Nanostructured　titanates　were　prepared　by　alkaline　hydrothermal　treatment　of　Ti　powder　and　NaOH　with　different　concentrations　of　NaCl　solution.　The　products　were　characterized　by　X-ray　diffraction,　scanning　electron　microscopy,　(high-resolution)　transmission　electron　microscopy,　and　ultraviolet-visible　absorbance,　Fourier-transform　infrared,　and　Raman　spectroscopies.　The　effect　on　the　titanate　morphology　of　different　concentrations　of　NaCl　in　the　hydrothermal　reaction　system　was　investigated.　In　the　presence　of　NaCl,　Ti　powder　treated　with　NaOH　initially　formed　three-dimensional　nanobelt　microspheres.　Nanobelt　growth　along　the　[1　1　0]　axis　orientation　was　inhibited,　and　the　nanobelts　were　transformed　into　wide　nanoplates　by　radial　growth.　At　high　concentrations　of　NaCl,　lamellar　nanosheets　were　exfoliated　from　the　large　particles　through　dissolution-recrystallization,　and　finally　rolled　into　nanotubes.　The　nonlinear　optical　(NLO)　properties　of　different　titanate　nanostructures　were　studied　using　the　open-aperture　Z-scan　technique,　and　a　typical　positive　NLO　effect　induced　by　incident　light　was　observed.　(C)　2013　Elsevier　B.V.　All　rights　reserved.