Dual-metal-driven Selective Pathway of Nitrogen Reduction in Orderly Atomic-hybridized Re2MnS6 Ultrathin Nanosheets

Nano Lett. 2020 Jul 8;20(7):4960-4967. doi: 10.1021/acs.nanolett.0c01037. Epub 2020 Jun 2.

Abstract

The future of sustainable fertilizers and carbon-free energy carrier demands innovative breakthroughs in the exploitation of efficient electrocatalysts for synthesizing ammonia (NH3) from nitrogen (N2) in mild conditions. Understanding and regulating the reaction intermediates that form on the catalyst surface through careful catalyst design could bypass certain limitations associated with ambiguous adsorbate evolution mechanism. Herein, we propose ternary intermetallic Re2MnS6 ultrathin nanosheets that include orderly hybridized Mn-Re dual-metal sites through strong Hubbard e-e interaction, demonstrating a promising selectivity toward reaction process from N2 to NH3. The ordered inclusion of Mn sites leads to a structural phase transition and appearance of nonbonding semimetal states, in which the rate-limiting activation energy barrier is significantly decreased through a conversion in reaction pathway. As a result, the performance of N2 reduction in Re2MnS6 is increased about 6.6 times compared to the single-metal ReS2.

Keywords: N2 reduction; Re2MnS6 nanosheets; atomic hybridization; dual-metal sites.