Activation of 2D cobalt hydroxide with 0D cobalt oxide decoration for microplastics degradation and hydrogen evolution

•Co3O4@Co(OH)2 photocatalyst was synthesized by a one-pot hydrothermal method.•Co3O4@Co(OH)2 was photocatalytic active in PS MPs degradation and H2 production.•The photocatalytic degradation was assessed by morphological changes of the MPs.•Photocatalytic H2 production was of 43 μmol g−1.•Band diagram and mechanism could be proposed for both applications.