Ni/Si-Codoped TiO2 Nanostructure Photoanode for Enhanced Photoelectrochemical Water Splitting

Abstract

We synthesized Ni/Si-codoped TiO2 nanostructures for photoelectrochemical (PEC) water splitting, by electrochemical anodization of Ti-1Ni-5Si alloy foils in ethylene glycol/glycerol solutions containing a small amount of water. The effects of annealing temperature on PEC properties of Ni/Si-codoped TiO2 photoanode were investigated. We found that the Ni/Si-codoped TiO2 photoanode annealed at 700 °C had an anatase-rutile mixed phase and exhibited the highest photocurrent density of 1.15 mA/cm2 at 0 V (vs. Ag/AgCl), corresponding to a photoconversion efficiency of 0.70%, which was superior to Ni-doped and Si-doped TiO2. This improvement in PEC water splitting could be attributed to the extended light absorption, faster charge transfer, possibly lower charge recombination, and longer lifetime.

Electrochemical Fabrication of Ternary Black Ti‐Mo‐Ni Oxide Nanotube Arrays for Enhanced Photoelectrochemical Water Oxidation

“…Furthermore, as concluded from XRD patterns shown in Figure , the rutile /anatase ratio of the hydrogenated TiO 2 crystal structure was slightly higher than that of the air‐treated counterpart. Consequently, an enhanced photoactivity of the reduced black sample could be assigned to the creation of more interface defect states, which could act as trapping sites for charge carriers, resulting in less charge carriers recombination . By analyzing these findings and compare them with the air‐annealed samples, which were previously discussed in our previous work, it is obvious that the photocurrent of the H 2 ‐ treated photoanode at 10 h is almost five times greater than that of the air‐annealed counterpart.…”

Effect of SiO2/Al2O3 ratio on the electrochemical performance of amorphous zeolite loaded with cobalt oxide grown via steam-assisted crystallization method

“…So we can conclude that among these results, the best result is obtained for Co/H-AZ 2 (mass ratio 2: 8.3) compared to Co/H-AZ 1 (mass ratio 1: 6.3). 56,57 It can be seen that the proton H + and the SiO 2 /Al 2 O 3 mass ratio have played a significant role.…”

Enhanced Photoelectrochemical Water Splitting Performance of Ni/Si-doped TiO2 Photoanode Fabricated through Electrochemical Reduction in Aqueous Solutions

“…Ni/Si-doped TiO 2 samples were fabricated by anodizing these homogenized alloy plates with Pt foil as the anode. 31 The anodization experiments were performed at 40 V for 90 min in a solution containing 10 vol% ethylene glycol/glycerol + 0.4 M NH 4 F + 0.3 M (NH 4 ) 2 SO 4 + 2 vol% H 2 O at 25 °C controlled by a water bath. Finally, the amorphous anodized samples were converted to crystalline structures through heat treating at 700 °C in air for 2 h. For reference, undoped TiO 2 samples were fabricated on pure Ti alloy (99.99 wt% purity) plates under the same electrochemical anodization condition.…”