MgO　nano/microparticles　with　multiple　morphologies　and　porous　structures　have　been　fabricated　via　the　surfactant　(poly(N-vinyl-2-pyrrolidone,　poly(ethylene　glycol)　(PEG),　cetyltrimethylammonium　bromide,　oleylamine　or　triblock　copolymer　P123　or　F127)　assisted　solvo-　or　hydrothermal　route　in　a　dodecylamine　or　oleic　acid　solvent.　The　as-fabricated　MgO　samples　were　characterized　by　means　of　numerous　techniques.　It　is　shown　that　the　obtained　MgO　samples　were　single-phase　and　of　cubic　in　crystal　structure;　the　particle　morphology　and　pore　architecture　mainly　depended　upon　the　surfactant,　solvent,　and　solvo-　or　hydrothermal　temperature　adopted.　The　solvothermal　process　resulted　in　polycrystalline　MgO,　whereas　the　hydrothermal　one　gave　rise　to　single-crystalline　MgO.　Surface　areas　(8-169　m(2)　g(-1))　of　the　MgO　samples　derived　solvothermally　were　lower　than　those　(181-204　m(2)　g(-1))　of　the　MgO　counterparts　derived　hydrothermally,　with　the　mesoporous　MgO　generated　after　the　PEG-assisted　hydrothermal　treatment　at　240　degrees　C　for　72　h　possessing　the　highest　surface　area.　CO2　adsorption　capacities　of　the　MgO　samples　were　in　good　agreement　with　their　surface　areas,　and　the　mesoporous　MgO　derived　hydrothermally　with　PEG　at　240　degrees　C　for　72　h　exhibited　the　largest　CO2　uptake　(368　mu　mol　g(-1))　below　350　degrees　C.　We　believe　that　such　a　high　low-temperature　adsorption　capacity　renders　the　mesoporous　magnesia　material　useful　in　the　utilization　of　acidic　gas　adsorption.　(C)　2011　Elsevier　B.V.　All　rights　reserved.