Effect of B-Doping and Manifestation on TiO₂-Supported IrO₂ for Oxygen Evolution Reaction in Water Electrolysis

Abstract

To commercialize hydrogen production by proton exchange membrane (PEM) electrolysis, the amount of rare and precious metal (iridium) required for anodic oxygen evolution reaction (OER) must be greatly reduced. In order to solve the problem, carrier loading is used to reduce the amount of iridium. Unlike the carrier modified by conventional metal element doping, this work doped the carrier with the nonmetallic element and then prepared IrO 2 /TiB x O 2 composite catalyst using the Adams melting method. B-doped TiO 2 supports with different doping amounts show the main phase rutile structure. Among them, the conductivity of B-doped carrier shows an increasing trend with the increase of doping amount, because boron can form holes and negative centers after doping, and more carriers improve the conductivity of the support. In addition, since element B is manifested from inside to outside on the support, B can affect the catalytic process. After the manifestation of element B, the carrier loaded with IrO 2 exhibited superior electrocatalytic properties. The voltammetric charge per unit mass of 40IrO 2 /TiB 0.3 O 2 #2 (where #2 represents B after manifestation) reaches 1970 mC (cm 2 mg) −1 , the corresponding overpotential is 273 mV at a current density of 10 mA/cm −2 , and the Tafel slope is 61.9 mV/dec Also, the charge transfer resistance is only 15 Ω. Finally, in the stability test, the composite catalyst is also better than pure IrO 2 in the 20 000 s operation. Therefore, element B has an unexpectedly positive effect on the catalytic progress on the surface of the support after its manifestation.

Strong Metal‐Support Interactions in ZrO2‐Supported IrOx Catalyst for Efficient Oxygen Evolution Reaction

“…The authors have cited additional references within the Supporting Information. [14,31,[33][34][35][36][37][38][39][40][41][42][43][44][45][46][47][48][49][50]52,53,56,57,60,69,[92][93][94][95][96][97][98][99][131][132][133][134][135][136][137][138][139][140][141][142][143]…”

“…The authors have cited additional references within the Supporting Information [14,31,33–50,52,53,56,57,60,69,92–99,131–143] …”

“…[6,[24][25][26] Tin based oxide supports (SnO 2 , doped-SnO 2 : antimony doped tin oxide, indium doped tin oxide, fluorine doped tin oxide etc. ), [27][28][29][30][31][32][33][34][35][36][37][38][39][40][41][42] titanium-based oxide supports (TiO x , Ti n O (2-n) , doped titanium oxide), [37,[43][44][45][46][47][48][49][50] Ta 2 O 5 , [51] Nbbased oxides, [52][53][54][55] are by far the most popular metal oxide supports due to their stability under oxidative conditions, and the tunable electrical conductivity for some, and possible metal-support interactions. [6] For instance, Oh et al reported a reduced effective oxide thickness in IrO 2 /ATO as compared to IrO x /C, with an observable reduction in the Ir oxidation state as a result of charge donation from ATO to IrO x .…”

“…Tin based oxide supports (SnO 2 , doped‐SnO 2 : antimony doped tin oxide, indium doped tin oxide, fluorine doped tin oxide etc. ), [27–42] titanium‐based oxide supports (TiO x , Ti n O (2‐n) , doped titanium oxide), [37,43–50] Ta 2 O 5 , [51] Nb‐based oxides, [52–55] are by far the most popular metal oxide supports due to their stability under oxidative conditions, and the tunable electrical conductivity for some, and possible metal‐support interactions [6] . For instance, Oh et al.…”

Modulation for RuO2/TiO2 via Simple Synthesis to Enhance the Acidic Oxygen Evolution Reaction

“…Hence, extensive efforts to modify RuO 2 electrocatalysts have been given to improve the activity and stability, as well as reduce the cost. Dispersing active particles on stable metal oxide supports like doped tin oxides, , manganese oxides, , and tricobalt tetroxides , is a promising way to approach the above needs for OER electrocatalysts, due to good corrosion resistance for support and electronic coupling interactions with surface-supported noble metals . However, most of the inert supports are synthesized in laboratories by corresponding precursors to introduce doping elements or modify surface morphology, which make the whole process more complicated.…”