Extremely low thermal conductivity in 1D soft chain structure BiSeX (X = Br, I)

June 19, 2020

The low thermal transport properties are important for applications in thermoelectrics and thermal barrier coatings. Nowadays, the strategies to acquire low thermal conductivity in bulk materials include multi-scale defect (atomic, nano- and meso-scale), heavy molecular weight, complex crystal structure, larger unit cell and strong anharmonicity.

In a recent article in Science China Materials, Prof. Li-Dong Zhao from Beihang University and co-workers proposed a new strategy to search intrinsically low thermal conductivity in one-dimensional crystal structure. By using the first-principles calculations and experimental synthesis, they found a sort of material with extremely low thermal conductivity, namely BiSeX (X= Br, I) with one-dimensional chain structure. The mechanisms behind the low thermal conductivity were revealed from the aspect of crystal structure, by neutron powder-diffraction measurements and temperature tunable aberration-corrected scanning transmission electron microscopy (STEM).

To elucidate the origins of ultralow thermal conductivity, the authors make comparisons with several analogues that exhibit cubic- (3D), layer- (2D) and chain-like (1D) crystal structures and find that the thermal conductivity shows a decreasing trend from 3D, 2D to 1D (Fig. 1), which is due to the chemical bonding strength between the low-dimensional structure becoming progressively weaker and weaker.

"Based on these guidelines, we found that the chemical bonding along the chain further weakened with added halogen atom", said Prof. Zhao. Therefore, the chemical bondings of BiSeX along all three crystallographic directions are weaker than in other compounds (Fig. 2), showing a quasi-0D crystal structure.

Different from the ultrahigh thermal conductivity diamond (> 2000 W m-1 K-1) with strong covalent bond between carbon atoms, the phonon transport in bismuth selenohalides was significantly suppressed. As a result, they exhibit extremely low thermal conductivity. "The thermal conductivity of BiSeI at 573 K reaches ~0.27 W m-1 K-1, which is close to the theoretical minimum value", emphasized by Prof. Zhao.

These findings open up a prospect of achieving low thermal conductivity materials in one-dimensional chain-containing bulk structure with potential applications in the fields of thermal barrier coatings, thermoelectric materials, etc.
This work was published online in Science China Materials and highlighted by Science (Science, 368 (2020) 1325.) (Fig. 3).

This work was supported by the National Key Research and Development Program of China (2018YFA0702100, 2018YFB0703600), the National Natural Science Foundation of China (51772012, 51632005), the National Science Foundation for Distinguished Young Scholars (51925101), Shenzhen Peacock Plan team (KQTD2016022619565991), Beijing Natural Science Foundation (JQ18004), China Postdoctoral Science Foundation Grant (2019M650429) and 111 Project (B17002).

See the article: D. Wang, et al. "Extremely low thermal conductivity from bismuth selenohalides with 1D soft crystal structure". Science China Materials (2020) (https://doi.org/10.1007/s40843-020-1407-x)

Science China Press

Related Thermal Conductivity Articles from Brightsurf:

Clemson researchers decode thermal conductivity with light
Clemson researchers examine a highly efficient thermoelectric material in a new way - by using light.

Collaboration sparks new model for ceramic conductivity
As insulators, metal oxides - also known as ceramics - may not seem like obvious candidates for electrical conductivity.

Topology-optimized thermal cloak-concentrator
Cloaking a concentrator in thermal conduction via topology optimization. A simultaneous cloaking and concentrating of heat flux is achieved through topology optimization, a computational structural design methodology.

Investigating a thermal challenge for MOFs
New research led by an interdisciplinary team across six universities examines heat transfer in MOFs and the role it plays when MOFs are used for storing fuel.

Thermal manipulation of plasmons in atomically thin films
Nanoscale photothermal effects can induce substantial changes in the optical response experienced by the probing light, thus suggesting their applications in all-optical light modulation.

Making plastic more transparent while also adding electrical conductivity
In an effort to improve large touchscreens, LED light panels and window-mounted infrared solar cells, researchers at the University of Michigan have made plastic conductive while also making it more transparent.

Extremely low thermal conductivity in 1D soft chain structure BiSeX (X = Br, I)
Researchers found a new sort of simple one-dimensional (1D) crystal structured bismuth selenohalides (BiSeX, X = Br, I) with extremely low thermal conductivity.

Minimizing thermal conductivity of crystalline material with optimal nanostructure
Japanese researchers successfully minimized thermal conductivity by designing, fabricating, and evaluating the optimal nanostructure-multilayer materials through materials informatics (MI), which combines machine learning and molecular simulation.

Scientists measured electrical conductivity of pure interfacial water
Skoltech scientists in collaboration with researchers from the University of Stuttgart, the Karlsruhe Institute of Technology and the Russian Quantum Center achieved the first systematic experimental measurements of the electrical conductivity of pure interfacial water, hence producing new results significantly extending our knowledge of interfacial water.

Atomic magnetometer points to better picture of heart conductivity
Mapping the electrical conductivity of the heart would be a valuable tool in diagnosis and disease management, but doing so would require invasive procedures, which aren't capable of directly mapping dielectric properties.

Read More: Thermal Conductivity News and Thermal Conductivity Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.