Method for electrochemical water splitting

Abstract

An electrode including a transparent substrate and a layer of a perovskite-based nanocomposite (PTNC) material at least partially covering a surface of the transparent substrate. The PTNC material includes gold (Au) nanoparticles, graphitic carbon nitride (g-C3N4) nanoparticles, and perovskite-based nanoparticles through synergistic interaction. A method of making the electrode is described.

1 . (canceled) 
     
     
         2 . The method of claim  19 , wherein the transparent substrate is a glass substrate, and wherein the glass substrate is at least one selected from the group consisting of a fluorine doped tin oxide (FTO) glass substrate, a tin doped indium oxide (ITO) glass substrate, an aluminum doped zinc oxide (AZO) glass substrate, a niobium doped titanium dioxide (NTO) glass substrate, an indium doped cadmium oxide (ICO) glass substrate, an indium doped zinc oxide (IZO) glass substrate, a fluorine doped zinc oxide (FZO) glass substrate, a gallium doped zinc oxide (GZO) glass substrate, an antimony doped tin oxide (ATO) glass substrate, a phosphorus doped tin oxide (PTO) glass substrate, a zinc antimonate glass substrate, a zinc oxide glass substrate, a ruthenium oxide glass substrate, a rhenium oxide glass substrate, a silver oxide glass substrate, and a nickel oxide glass substrate. 
     
     
         3 . The method of claim  19 , wherein the transparent substrate is a FTO glass substrate. 
     
     
         4 . The method of claim  19 , wherein the Au nanoparticles present in the PTNC material are spherical nanoparticles having an average diameter of 5 to 50 nanometers (nm), and an interplanar spacing d (111) of the (111) plane in a range of 0.15 to 0.3 nm as determined by X-ray diffraction. 
     
     
         5 . The method of claim  19 , wherein the g-C 3 N 4  nanoparticles present in the PTNC material are nanosheets having an average thickness of 1 to 20 nm, and an interplanar spacing d(002) of the (002) plane in a range of 0.25 to 0.35 nm as determined by X-ray diffraction. 
     
     
         6 . The method of claim  19 , wherein the perovskite-based nanoparticles present in the PTNC material are spherical nanoparticles having an average diameter of 50 to 200 nm, and an interplanar spacing d(100) of the (100) plane in a range of 0.35 to 0.45 nm as determined by X-ray diffraction. 
     
     
         7 . The method of claim  19 , wherein the PTNC material comprises 20 to 40 wt. % carbon, 10 to 30 wt. % strontium, 10 to 30 wt. % titanium, 10 to 30 wt. % zirconium, 10 to 30 wt. % barium, 10 to 30 wt. % niobium, 10 to 30 wt. % lanthanum, 10 to 30 wt. % manganese, 10 to 30 wt. % aluminum, 10 to 20 wt. % oxygen, 10 to 20 wt. % gold, and 5 to 15 wt. % nitrogen, each wt. % based on a total weight of the PTNC material by energy dispersive X-ray (EDX). 
     
     
         8 . The method of claim  19 , wherein the electrode has a current density of 150 to 250 milliamperes per square centimeter (mA/cm 2 ) in an acidic medium at a scan rate of 5 to 20 millivolts per second (mV/s). 
     
     
         9 . The method of claim  19 , wherein the electrode has an overpotential of 0.1 to 0.3 volts (V) in an acidic medium at a scan rate of 5 to 20 mV/s. 
     
     
         10 . The method of claim  19 , wherein the electrode has a Tafel slope of 40 to 80 millivolts per decade (mV/decade) in an acidic medium at a scan rate of 5 to 20 mV/s. 
     
     
         11 - 18 . (canceled) 
     
     
         19 . A method for electrochemical water splitting, comprising:
 applying a potential between an anode and a cathode in an electrochemical cell containing an electrolyte to form hydrogen and oxygen;   wherein the cathode comprises an electrode having a transparent substrate, and a layer of a perovskite-based nanocomposite (PTNC) material at least partially covering a surface of the transparent substrate; and   wherein the electrolyte comprising an aqueous solution of an acid at a concentration of 0.001 to 3 molars (M), and wherein the PTNC material comprises gold (Au) nanoparticles, graphitic carbon nitride (g-C 3 N 4 ) nanoparticles, and perovskite-based nanoparticles.   
     
     
         20 . The method for  claim 19 , wherein the acid comprises at least one of sulfuric acid, nitric acid, phosphoric acid, boric acid, and citric acid.