01719nas a2200181   4500008004100000022001400041245011200055210006900167260000800236300001400244490000700258520105400265100002001319700002401339700002401363700001901387856013101406       2017                        eng d  a0947-653900aElectrochemical water oxidation catalyzed by an in situ generated alpha-Co(OH)(2) film on zeolite-Y surface0 aElectrochemical water oxidation catalyzed by an in situ generate  cJUN  a8051-80570 v233 aThe design and synthesis of an efficient and robust water-oxidation catalyst with inexpensive materials remains an important challenge in the context of artificial photosynthesis. Herein, a simple but unique technique is reported to in situ generate a thin-film of alpha-Co(OH)(2) on the surface of zeolite-Y [hereafter referred to as Y-alpha-Co(OH)(2)] that acts as an efficient and stable catalyst for electrochemical water oxidation in alkaline medium. Catalyst Y-alpha-Co(OH)(2) is so stable that it retains its catalytic activity even after 2000 cyclic voltammetric cycles of water oxidation. Expectedly, the chemical composition of alpha-Co(OH)(2) on the surface of zeolite-Y remains same as that of parent Y-alpha-Co(OH)(2) after 2000 electrocatalytic cycles. A Tafel slope as low as 59 mV decade(-1) in 0.1m KOH (pH 13) suggests faster oxygen evolution kinetics (overpotential = 329 mV; turnover frequency = 0.35 mol O-2 (mol Co)(-1)s(-1) at 1 mA cm(-2)) than the existing alpha-Co(OH)(2)-based electrocatalysts operating in alkaline medium.1 aBose, Suranjana1 aDebgupta, Joyashish1 aRamsundar, Rani, M.1 aDas, Samar, K.  uhttps://library.ncl.res.in/content/electrochemical-water-oxidation-catalyzed-situ-generated-alpha-cooh2-film-zeolite-y-surface