Two‐Dimensional Aluminum Boride AlB4 Nanosheets as a Platform to Architecture Very Rare Semiconducting Phase and Superconductor
Year: 2025
Type: article
Abstract: ABSTRACT Semiconducting phase is extremely rare and difficult to be realized in two‐dimensional (2D) aluminum borides. Here, we for the first time report the discovery of a rarely semiconducting allotrope (labeled as AlB4‐1) in 2D AlB4 nanosheets. This semiconductor is the global minimum structure in 2D space with two layers stacked together connected by strong Al‐B bonds. Systematic studies demonstrate the high thermodynamic, lattice dynamic, thermal, and mechanical stabilities of AlB4‐1. More importantly, this semiconducting AlB4‐1 shows fascinating properties and promising applications, such as, the optimal band gap (1.156 eV at HSE06 level), high carrier mobility (up to 3.14 × 103 cm2V−1s−1), substantially high solar energy conversion efficiency (21.9 %) and large optical response (106 cm−1) in the visible region. Extensive studies indiate that h‐BN can serve as an effective substrate to support and encapsulate AlB4‐1 with minimal impact on the electronic properties of AlB4‐1, laying the foundation for the real application of AlB4‐1 in electronic devices. Besides this semiconducting phase, other low‐lying allotropes (AlB4‐2 to ‐11) also display high stabilities, exotic properties and diverse applications. For example, the metallic AlB4‐4 shows Dirac cone near Fermi level and superconductivity with TC as high as 23.4K, which can be substantially enhanced to 34.1K at tensile strain of 11%. These allotropes with different shapes show diverse hypercoordinate motifs with unusual bonding patterns. Comprehensive studies demonstrate that 2D AlB4 nanosheets is a class of highly stable, multifunctional nanomaterials for diverse applications in electronics, optics, optoelectronics, nanodevices, solar energy conversion, superconductivity, nanomechanics, and so on. The present study will provide useful guidance in fabricating these interesting nanostructures and stimulate both experimental and computational efforts in this direction.
Source: SusMat
DOI: 10.1002/sus2.70019
Authors: Bingyi Song, Li‐Ming Yang
Institution: Huazhong University of Science and Technology
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,000
OpenAlex ID: W4411465746