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  ______     ___      _____    _    _    ______   
 /_____//   / _ \\   / ____|| | || | || |      \\ 
 `____ `   / //\ \\ / //---`' | || | || |  --  // 
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 /_//     `-`   `-`   `----`    `---`   `------`  
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Text this: Single metal atom decorated photocatalysts : progress and challenges