Sodium　metal　as　the　anodes　for　sodium　metal　batteries　(SMBs)　possess　several　advantages,　including　high　theoretical　capacity,　high　abundance　and　low-cost,　which　make　SMBs　formidable　contenders　for　constructing　alternative　batteries　to　lithium-based　ones.　However,　the　presence　of　an　undesirable　solid　electrolyte　interface　(SEI)　between　Na　metal　and　liquid　electrolyte　can　result　in　sluggish　Na　ion　transfer　kinetics,　substantial　consumption　of　electrolyte,　and　dendrite　growth　issues,　particularly　at　ultra-low　temperatures.　To　address　these　challenges,　a　three-dimensional　(3D)　artificial　protection　layer　composed　of　Na3Bi　and　NaF　(NBF)　on　the　Na　anode　surface　is　successfully　fabricated　through　a　simple　in-situ　reaction.　Both　theoretical　and　experimental　findings　demonstrate　that　this　artificial　protection　layer　exhibits　strong　sodiophilicity,　enhanced　ionic　conductivity,　excellent　and　electronic　insulation　property,　which　can　effectively　suppress　the　continuous　electrolyte　decomposition.　As　a　result,　at　low　operating　temperatures　(−30　°C),　such　an　NBF　symmetric　cell　achieves　a　long　cycle　life　of　over　1400　h　(0.1　mA　cm−2@　0.1　mAh　cm−2).　And　the　electrochemical　performance　of　NBF　is　exceptional　when　it　is　utilized　as　the　anodes　in　symmetric　cells,　demonstrating　a　cycle-life　exceeding　2390　h　at　0.5　mA　cm−2@0.5　mAh　cm−2,　and　also　in　sodium　metal　full　cells　at　5C,　exhibiting　over　2000　cycles.　Therefore,　the　results　provide　support　for　the　possibility　of　utilizing　the　artificial　protection　layer　in　developing　a　safeguarding　coating　for　sodium　metal　anodes.　©　2025　Elsevier　B.V.