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Abstract The combined effects of compact TiO2(c‐TiO2) electron‐transport layer (ETL) are investigated without and with mesoscopic TiO2(m‐TiO2) on top, and without and with an iodine‐terminated silane self‐assembled monolayer (SAM), on the mechanical behavior, opto–electronic properties, photovoltaic (PV) performance, and operational‐stability of solar cells based on metal‐halide perovskites (MHPs). The interfacial toughness increases almost threefold in going from c‐TiO2without SAM to m‐TiO2with SAM. This is attributed to the synergistic effect of the m‐TiO2/MHP nanocomposite at the interface and the enhanced adhesion afforded by the iodine‐terminated silane SAM. The combination of m‐TiO2and SAM also offers a significant beneficial effect on the photocarriers extraction at the ETL/MHP interface, resulting in perovskite solar cells (PSCs) with power‐conversion efficiency (PCE) of over 24% and 20% for 0.1 and 1 cm2active areas, respectively. These PSCs also have exceptionally long operational‐stability lives: extrapolatedT80 (duration at 80% initial PCE retained) is ≈18 000 and 10 000 h for 0.1 and 1 cm2active areas, respectively.Postmortemcharacterization and analyses of the operational‐stability‐tested PSCs are performed to elucidate the possible mechanisms responsible for the long operational‐stability.
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Electronic modulation of metal-support interactions improves polypropylene hydrogenolysis over ruthenium catalysts
Abstract Ruthenium (Ru) is the one of the most promising catalysts for polyolefin hydrogenolysis. Its performance varies widely with the support, but the reasons remain unknown. Here, we introduce a simple synthetic strategy (using ammonia as a modulator) to tune metal-support interactions and apply it to Ru deposited on titania (TiO2). We demonstrate that combining deuterium nuclear magnetic resonance spectroscopy with temperature variation and density functional theory can reveal the complex nature, binding strength, and H amount. H2activation occurs heterolytically, leading to a hydride on Ru, an H+on the nearest oxygen, and a partially positively charged Ru. This leads to partial reduction of TiO2and high coverages of H for spillover, showcasing a threefold increase in hydrogenolysis rates. This result points to the key role of the surface hydrogen coverage in improving hydrogenolysis catalyst performance.
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- Award ID(s):
- 1720530
- PAR ID:
- 10370565
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 13
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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