Magneli phase Ti n O2n − 1 as corrosion-resistant PEM fuel cell catalyst support

Abstract

Magneli phase titanium suboxide, Ti n O 2n − 1 , with Brunauer-Emmett-Teller surface area up to 25 m 2 g −1 was prepared using the heat treatment of titanium oxide (rutile) mixed with polyvinyl alcohol in ratios from 1:3 to 3:1. XRD patterns showed Ti 4 O 7 as the major phase formed during the heat treatment process. The Ti n O 2n − 1 showed excellent electrochemical stability in the potential range of −0.25 to 2.75 V vs. standard hydrogen electrode. The Ti n O 2n − 1 was employed as a polymer electrolyte membrane fuel cell catalyst support to prepare 20 wt% platinum (Pt)/Ti n O 2n − 1 catalyst. A fuel cell membrane electrode assembly was fabricated using the 20 wt% Pt/Ti n O 2n − 1 catalyst, and its performance was evaluated using H 2 /O 2 at 80°C. A current density of 0.125 A cm −2 at 0.6 V was obtained at 80°C.

Enhancement of Catalytic Activity and Durability of Pt Nanoparticle through Strong Chemical Interaction with Electrically Conductive Support of Magnéli Phase Titanium Oxide

“…The calculated initial ECSA of Pt/MPTO samples is relatively low than Pt/C regardless of particle size. It is due to the low electrical conductivity of MPTO and is consistent with the results reported in previous literature [ 13 , 72 , 73 ]. The linear sweep voltammograms (LSVs) on Pt/MPTO and Pt/C, recorded in the anodic sweep mode in an O 2 -saturated 0.1 M HClO 4 solution at 1600 rpm.…”

“…To alleviate the negative effects of the amorphous carbon deterioration, corrosion-resistant carbon supports; CNT [ 7 , 8 ], CNF [ 9 ], and graphene [ 10 , 11 ], heteroatom doped carbon [ 12 ] and also metal oxide supports have been introduced in the literature [ 13 , 14 , 15 , 16 , 17 , 18 ]. Among varied metal oxides [ 19 , 20 , 21 ], TiO 2 draws prominent attention because of high chemical-durability and good corrosion-resistance under PEFCs operation.…”

A highly active nanostructured metallic oxide cathode for aprotic Li–O2batteries

“…17,18 Magnéli titanates have been considered as a potential conductive support in many electrochemical systems. [19][20][21][22] This owes to their high conductivity and chemical stability even under highly aggressive conditions. [21][22][23][24] They combine the high conductivity of metals 25 and the corrosion resistance of ceramics.…”

“…[19][20][21][22] This owes to their high conductivity and chemical stability even under highly aggressive conditions. [21][22][23][24] They combine the high conductivity of metals 25 and the corrosion resistance of ceramics. 22 Also, as the Magnéli oxide materials are only mildly reduced vis a vis the parent oxide, they are expected to be resistant to nucleophilic attack by O 2 À /O 2 2À anions and to be promising candidates for good anodic stability in the OER potential window of interest.…”

Highly conductive nano-sized Magnéli phases titanium oxide (TiOx)

“…According to the titanium-oxygen system phase diagram, this is the simplest pathway to obtain Magnéli phase TiO x . Commonly employed reducing agents include carbon 6, 7 , zirconium 8 , and hydrogen (H 2 ) or ammonia 9, 10 . These reduction methods have been proven to effectively synthesize single Magnéli phase TiO x , often Ti 4 O 7 which has the highest conductivity among all Magnéli phases 11 .…”