01783nas a2200229   4500008004100000245010400041210006900145260000800214300001500222490000600237520097200243653001901215653001601234653003501250653002601285653003001311100002201341700002401363700002401387700001801411856012401429       2022                        eng d00aTuning of oxygen reduction pathways through structural variation in transition metal-doped Ba2In2O50 aTuning of oxygen reduction pathways through structural variation  cJAN  ae2021011630 v93 aAbstract Oxygen reduction reaction (ORR) can take place either through a two-electron pathway to form H2O2 or through a four-electron pathway to form H2O. Both the reactions are important in the respective fields, viz., H2O2 production as well as fuel cell technology, and rational design of catalysts is mandatory to acquire high energy efficiency in both cases. Here, we report the structure-electrochemical property correlation of a series of perovskite related brownmillerite compounds, Ba2In0.75M0.25O5 (M=Mn/Fe/Co/Ni/Cu), synthesized by solid-state method. On transition metal doping, octahedral distortions were observed, and the highly disordered material tends to follow the 4e transfer mechanism. More symmetrical structures followed the 2e pathway to form H2O2 as the product with high peroxide selectivity. The distortion in the octahedral arrangement can be a descriptor to finetune the selectivity of the catalysts towards the 2e and 4e pathways of ORR.10abrownmillerite10aDescriptors10aElectrochemical H2O2 synthesis10aOctahedral distortion10aoxygen reduction reaction1 aThundiyil, Shibin1 aPandikassala, Ajmal1 aKurungot, Sreekumar1 aDevi, Nandini  uhttps://library.ncl.res.in/content/tuning-oxygen-reduction-pathways-through-structural-variation-transition-metal-doped