Transition metal tungstates AWO4 (A2+  = Fe, Co, Ni, and Cu) thin films and their photoelectrochemical behavior as photoanode for photocatalytic applications

The Role of Lattice Defects on the Optical Properties of TiO2 Nanotube Arrays for Synergistic Water Splitting

“…An alternative method of determining the V FB is based on the measurement of the photocurrent as a function of applied potential, following the Gartner–Butler (G–B) model (Figure S10). The V FB was estimated by the intersection of the photocurrent squared and the potential axis. The G–B equation relates the net measured photocurrent ( I photo ) to the extent of band bending in the semiconductor: I photo ≈ I 0 , λ α λ true( 2 eε 0 ε r n 0 true) 1 / 2 true( V − V FB true) 1 / 2 where I 0,λ is the incident photon flux, α λ (wavelength-dependent) is the material absorption coefficient, and n o is the donor concentration ( n o ≈ N D ).…”

“…NaBH 4 treatment increases the N D of TiO 2 NTAs, by creating surface OVs that serve as electron donors . The increase in N D often enhances the electrical conductivity as well as charge transport in TiO 2 . Using the V FB and the optical band gap values it was calculated the VB and CB energy positions.…”

“…An alternative method of determining the V FB is based on the measurement of the photocurrent as a function of applied potential, following the Gartner–Butler (G–B) model (Figure S10). The V FB was estimated by the intersection of the photocurrent squared and the potential axis. The G–B equation relates the net measured photocurrent ( I photo ) to the extent of band bending in the semiconductor: where I 0,λ is the incident photon flux, α λ (wavelength-dependent) is the material absorption coefficient, and n o is the donor concentration ( n o ≈ N D ).…”

“…84 The increase in N D often enhances the electrical conductivity as well as charge transport in TiO 2 . 85 Using the V FB and the optical band gap values it was calculated the VB and CB energy positions. It has been reported that the CB potential (E CB ) of n-type semiconductors is 0.1 to 0.2 V more negative than their V FB values.…”

Investigation of supercapacitor properties using iron tungsten porous electrode in neutral aqueous electrolyte

“…The preparation of iron tungstate resin follows the steps as shown in Fig. 1 as previous study [24]. (1) A tungsten metal citrate (Cit-W, pH = 7) was initially prepared using deionized water (DI-H 2 O) as a solvent, 0.135 mol citric acid (C 6 H 8 O 7 ) as a complexing agent and 0.045 mol tungstic acid (H 2 WO 4 ) as a network modi er forming a transparent solution with concentration of 0.4256 µmol L -1 .…”