Uniform　nano-sized　calcium　hydroxide　(Ca(OH)(2))　monocrystal　powder　was　synthesized　from　calcium　oxide　in　a　surfactant　solution　via　a　digestion　method　by　decreasing　the　surface　tension　of　the　reaction　system　to　control　the　growth　of　crystalline　Ca(OH)(2).　The　Ca(OH)(2)　monocrystal　powder　samples　were　characterized　by　means　of　scanning　electron　microscopy　(SEM),　transmission　electron　microscopy　(TEM),　high　resolution　transmission　electron　microscopy　(HRTEM),　X-ray　diffraction　(XRD),　Brunauer-Emmett-Teller　(BET),　and　Fourier　transform-infrared　spectroscopy　(FT-IR).　The　NOx　adsorption　ability　of　the　samples　was　evaluated,　and　the　influence　of　various　types　and　concentrations　of　surfactants　on　powder　agglomeration　and　then　the　specific　surface　area　in　the　precipitation　process　were　studied.　The　specific　surface　area　of　the　samples　was　found　as　high　as　58　m(2)/g　and　92　m(2)/g　and　the　particle　size,　300-400　nm　and　200-300　nm　in　the　presence　of　10　wt%　PEG600　and　0.086　mL/L　SDS　at　a　reaction　time　of　5　h,　respectively.　The　product　has　an　exceptionally　strong　adsorption　ability　for　NOx,　which　makes　it　a　highly　promising　adsorbent　for　emission　control　and　air　purification.　(c)　2012　Chinese　Society　of　Particuology　and　Institute　of　Process　Engineering,　Chinese　Academy　of　Sciences.　Published　by　Elsevier　B.V.　All　rights　reserved.