▎ 摘　　要

NOVELTY - Improving calcium titanate photocatalytic activity by using utilizing pulsed laser comprises (i) placing graphene oxide and calcium titanate into container A and container B respectively by mass ratio 1:9, adding deionized water, where the volume ratio of deionized water and graphene oxide is 10:1, the volume ratio of deionized water and calcium titanate is 10:1, and ultrasonically treating for 10-30 minutes, (ii) pouring graphene oxide solution of ultrasonic dispersion in container A into container B, setting speed of magnetic stirrer to 500-1000 revolutions per minute (rpm), and stirring for 10-30 minutes to obtain precursor solution, (iii) setting laser irradiation parameters, (iv) making x = 0, (v) performing laser irradiation of precursor solution, and preparing calcium titanate and graphene oxide composite photocatalyst samples, (vi) fixing powder on sample stage, (vii) discarding the sample, (viii) applying sample to experiment of degrading methyl orange. USE - The method is useful for improving calcium titanate photocatalytic activity by using utilizing pulsed laser. ADVANTAGE - The method: improves photocatalytic activity of calcium titanate by utilizing pulsed laser light, light absorption intensity and electron transport ability, and transport speed of photogenerated electrons; inhibits recombination of electron holes; and has the advantages of simple experimental device, convenient operation and short preparation period, which is excellent for large-scale preparation and promotion. DETAILED DESCRIPTION - Improving calcium titanate photocatalytic activity by using utilizing pulsed laser comprises (i) placing graphene oxide and calcium titanate into container A and container B respectively by mass ratio 1:9, adding deionized water, where the volume ratio of deionized water and graphene oxide is 10:1, the volume ratio of deionized water and calcium titanate is 10:1, and ultrasonically treating for 10-30 minutes, (ii) pouring graphene oxide solution of ultrasonic dispersion in container A into container B, setting speed of magnetic stirrer to 500-1000 revolutions per minute (rpm), and stirring for 10-30 minutes to obtain precursor solution, (iii) setting laser irradiation parameters by fixing the laser wavelength, laser energy, spot size, spot overlap ratio, and scanning area position and size, (iv) making x = 0, setting the laser scanning speed as given in the specification, (v) performing laser irradiation of precursor solution, drying the treated precursor solution at 80-100degreesC for 10-12 hours, preparing calcium titanate and graphene oxide composite photocatalyst samples, (vi) taking 20-30 mg sample obtained in the step (v), fixing powder on sample stage for XPS characterization, observing difference delta E between binding energies of two characteristic peaks of Ti2p, obtaining relative content of titanium(III) ion by peak fitting, taking 10-20 mg sample of step (v), ultrasonically dispersing in anhydrous ethanol to form a uniform suspension, taking 2-10 ml and titrating on the copper mesh, and drying at 40-80degrees Celsius for 20-30 minutes, spraying gold on surface to prepare samples for SEM characterization to observe whether graphene oxide is recombined on the surface of calcium titanate, (vii) discarding the sample if delta E = 5.7eV is found after characterization or graphene oxide is not observed on the surface of calcium titanate in SEM characterization, or the sample remains, (viii) applying the sample retained in step (vii) to an experiment of degrading methyl orange to study its photocatalytic activity, obtaining standard curve of methyl orange concentration, preparing a methyl orange solution with a concentration of 1 g/l, and adding deionized water to obtain methyl orange solutions with concentrations of 1 mg/l, 10 mg/l, 15 mg/l, 20 mg/l, 25 mg/l and 30 mg/l, (ix) using an ultraviolet-visible spectrophotometer to measure absorbance of methyl orange solutions of different concentrations in step (viii), and selecting the test wavelength in the range of 200-720 nm, taking absorbance of methyl orange solution absorption peak at 465 nm and its corresponding concentration to draw the standard curve, taking the x-axis as the concentration, and the y-axis as the absorbance, (x) taking 80-100 mg calcium titanate and graphene oxide composite photocatalyst sample of step (vii), adding to a container with 80-100 ml methyl orange solution with a concentration of 1 mg/l, placing the container on the magnetic stirrer, then placing in the shade box, equipping the shading box with a 10-15 w ultraviolet lamp with a wavelength of 254 nm, and the distance from the liquid surface is 8-10 cm, (xi) turning on the magnetic stirrer in the case of not turning on the UV lamp, setting stirring speed to be 500-600 rpm, and reacting for 30 minutes to achieve adsorption equilibrium, (xii) completing step (xi), keeping the magnetic stirrer to continue stirring, turning on ultraviolet lamp, sampling once at each interval, sampling 3-5 ml at a time, and continuously reacting for 60-90 minutes under light conditions, (xiii) filtering sampling solution of the step (xii) using a filter membrane with a pore size of 0.22-0.30 um to remove calcium titanate and graphene oxide composite photocatalyst, (xiv) characterizing filtered sampling solution in step (xiii) using an ultraviolet-visible spectrophotometer, selecting the wavelength of the instrument in the range of 200-720 nm, and recording the absorbance of each sampling solution at 465 nm, (xv) obtaining concentration corresponding to the absorbance of each sampling solution in step (xiv) according to the standard curve obtained in step (ix), calculating kinetic constant Kx of photocatalyst according to the formula as given in the specification, (xvi) setting x = x + 1, changing the laser scanning speed as given in the specification, and repeating steps (v) to (xv) until vx reaches vmax, and (xvii) comparing different scanning speed photocatalyst by the dynamic constant Kx, when the maximum value Kx-max, namely corresponding to the highest catalytic activity, the corresponding scanning speed is titanium(III) ion self-doped calcium titanate/graphene oxide composite photocatalyst optimal preparation parameter.