--- res: bibo_abstract: - Redox mediators could catalyse otherwise slow and energy-inefficient cycling of Li–S and Li–O2 batteries by shuttling electrons or holes between the electrode and the solid insulating storage materials. For mediators to work efficiently they need to oxidize the solid with fast kinetics but with the lowest possible overpotential. However, the dependence of kinetics and overpotential is unclear, which hinders informed improvement. Here, we find that when the redox potentials of mediators are tuned via, for example, Li+ concentration in the electrolyte, they exhibit distinct threshold potentials, where the kinetics accelerate several-fold within a range as small as 10 mV. This phenomenon is independent of types of mediator and electrolyte. The acceleration originates from the overpotentials required to activate fast Li+/e− extraction and the following chemical step at specific abundant surface facets. Efficient redox catalysis at insulating solids therefore requires careful consideration of the surface conditions of the storage materials and electrolyte-dependent redox potentials, which may be tuned by salt concentrations or solvents.@eng bibo_authorlist: - foaf_Person: foaf_givenName: Deqing foaf_name: Cao, Deqing foaf_surname: Cao - foaf_Person: foaf_givenName: Xiaoxiao foaf_name: Shen, Xiaoxiao foaf_surname: Shen - foaf_Person: foaf_givenName: Aiping foaf_name: Wang, Aiping foaf_surname: Wang - foaf_Person: foaf_givenName: Fengjiao foaf_name: Yu, Fengjiao foaf_surname: Yu - foaf_Person: foaf_givenName: Yuping foaf_name: Wu, Yuping foaf_surname: Wu - foaf_Person: foaf_givenName: Siqi foaf_name: Shi, Siqi foaf_surname: Shi - foaf_Person: foaf_givenName: Stefan Alexander foaf_name: Freunberger, Stefan Alexander foaf_surname: Freunberger foaf_workInfoHomepage: http://www.librecat.org/personId=A8CA28E6-CE23-11E9-AD2D-EC27E6697425 orcid: 0000-0003-2902-5319 - foaf_Person: foaf_givenName: Yuhui foaf_name: Chen, Yuhui foaf_surname: Chen bibo_doi: 10.1038/s41929-022-00752-z bibo_volume: 5 dct_date: 2022^xs_gYear dct_identifier: - UT:000763879400001 dct_isPartOf: - http://id.crossref.org/issn/2520-1158 dct_language: eng dct_publisher: Springer Nature@ dct_subject: - Process Chemistry and Technology - Biochemistry - Bioengineering - Catalysis dct_title: Threshold potentials for fast kinetics during mediated redox catalysis of insulators in Li–O2 and Li–S batteries@ ...