosemary Bramante, Karen Heinselman,
    Jinhui Tong, Bart Stevens, William Nemeth, Kai Zhu, and Joseph Luther,
    from NREL; and several key collaborators who work with the team from
    the University of North Texas and the University of Oklahoma. VanSant
    holds the unique position of being a postdoctoral researcher at NASA
    who conducts research at NREL.

    Exposure to a stream of low-energy protons caused unprotected perovskite
    solar cells to lose only about 15% of their initial efficiency, the
    researchers found. A larger concentration of particles destroyed the
    cells, while the protected perovskites demonstrated what the scientists described as "a remarkable resilience." With the simple barrier, the
    cells showed no damage.

    In addition to making the cells more resilient in space, the researchers
    also tested how the barrier could provide benefit in more conventional applications.

    They then exposed the perovskite solar cells to an uncontrolled
    moisture and temperature environment for several days to mimic storage conditions. The protected cells retained their initial 19% efficiency,
    while the unprotected cells showed significant degradation, from 19.4%
    to 10.8%. The oxide layer also provided protection when other perovskite compositions typically more sensitive to moisture were exposed to water.

    Further, the perovskite solar cells were subjected to a test chamber where
    they were bombarded with ultraviolet photons similar to the environment
    at low-Earth orbit. The photons interacted with oxygen to create atomic
    oxygen. The unprotected cells were destroyed after eight minutes. The
    protected cells retained their initial efficiency after 20 minutes and
    only had a slight drop after 30 minutes.

    The simulations and experiments revealed that by reducing the damage
    from radiation, the lifetime of the protected solar cells used in Earth's orbits and deep space would be increased from months to years.

    "Power conversion efficiency and operational stability of perovskite
    solar cells have been the two primary focus areas for the community so
    far," he said.

    "We have made a lot of progress and I think we have come far to the
    point that we might be pretty close to hitting those targets needed
    for industrialization.

    However, to really enable this market entry, packaging is the next
    target." Because perovskite solar cells can be deposited onto a flexible substrate, the emerging technology, coupled with the protective layer
    of silicon oxide, allows its use for various terrestrial applications
    such as powering drones.

    NREL is the U.S. Department of Energy's primary national laboratory for renewable energy and energy efficiency research and development. NREL
    is operated for DOE by the Alliance for Sustainable Energy LLC.

    * RELATED_TOPICS
    o Space_&_Time
    # Sun # Solar_Flare # Northern_Lights
    o Matter_&_Energy
    # Solar_Energy # Graphene # Energy_Technology
    o Earth_&_Climate
    # Energy_and_the_Environment # Geomagnetic_Storms #
    Renewable_Energy
    * RELATED_TERMS
    o Solar_cell o Greenhouse_effect o
    Environmental_impact_assessment o Earth's_atmosphere o
    History_of_Earth o Geomagnetic_storm o Planet o Solar_eclipse

    ========================================================================== Story Source: Materials provided by
    DOE/National_Renewable_Energy_Laboratory. Note: Content may be edited
    for style and length.


    ========================================================================== Journal Reference:
    1. Ahmad R. Kirmani, David P. Ostrowski, Kaitlyn T. VanSant, Todd
    A. Byers,
    Rosemary C. Bramante, Karen N. Heinselman, Jinhui Tong, Bart
    Stevens, William Nemeth, Kai Zhu, Ian R. Sellers, Bibhudutta Rout,
    Joseph M.

    Luther. Metal oxide barrier layers for terrestrial and
    space perovskite photovoltaics. Nature Energy, 2023; DOI:
    10.1038/s41560-022-01189-1 ==========================================================================

    Link to news story: https://www.sciencedaily.com/releases/2023/01/230131183137.htm

    --- up 48 weeks, 1 day, 10 hours, 50 minutes
    * Origin: -=> Castle Rock BBS <=- Now Husky HPT Powered! (1:317/3)