TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Components: The metal acetate is zinc acetate, cadmium acetate, platinum acetate, ferrous acetate, manganous acetate and/or cobalt acetate. The semiconductive core comprises indium arsenide, zinc selenide, cadmium sulfide, cadmium selenide, cadmium telluride, lead selenide, indium phosphide (all preferred), magnesium sulfide, magnesium selenide, magnesium telluride, calcium sulfide, calcium selenide, calcium telluride, strontium sulfide, strontium selenide, strontium telluride, barium sulfide, barium selenide, barium telluride, zinc sulfide, zinc telluride, mercury sulfide, mercury selenide, mercury telluride, aluminum sulfide, aluminum selenide, aluminum telluride, gallium sulfide, gallium selenide, gallium telluride, indium sulfide, indium selenide, indium telluride, tin sulfide, tin selenide, tin telluride, lead sulfide, lead telluride, aluminum phosphide, aluminum arsenide, aluminum antimonide, gallium nitride, gallium phosphide, gallium arsenide, gallium antimonide, indium nitride, indium antimonide, boron phosphide, silicon, germanium or its ternary and quaternary mixture, compound or solid solution.    TECHNOLOGY FOCUS - ORGANIC CHEMISTRY - Preferred Method: The method further comprises: heating the reaction dispersion to 65-250 degrees C; and redispersing a semiconductor nanocrystal in hexane, chloroform and/or toluene. The step of mixing the semiconductive core, metal precursor solution and sulfur precursor solution comprises first adding the metal precursor solution to the semiconductive core and second adding the sulfur precursor solution. Preferred Components: The non-polar solvent is octadecene. The sulfur precursor comprises thiourea or an alcohol. EXAMPLE - Cadmium oxide (0.096 g) and stearic acid (0.854 g) were added into a 25 ml three-neck flask and heated to 200 degrees C with stirring until the solid became a transparent liquid. The flask was cooled to room temperature. Trioctylphosphine oxide (1.875 g), hexadecylamine (1.875 g) and 1-octadecene (10 g) were transferred into the flask and then heated to 280 degrees C. An injection solution was prepared by mixing selenium (0.356 g), trioctylphosphine (3.204 g) and 1-octadecene (1.375 g). The solution was swiftly injected into the flask by using a 10 ml syringe with a large bore needle. Different sizes of cadmium selenide quantum dots can be obtained by varying the reaction times (from a few seconds to a few minutes) at high temperature then quenched in cold chloroform. The reaction was run under ultra-pure nitrogen flow. The crude quantum dots were precipitated by acetone and methanol, and then centrifuged at 4500 rpm for 10 minutes. The nanocrystal pellet was re-dissolved in chloroform, filtered and store under dark.