Abstract: A method for preparing photoluminescent carbon nanodots includes preparing and drying a sample, ashing the sample, extracting the ashed sample with solvent, filtering the extracted sample, concentrating the filtered sample, dissolving the sample in water, and freeze-drying the dissolved sample. The sample is preferably a food waste residue or animal excrement.

Abstract: A method of preparing monoatomic layer black phosphorous by irradiating an ultrasound includes: putting black phosphorus into a solvent and irradiating the ultrasound; recovering a solution from a solution to which the ultrasound is irradiated; and collecting black phosphorus remaining after the solution has been recovered, putting the black phosphorus into a solvent, irradiating the ultrasound, and recovering a solution.

Abstract: A method of preparing monoatomic layer black phosphorous by irradiating an ultrasound includes: putting black phosphorus into a solvent and irradiating the ultrasound; recovering a solution from a solution to which the ultrasound is irradiated; and collecting black phosphorus remaining after the solution has been recovered, putting the black phosphorus into a solvent, irradiating the ultrasound, and recovering a solution.

Abstract: A method for preparing photoluminescent carbon nanodots includes preparing and drying a sample, ashing the sample, extracting the ashed sample with solvent, filtering the extracted sample, concentrating the filtered sample, dissolving the sample in water, and freeze-drying the dissolved sample. The sample is preferably a food waste residue or animal excrement.

Abstract: Disclosed is a method of preparing high crystalline nanoporous titanium dioxide, in which the high crystalline nanoporous titanium dioxide, which is harmless to the human body and self-purified through the decomposition of organic matters, is prepared in mass production at the room temperature through a simply synthesis method. The method includes the steps of (a) mixing a titanium precursor and a surfactant in a solvent and performing a sol-gel reaction at a room temperature; (b) maturing a reactant obtained through the sol-gel reaction at the room temperature; (c) filtering the matured reactant and washing the matured reactant; and (d) drying the washed reactant to obtain titanium dioxide having nanopores.

Abstract: Disclosed is a nanoporous photocatalyst having a high specific surface area and high crystallinity and a method for preparing the same, capable of preparing nanoporous photocatalysts, which satisfy both of the high specific surface area of 350 m2/g to 650 m2/g and high crystallinity through a simple synthetic scheme, in mass production at a low price. The nanoporous catalyst having a high specific area and high crystallinity includes a plurality of nanopores having an average diameter of about 1 nm to about 3 nm. A micro-framework of the nanoporous photocatalyst has a single crystalline phase of anatase or a bicrystalline phase of anatase and brookite, and a specific surface area of the nanoporous photocatalyst is in a range of about 350 m2/g to 650 m2/g.

Abstract: A method for preparing impurity-doped titanium dioxide photocatalysts having superior photo activity at a visible light region and an ultraviolet light region in mass production. The titanium dioxide photocatalysts are prepared in mass production using low-price reusable materials at a room temperature when titanium dioxide is doped with carbon, sulfur, nitrogen, fluorine, and phosphorous.

Abstract: Disclosed is a method of preparing high crystalline nanoporous titanium dioxide photocatalyst, capable of preparing the high crystalline nanoporous titanium dioxide photocatalyst in mass production through a simply synthesis method using an ultrasonification. The method includes the steps of (a) mixing a titanium precursor and a surfactant in a first solvent and performing a sol-gel reaction; (b) maturing a reactant obtained through the sol-gel reaction for 15 hours to 25 hours; (c) filtering the matured reactant and washing the matured reactant; (d) primarily drying the washed reactant at a temperature of 20° C. to 50° C. to obtain titanium sediments; (e) mixing the titanium sediments in a second solvent and performing an ultrasonification with respect to the mixed solution for 10 minutes to 120 minutes; and (f) secondarily drying the mixed solution, which has been subject to the ultrasonification, at a temperature of 15° C. to 45° C. to obtain titanium dioxide photocatalytic particles.

Abstract: Disclosed is a method of preparing high crystalline nanoporous titanium dioxide, in which the high crystalline nanoporous titanium dioxide, which is harmless to the human body and self-purified through the decomposition of organic matters, is prepared in mass production at the room temperature through a simply synthesis method. The method includes the steps of (a) mixing a titanium precursor and a surfactant in a solvent and performing a sol-gel reaction at a room temperature; (b) maturing a reactant obtained through the sol-gel reaction at the room temperature; (c) filtering the matured reactant and washing the matured reactant; and (d) drying the washed reactant to obtain titanium dioxide having nanopores.

Abstract: Provided is a method for analyzing the performance of an OLED through activation in-situ. The method includes placing the OLED in an in-situ chamber, driving the OLED, and analyzing a dark spot and/or thermal degradation of the OLED, such that performance of the OLED can be analyzed while driving the OLED in-situ, separated from the external environment.

Abstract: Provided is a method for analyzing the performance of an OLED through activation in-situ. The method includes placing the OLED in an in-situ chamber, driving the OLED, and analyzing a dark spot and/or thermal degradation of the OLED, such that performance of the OLED can be analyzed while driving the OLED in-situ, separated from the external environment.

Abstract: An organic electroluminescent (EL) device is provided. The organic EL device includes a cathode and an anode, a hole transporting layer (HTL) interposed between the cathode and the anode, an organic emission material layer (EML) interposed between the HTL and the anode, and an interlayer, which is formed of a halide series material including Na, interposed between the organic EML and the cathode. The organic EL device does not include a separate electron transporting layer (ETL). The interlayer works as an interface-dipole-control layer and transports electrons and blocks holes so as to provide a high light-emitting efficiency.