{"status":"public","date_created":"2020-04-01T10:10:21Z","author":[{"full_name":"Prehal, Christian","last_name":"Prehal","first_name":"Christian"},{"first_name":"Aleksej","last_name":"Samojlov","full_name":"Samojlov, Aleksej"},{"first_name":"Manfred","last_name":"Nachtnebel","full_name":"Nachtnebel, Manfred"},{"full_name":"Kriechbaum, Manfred","first_name":"Manfred","last_name":"Kriechbaum"},{"first_name":"Heinz","last_name":"Amenitsch","full_name":"Amenitsch, Heinz"},{"id":"A8CA28E6-CE23-11E9-AD2D-EC27E6697425","full_name":"Freunberger, Stefan Alexander","last_name":"Freunberger","orcid":"0000-0003-2902-5319","first_name":"Stefan Alexander"}],"oa_version":"Preprint","abstract":[{"lang":"eng","text":"Electrodepositing  insulating  and  insoluble  Li2O2  is  the  key  process  during  discharge  of  aprotic  Li-O2 batteries  and  determines  rate,  capacity,  and  reversibility.  Current  understanding  states  that  the partition  between  surface  adsorbed  and  solvated  LiO2  governs  whether  Li2O2  grows  as  surface  film, leading to low capacity even at low rates, or in solution, leading to particles and high capacities. Here we show that Li2O2 forms to the widest extent as particles via solution mediated LiO2 disproportionation. We  describe  a  unified  Li2O2  growth  model  that  conclusively  explains  capacity  limitations  across  the whole range of electrolytes. Deciding for particle morphology, achievable rate and capacities are species mobilities,   electrode   specific   surface   area   (determining  true   areal   rate)   and   the  concentration distribution of associated LiO2 in solution. Provided that species mobilities and surface are high, high, capacities are possible even with low-donor-number electrolytes, previously considered prototypical for low   capacity   via   surface   growth.   The   tools   for   these   insights   are   microscopy,   hydrodynamic voltammetry, a numerical reaction model, and in situ small/wide angle X-ray scattering (SAXS/WAXS). Combined with sophisticated data analysis, SAXS allows retrieving rich quantitative information from complex multi-phase systems. On a wider perspective, this SAXS method is a powerful in situ metrology with  atomic  to  sub-micron  resolution  to  study  mechanisms  in  complex  electrochemical  systems  and beyond. "}],"date_updated":"2020-04-06T10:36:21Z","_id":"7627","oa":1,"page":"50","type":"preprint","publication_status":"submitted","language":[{"iso":"eng"}],"title":"A revised O2 reduction model in Li-O2 batteries as revealed by in situ small angle X-ray scattering","main_file_link":[{"open_access":"1","url":"https://doi.org/10.26434/chemrxiv.11447775.v1"}],"date_published":"2019-12-26T00:00:00Z","extern":"1","citation":{"ama":"Prehal C, Samojlov A, Nachtnebel M, Kriechbaum M, Amenitsch H, Freunberger SA. A revised O2 reduction model in Li-O2 batteries as revealed by in situ small angle X-ray scattering.","ieee":"C. Prehal, A. Samojlov, M. Nachtnebel, M. Kriechbaum, H. Amenitsch, and S. A. Freunberger, “A revised O2 reduction model in Li-O2 batteries as revealed by in situ small angle X-ray scattering.” ChemRxiv.","mla":"Prehal, Christian, et al. <i>A Revised O2 Reduction Model in Li-O2 Batteries as Revealed by in Situ Small Angle X-Ray Scattering</i>. ChemRxiv.","short":"C. Prehal, A. Samojlov, M. Nachtnebel, M. Kriechbaum, H. Amenitsch, S.A. Freunberger, (n.d.).","ista":"Prehal C, Samojlov A, Nachtnebel M, Kriechbaum M, Amenitsch H, Freunberger SA. A revised O2 reduction model in Li-O2 batteries as revealed by in situ small angle X-ray scattering.","apa":"Prehal, C., Samojlov, A., Nachtnebel, M., Kriechbaum, M., Amenitsch, H., &#38; Freunberger, S. A. (n.d.). A revised O2 reduction model in Li-O2 batteries as revealed by in situ small angle X-ray scattering. ChemRxiv.","chicago":"Prehal, Christian, Aleksej Samojlov, Manfred Nachtnebel, Manfred Kriechbaum, Heinz Amenitsch, and Stefan Alexander Freunberger. “A Revised O2 Reduction Model in Li-O2 Batteries as Revealed by in Situ Small Angle X-Ray Scattering.” ChemRxiv, n.d."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","month":"12","article_processing_charge":"No","year":"2019","publisher":"ChemRxiv","day":"26"}