Reliable Prediction of New Quantum Materials for Topological and Renewable-Energy Applications: A High-Throughput Screening

Mixed Stochastic-Deterministic Approach for Many-Body Perturbation Theory Calculations

We present an approach for GW calculations of quasiparticle energies with quasiquadratic scaling by approximating high-energy contributions to the Green's function in its Lehmann representation with effective stochastic vectors. The method is easy to implement without altering the GW code, converges rapidly with stochastic parameters, and treats systems of various dimensionality and screening response. Our calculations on a 5.75° twisted MoS_{2} bilayer show how large-scale GW methods include geometry relaxations and electronic correlations on an equal basis in structurally nontrivial materials.

Unveiling the Catalytic Potential of Topological Nodal-Line Semimetal AuSn4 for Hydrogen Evolution and CO2 Reduction

In recent years, the correlation between the existence of topological electronic states in materials and their catalytic activity has gained increasing attention, due to the exceptional electron conductivity and charge carrier mobility exhibited by quantum materials. However, the physicochemical mechanisms ruling catalysis with quantum materials are not fully understood. Here, we investigate the chemical reactivity, ambient stability, and catalytic activity of the topological nodal-line semimetal AuSn₄. Our findings reveal that the surface of AuSn₄ is prone to oxidation, resulting in the formation of a nanometric SnO₂ skin. This surface oxidation significantly enhances the material's performance as a catalyst for the hydrogen evolution reaction in acidic environments. We demonstrate that the peculiar atomic structure of oxidized AuSn₄ enables the migration of hydrogen atoms through the Sn-O layer with a minimal energy barrier of only 0.19 eV. Furthermore, the Volmer step becomes exothermic in the presence of Sn vacancies or tin-oxide skin, as opposed to being hindered in the pristine sample, with energy values of -0.62 and -1.66 eV, respectively, compared to the +0.46 eV energy barrier in the pristine sample. Our model also suggests that oxidized AuSn₄ can serve as a catalyst for the hydrogen evolution reaction in alkali media. Additionally, we evaluate the material's suitability for the carbon dioxide reduction reaction, finding that the presence of topologically protected electronic states enhances the migration of hydrogen atoms adsorbed on the catalyst to carbon dioxide.