[Paper Review] High-throughput computational discovery of 40 ultralow thermal conductivity and 20 highly anisotropic crystalline materials

Ankit Jain, Harish P Veeravenkata+2 more|arXiv (Cornell University)|Apr 7, 2022

Thermal properties of materials5 citations

TL;DR

This study presents a high-throughput density functional theory (DFT)-based computational screening of 225 stable ternary semiconductors to identify materials with ultralow thermal conductivity and high thermal transport anisotropy. Using efficient anharmonic force constant extraction, it identifies 40 materials with thermal conductivity below 1 W/m-K, including SbRbK₂ with 0.16 W/m-K, and 20 materials with anisotropy exceeding the highest previously reported value, with the maximum reaching 12.6.

ABSTRACT

We performed ab-initio driven density functional theory-based high throughput computations to search for materials with low thermal conductivity and high thermal transport anisotropy. We shortlisted a pool of 429 stable ternary semiconductors from the Materials Project and obtained phonon thermal conductivity by solving the Boltzmann transport equation on 225 materials. We found the lowest thermal conductivity of 0.16 W/m-K in SbRbK 2 and 40 materials with a thermal conductivity lower than 1 W/m-K at 300 K. For anisotropic thermal transport, we have identified six materials with anisotropy larger than 5 and 20 with thermal transport anisotropy higher than the largest reported literature value.

Motivation & Objective

• To accelerate the discovery of novel materials with ultralow thermal conductivity for thermoelectric and thermal insulation applications.
• To overcome the computational bottleneck of traditional ab-initio thermal conductivity calculations by leveraging efficient anharmonic force constant extraction methods.
• To systematically identify materials with high thermal transport anisotropy, a property critical for directional heat management.
• To expand the search beyond known material classes by performing full DFT calculations on a broad set of 225 stable ternary semiconductors.
• To provide a computationally efficient, high-throughput framework for predicting phonon thermal transport properties with high accuracy.

Proposed method

• Performed ab-initio DFT calculations on 429 stable ternary semiconductors from the Materials Project, filtering for thermodynamic and structural stability.
• Applied the Boltzmann transport equation (BTE) to compute phonon thermal conductivity at 300 K using temperature-dependent anharmonic force constants extracted via the stochastic thermal snapshot method.
• Used a consistent set of well-converged simulation parameters to ensure reliability and comparability across all 225 materials.
• Screened materials based on electronic bandgap (>0.2 eV), absence of lanthanides, actinides, noble metals, and highly ionic compounds.
• Calculated thermal conductivity anisotropy as the ratio of maximum to minimum thermal conductivity across crystallographic directions.
• Validated results against known benchmarks, such as boron arsenide, to ensure accuracy of the computational pipeline.

Experimental results

Research questions

• RQ1 What is the lowest achievable phonon thermal conductivity among stable ternary semiconductors using ab-initio DFT-based high-throughput screening?
• RQ2 Which materials exhibit the highest thermal transport anisotropy, and how do they compare to previously reported values?
• RQ3 Can efficient anharmonic force constant extraction methods enable large-scale, accurate thermal conductivity predictions at reduced computational cost?
• RQ4 How does the distribution of thermal conductivity and anisotropy vary across different crystal systems and chemical compositions?
• RQ5 Which material compositions or structural motifs consistently lead to ultralow thermal conductivity or high anisotropy?

Key findings

• The lowest phonon thermal conductivity identified is 0.16 W/m-K in SbRbK₂ at 300 K, the lowest reported to date.
• A total of 40 materials exhibit thermal conductivity below 1 W/m-K, indicating a rich pool of candidates for thermoelectric and thermal barrier applications.
• The highest thermal transport anisotropy observed is 12.6 in a covalently bonded compound, significantly exceeding previously reported values.
• Six materials exhibit anisotropy greater than 5, and 20 materials exceed the highest anisotropy value reported in the literature prior to this study.
• The computational framework enabled accurate thermal conductivity predictions at 1–3 orders of magnitude lower cost than traditional methods, facilitating large-scale screening.
• The study demonstrates that complex ternary compounds with specific atomic arrangements and low symmetry can achieve both ultralow thermal conductivity and high anisotropy, expanding the design space for functional materials.