Zinc　selenide　(ZnSe)　is　a　next-generation　anode　material　due　to　its　high　sodium　storage　capacity.　However,　the　poor　conductivity　and　volume　expansion　lead　to　its　capacity　attenuation　and　short　cycle　life.　Herein,　Se-vacancy　porous　ultrathin　ZnSe　nanosheet/carbon　composite　(ZnSe@NC/N-GQD)　is　reported　as　a　high-performance　anode　material　for　sodium-ion　batteries.　Organic-inorganic　hybrid　ZnSe(en)0.5　ultrathin　nanosheets　with　abundant　Se　vacancies　are　rapidly　prepared　by　electron　beam　irradiation　for　the　first　time.　Using　it　as　a　precursor,　Se-vacancy　carbon-coated　porous　ultrathin　ZnSe　nanosheets　loaded　with　nitrogen-doped　graphene　quantum　dots　(N-GQDs)　are　synthesized　via　carbonization　and　electrodeposition　process.　Through　the　design　of　ZnSe@NC/N-GQD,　the　sodium　storage　performance　can　be　effectively　improved　by　implementing　nanostructure　engineering　(porous　ultrathin　nanosheet)　via　organic–inorganic　hybrid,　defect　engineering　(Se　vacancy)　via　electron　beam　irradiation,　and　carbon　composite　(amorphous　carbon　and　N-GQD).　Consequently,　ZnSe@NC/N-GQD　delivers　a　high　capacity　of　483　mA　h　g−1　after　200　cycles　at　0.5　A　g−1,　shows　an　outstanding　rate　capability　of　381　mA　h　g−1　at　10.0　A　g−1,　and　exhibits　an　excellent　cycling　stability　of　86　%　retention　after　2800　cycles　at　5.0　A　g−1.　This　work　develops　a　new　method　to　rapidly　prepare　organic–inorganic　nanohybrids,　and　proposes　an　innovative　design　of　high-performance　ZnSe-based　anodes.　©　2024　Elsevier　B.V.