Two　precursors,　namely,　p-CFO-T　(tetragonal)　and　p-CFO-C　(cubic),　were　fabricated　by　a　solgel　method　via　citric　acid　and　poly(vinyl　alcohol)　complexation,　respectively.　After　H-2-reduction,　the　two　were　converted　to　Cu/Fe3O4　catalysts　of　different　complexions,　which　are　named　as　CFO-CA　and　CFO-PVA,　respectively.　The　distribution　of　Fe2+　and　Fe3+　in　the　Cu/Fe3O4　catalysts　was　studied　by　Raman　and　XPS　techniques.　It　was　disclosed　that　the　distribution　of　Fe2+　and　Fe3+　in　Fe3O4　has　an　effect　on　Cu-Fe3O4　interaction　and　catalyst　surface　basicity.　Compared　to　CFO-PVA,　CFO-CA　has　a　larger　amount　of　Fe3+,　which　mostly　sits　at　the　octahedral　sites,　leading　to　stronger　Cu-Fe3O4　interaction,　and　a　larger　amount　of　catalyst　surface　sites　that　are　of　weak　basicity.　As　a　result,　the　critical　elementary　steps　of　WGS　reaction,　viz.　water　dissociation,　-COOH　decomposition　and　CO2　desorption　are　promoted　as　reflected　in　the　lower　E-a　and　higher　catalytic　activity　of　CFO-CA.　(C)　2020　Hydrogen　Energy　Publications　LLC.　Published　by　Elsevier　Ltd.　All　rights　reserved.