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Electronic and Hydrogen Storage Properties of Li-Terminated Linear Boron Chains Studied by TAO-DFT.

ABSTRACT: It has been extremely difficult for conventional computational approaches to reliably predict the properties of multi-reference systems (i.e., systems possessing radical character) at the nanoscale. To resolve this, we employ thermally-assisted-occupation density functional theory (TAO-DFT) to predict the electronic and hydrogen storage properties of Li-terminated linear boron chains (Li₂B_n), with n boron atoms (n?=?6, 8, …, and 16). From our TAO-DFT results, Li₂B_n, which possess radical character, can bind up to 4 H₂ molecules per Li, with the binding energies in the desirable regime (between 20 and 40?kJ/mol per H₂). The hydrogen gravimetric storage capacities of Li₂B_n range from 7.9 to 17.0?wt%, achieving the ultimate goal of the United States Department of Energy. Accordingly, Li₂B_n could be promising media for storing and releasing H₂ at temperatures much higher than the boiling point of liquid nitrogen.

SUBMITTER: Seenithurai S

PROVIDER: S-EPMC6131515 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

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Electronic and Hydrogen Storage Properties of Li-Terminated Linear Boron Chains Studied by TAO-DFT.

Seenithurai Sonai S Chai Jeng-Da JD

Scientific reports 20180910 1

It has been extremely difficult for conventional computational approaches to reliably predict the properties of multi-reference systems (i.e., systems possessing radical character) at the nanoscale. To resolve this, we employ thermally-assisted-occupation density functional theory (TAO-DFT) to predict the electronic and hydrogen storage properties of Li-terminated linear boron chains (Li2Bn), with n boron atoms (n = 6, 8, …, and 16). From our TAO-DFT results, Li2 ...[more]

PMID: 30202018

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