The　protonic　material　La2Ce2O7　exhibits　good　tolerance　to　H2O　and　CO2　compared　to　BaCeO3-based　materials　and　has　become　increasingly　popular　for　operation　at　low-to-intermediate　temperatures　in　protonic　ceramic　fuel　cells.　In　this　work,　doping　La2Ce2O7　with　Na　in　a　series　with　varying　compositions　is　studied.　All　of　the　precursors　are　prepared　by　a　common　citrate-nitrate　combustion　method.　X-ray　diffraction　images　reveal　that　all　of　the　La2-xNaxCe2O7-δ　samples　have　a　cubic　structure.　The　La2-xNaxCe2O7-δ　pellets　are　characterized　by　scanning　electron　microscopy　and　are　observed　to　be　dense　without　holes.　The　effects　of　Na-doping　on　the　La2Ce2O7　electrical　conductivity　are　carefully　investigated　in　air　at　350–800　°C　and　5%H2-95%　Ar　environments　at　350–700　°C.　It　is　found　that　different　levels　of　Na　doping　in　La2Ce2O7　are　conducive　to　improving　the　electrical　conductivity　and　sinterability.　Among　the　pellets,　La1.85Na0.15Ce2O7-δ　exhibited　the　highest　electrical　conductivity　in　air　and　5%　H2-95%　Ar　atmospheres.　Anode-supported　half　cells　with　La1.85Na0.15Ce2O7-δ　electrolyte　are　also　fabricated　via　a　dry-pressing　process,　and　the　corresponding　single　cell　exhibited　a　desirable　power　performance　of　501　mW　cm−2　at　700　°C.　The　results　demonstrate　that　La1.85Na0.15Ce2O7-δ　is　a　promising　proton　electrolyte　with　high　conductivity　and　sufficient　sinterability　for　use　in　protonic　ceramic　fuel　cells　operating　at　reduced　temperatures.　©　2017