ZnO–Eu2O3　nanocomposite　was　fabricated　by　a　simple　hydrothermal　route.　This　material　forms　a　potential　class　of　photocatalysts　in　which　the　increased　absorption　behaviour　in　ZnO–Eu2O3　is　expected　to　couple　with　the　existing　characteristics　of　Eu2O3　and　ZnO　materials.　ZnO–Eu2O3　was　characterized　using　surface　analytical　(SEM,　EDS,　HR-TEM,　AFM,　XRD)　and　spectroscopic　techniques　(XPS,　DRS,PL).　From　the　XRD　patterns,　formation　of　well-crystallized　cubic　Eu2O3　and　hexagonal　wurtzite　phase　of　ZnO　were　inferred.　Presence　of　nanoflake　like　structure　with　hexagonal　ZnO　and　cubical　Eu2O3　is　shown　by　SEM　pictures.　ZnO–Eu2O3　possesses　higher　UV　and　visible　absorption　than　Eu2O3　and　ZnO.　ZnO–Eu2O3　produces　larger　methanol　oxidation　current　indicating　its　anodic　catalytic　efficiency　in　direct　methanol　fuel　cells　(DMFCs).　This　reveals　higher　electrocatalytic　activity　of　ZnO–Eu2O3　than　ZnO.　It　is　observed　that　at　−1.6　V,　cathodic　current　density　(ipc)　of　ZnO–Eu2O3　(−103.17　mA　cm−2)　for　Hydrogen　evolution　reaction　(HER)　is　more　than　five　times　of　ZnO　(−18.19　mA　cm−2)　and　the　hydrogen　evolved　with　ZnO–Eu2O3is　15.6　mL,　which　is　higher　than　that　of　ZnO　(6.8　mL).　This　indicates　the　superior　catalytic　property　of　ZnO–Eu2O3　in　water　splitting.　This　catalyst　exhibited　higher　catalytic　activity　of　99.2%　in　the　photodegradation　of　Rhodamine　B　(Rh-B)　with　natural　sunlight　in　75　min　under　neutral　pH,　whereas　Eu2O3　and　ZnO　produced　60　and　82%　degradations　in　the　same　time.　Degradation　quantum　efficiency　by　ZnO–Eu2O3　is　larger　than　ZnO　and　Eu2O3.　ZnO–Eu2O3　was　stable　and　reusable.　The　multifunctionality　of　this　catalyst　makes　it　suitable　for　energy　and　environmental　applications.　©　2020　Elsevier　B.V.