Intrinsic Descriptor Guided Noble Metal Cathode Design for Li-CO₂ Battery.

Abstract

To date, the effect of noble metal (NM) electronic structures on CO₂ reaction activity remains unknown, and explicit screening criteria are still lacking for designing highly efficient catalysts in CO₂ -breathing batteries. Herein, by preferentially considering the decomposition of key intermediate Li₂ CO₃ , an intrinsic descriptor constituted of the <math xmlns="http://www.w3.org/1998/Math/MathML"> <semantics><msub><mi>d</mi> <mrow><msup><mi>x</mi> <mn>2</mn></msup> <mo>-</mo> <msup><mi>y</mi> <mn>2</mn></msup> </mrow> </msub> <annotation>${{\rm{d}}}_{{x}^2 - {y}^2}$</annotation></semantics> </math> orbital states and the electronegativity for predicting high-performance cathode material are discovered. As a demonstration, a series of graphene-supported noble metals (NM@G) as cathodes are fabricated via a fast laser scribing technique. Consistent with the preliminary prediction, Pd@G exhibits an ultralow overpotential (0.41 V), along with superior cycling performance up to 1400 h. Moreover, the overall thermodynamic reaction pathways on NM@G confirm the reliability of the established intrinsic descriptor. This basic finding of the relationship between the electronic properties of noble metal cathodes and the performance of Li-CO₂ batteries provides a novel avenue for designing remarkably efficient cathode materials for metal-CO₂ batteries.