Structural and chemical mechanisms governing stability of inorganic Janus nanotubes

Abstract

One-dimensional inorganic nanotubes hold promise for technological applications due to their distinct physical/chemical properties, but so far advancements have been hampered by difficulties in producing single-wall nanotubes with a well-defined radius. In this work we investigate, based on Density Functional Theory (DFT), the formation mechanism of 135 different inorganic nanotubes formed by the intrinsic self-rolling driving force found in asymmetric 2D Janus sheets. We show that for isovalent Janus sheets, the lattice mismatch between inner and outer atomic layers is the driving force behind the nanotube formation, while in the non-isovalent case it is governed by the difference in chemical bond strength of the inner and outer layer leading to steric effects. From our pool of candidate structures we have identified more than 100 tubes with a preferred radius below 35 Å, which we hypothesize can display distinctive properties compared to their parent 2D monolayers. Simple descriptors have been identified to accelerate the discovery of small-radius tubes and a Bayesian regression approach has been implemented to assess the uncertainty in our predictions on the radius.

First-principles insights onto structural, electronic and optical properties of Janus monolayers CrXO (X = S, Se, Te)

“…Note that the free-standing Janus structures may be more stable in the curled forms due to their asymmetry. 50 This observation is consistent with previous predictions that sheets tend to curve in response to lattice-mismatch in its structure. 51 In the present study, bending curvature is not included in our calculations.…”

Autonomous Design of Photoferroic Ruddlesden-Popper Perovskites for Water Splitting Devices

“…Thanks to methodological improvements [ 19 , 20 , 21 ] and an increase in the computational power, computational methods have been successfully used to design novel materials with desired functionalities and improved performance. Among others [ 22 ], high-throughput approaches and autonomous workflows have been used, in combination with DFT calculations, to design better catalysts [ 23 ], batteries [ 24 ], novel 2D and 1D materials [ 25 , 26 , 27 ], and solar energy conversion devices [ 4 , 28 , 29 , 30 ].…”

Workflow Engineering in Materials Design within the BATTERY 2030+ Project

“…Examples in materials science using ASE and MyQueue for fully automated and reproducible workflows include applications of solely ASE, [ 63,64 ] or the combination of ASE and MyQueue. [ 40,41,65,66 ]…”

“…Examples in materials science using ASE and MyQueue for fully automated and reproducible workflows include applications of solely ASE, [63,64] or the combination of ASE and MyQueue. [40,41,65,66] With respect to battery materials, an automated workflow for calculating crucial ion-insertion battery properties in the framework of DFT has been established using ASE and MyQueue. [65] In detail, the stability is estimated through volume changes and the convex hull energy, open-circuit voltages (OCVs) are predicted using vacancy defect calculations and finally the kinetics are estimated through calculating migration barriers employing the nudged elastic band (NEB) method (Figure 6).…”