NOVELTY - The method comprises: (a) degreasing an aluminum substrate using an alkaline solution for 10-15 seconds; (b) activating a surface of the aluminum substrate by etching; (c) performing electrolytic oxidation on the activated aluminum substrate in the presence of phosphoric acid; (d) electrochemical dyeing the substrate with boric acid and nickel sulfide for 5-10 minutes; (e) sealing the substrate with an aqueous solution containing metal ions; and (f) applying a protective, sol-gel oxide layer having anti-reflective, anti-fogging and self-cleaning properties on the substrate.    USE - The method is useful for electrochemically producing spectrally selective absorber layers on an aluminum substrate (claimed), where the spectrally selective absorber layers are useful for solar power applications.    ADVANTAGE - The method is capable of producing the spectrally selective absorber layers with improved durability and reproducibility, constant quality and less usage of chemicals.    DETAILED DESCRIPTION - The method comprises: (a) degreasing an aluminum substrate using an alkaline solution for 10-15 seconds; (b) activating a surface of the aluminum substrate by etching; (c) performing electrolytic oxidation on the activated aluminum substrate in the presence of phosphoric acid; (d) electrochemical dyeing the substrate with boric acid and nickel sulfide for 5-10 minutes; (e) sealing the substrate with an aqueous solution containing metal ions; (f) applying a protective, sol-gel oxide layer having anti-reflective, anti-fogging and self-cleaning properties on the substrate; and (g) drying the substrate by air or hot air. A ratio of a width of a dyeing bath and a distance between a cathode and an anode in the step (c) is 3-4, preferably 3.2-3.6. A distance between a back end of the aluminum substrate and a parallel wall of the dyeing bath in the step (c) is 1/5 to 3/5, preferably 2/5 according to the width of the dyeing bath. The phosphoric acid in the step (c) has a concentration of 0.01-5%. The ratio of the width of the dyeing bath and the distance between the cathode and the anode in the step (d) is 5-7, preferably 5.8-6.6. The distance between the back end of the aluminum substrate and the parallel wall of the dyeing bath in the step (d) is 1/5 to 3/5, preferably 2/5. The distance between the back end of the aluminum substrate and the distance between the cathode to the anode is 1/2-1/3. The step (f) is carried out in the presence of nanocrystalline or nanostructured semiconductor oxides and/or dielectric oxides.