Nearly　monodisperse　single-crystalline　In(OH)3　nanocubes　were　successfully　synthesized　using　In(NO3)3ṡ4.5H2O　as　indium　source　in　the　presence　of　urea　and　cetyltrimethyl　ammonium　bromide　(CTAB)　by　a　two-step　hydrothermal　process:　the　stock　solution　was　heated　at　70　°C　for　24　h　and　then　at　120　°C　for　12　h.　The　structure　and　morphology　of　the　resultant　In(OH)3　samples　were　determined　by　X-ray　powder　diffraction　(XRD),　scanning　electron　microscopy　(SEM),　and　transmission　electron　microscopy　(TEM).　The　results　revealed　that　most　of　as-synthesized　In(OH)3　nanocubes　were　uniform　in　size,　with　the　average　edge　length　of　∼700　nm.　The　influences　of　the　reaction　temperature,　the　reaction　time,　the　mineralizer,　and　the　surfactant　on　the　morphology　of　the　obtained　products　were　discussed　in　detail.　Room-temperature　photoluminescence　(PL)　spectrum　of　the　In(OH)3　nanocubes　showed　a　peculiar　strong　emission　peak　centered　at　480　nm.　Furthermore,　the　photocatalytic　properties　of　the　In(OH)3　nanocubes　were　tested.　It　was　found　that　In(OH)3　exhibited　not　only　higher　activity　for　benzene　removal,　but　also　better　H2　evolution　from　water　than　the　commercial　Degussa　P25　TiO2.　©　2008　Elsevier　Inc.　All　rights　reserved.