As　a　novel　medium-temperature　CO(2　)adsorbent,　K+　doped　and　graphitic　carbon　nitride　modified　layered　double　oxide　composite　(xK/CN-LDO,　x　=　15,　20,　and　25　wt%)　were　prepared　via　in-situ　synthesis　and　impregnation　methods.　Their　adsorption　performance　was　evaluated　by　thermal　gravimetric　analyzer.　g-C3N4-modified　LDO　(CN-LDO)　exhibited　a　CO2　adsorption　capacity　of　0.46　mmol/g,　1.39　times　higher　than　the　0.33　mmol/g　observed　for　LDO.　This　enhancement　was　attributed　to　the　increased　specific　surface　area　and　the　exposure　of　additional　extractable　sites.　Further　doping　with　K　significantly　enhanced　the　adsorption　uptake　of　xK/CN-LDO.　Notably,　20　K/CN-LDO　achieved　the　highest　CO2　adsorption　uptake　of　0.82　mmol/g,　representing　a　2.48-fold　increase　compared　to　LDO.　This　further　enhancement　can　be　ascribed　to　K＇s　ability　to　alter　the　distribution　of　chemical　adsorption　sites,　thereby　providing　an　optimal　number　of　basic　sites.　In-situ　DRIFTS　analysis　revealed　that　CO(2　)predominantly　existed　in　the　form　of　carbonate　species,　while　adsorption　kinetics　studies　show　that　the　dominant　mechanism　is　chemical　adsorption,　with　external　diffusion　being　the　primary　adsorption　process.　Furthermore,　20　K/CN-LDO　exhibited　significantly　higher　regeneration　efficiency　of　72.4　%　after　10　cycles,　showcasing　its　promising　practical　prospects　for　application　in　the　SEWGS　process.