Publications by authors named "R Vajtai"

The 2D Ruddlesden-Popper (RP) perovskites CsPbICl (Pb-based, = 1) and CsSnICl (Sn-based, = 1) stand out as unique and rare instances of entirely inorganic constituents within the more expansive category of organic/inorganic 2D perovskites. These materials have recently garnered significant attention for their strong UV-light responsiveness, exceptional thermal stability, and theoretically predicted ultrahigh carrier mobility. In this study, we synthesized Pb and Sn-based = 1 2D RP perovskite films covering millimeter-scale areas for the first time, utilizing a one-step chemical vapor deposition (CVD) method under atmospheric conditions.

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Designing efficient and cost-effective materials is pivotal to solving the key scientific and technological challenges at the interface of energy, environment, and sustainability for achieving NetZero. Two-dimensional transition metal dichalcogenides (2D TMDs) represent a unique class of materials that have catered to a myriad of energy conversion and storage (ECS) applications. Their uniqueness arises from their ultra-thin nature, high fractions of atoms residing on surfaces, rich chemical compositions featuring diverse metals and chalcogens, and remarkable tunability across multiple length scales.

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Article Synopsis
  • The rise of Li-ion battery use has led to concerns about the supply of critical minerals like cobalt, nickel, and lithium essential for their components.
  • Recycling spent Li-ion batteries is vital for sustainability, helping to manage e-waste while ensuring a steady supply of these minerals.
  • Recent advancements in recycling methods include eco-friendly hydrometallurgy techniques and direct recycling approaches aimed at improving efficiency and reducing environmental impacts.
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Fluorite mineral holds significant importance because of its optoelectronic properties and wide range of applications. Here, we report the successful exfoliation of bulk fluorite ore (calcium fluoride, CaF) crystals into atomically thin two-dimensional fluoritene (2D CaF) using a highly scalable liquid-phase exfoliation method. The microscopic and spectroscopy characterizations show the formation of (111) plane-oriented 2D CaF sheets with exfoliation-induced material strain due to bond breaking, leading to the changes in lattice parameter.

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2D materials exhibit exceptional properties as compared to their macroscopic counterparts, with promising applications in nearly every area of science and technology. To unlock further functionality, the chemical functionalization of 2D structures is a powerful technique that enables tunability and new properties within these materials. Here, the successful effort to chemically functionalize hexagonal boron nitride (hBN), a chemically inert 2D ceramic with weak interlayer forces, using a gas-phase fluorination process is exploited.

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