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Developing a cost‐effective electrocatalyst toward ethanol electrochemical oxidation plays a vital role in large‐scale applications of direct ethanol fuel cells (DEFCs). Herein, a rutile Ti0.9Ir0.1O2‐supported low Pt‐loading catalyst is fabricated using a surfactant‐free one‐pot chemical reduction route at room temperature that not only reduces the amount of the Pt loading but also significantly enhances the CO antipoisoning and electrochemical stability toward ethanol electrochemical oxidation compared with the conventional carbon‐supported Pt electrocatalyst. The rutile Ti0.9Ir0.1O2 nanosupport with rod‐like morphology is first prepared via a one‐pot hydrothermal route, and then 15.5 wt% Pt nanoparticles with small size (≈3 nm) are anchored on it by the surfactant‐free chemical reduction process. For ethanol electrochemical oxidation, the rutile Ti0.9Ir0.1O2‐supported Pt catalyst shows a moderate current density (≈13.74 mA cm−2), which is comparable with the 20 wt% Pt/C electrocatalyst, despite its low loading (15.5 wt%). In addition, the rutile Ti0.9Ir0.1O2‐supported low Pt‐loading electrocatalyst demonstrates low onset potential (0.45 V vs normal hydrogen electrode [NHE]), superior CO‐tolerance, and impressive electrochemical stability compared with the carbon‐supported Pt catalyst. These enhancements are ascribable to the inherent durability of the rutile TiO2 nanostructure and the synergistic effect between Pt and Ti0.9Ir0.1O2 nanosupport. [ABSTRACT FROM AUTHOR]

The novel nanostructured Ti 0.9 Ir 0.1 O 2 acting as a potential catalyst support for Pt in fuel cell applications was easily synthesized by means of a facile and simple low-temperature hydrothermal process without using any surfactants and further heat treatment. Interestingly, even in low iridium doping concentration, the Ti 0.9 Ir 0.1 O 2 support possessed the high electronic conductivity of 0.016 S/cm, which was ∼105 times as high as pure TiO 2 (4.15 × 10−7 S/cm), suggesting the efficient doping of iridium into TiO 2 lattice. Furthermore, the modified chemical reduction route utilized to prepare the 20 wt % Pt/Ti 0.9 Ir 0.1 O 2 electrocatalyst exhibited the good anchoring and uniform distribution of Pt nanoparticles (NPs) (∼3 nm) over Ti 0.9 Ir 0.1 O 2 surface and thus eventually resulted in the high electrochemical surface area (∼85.08 m2/gPt) compared to that of the commercial 20 wt % Pt/C (E-TEK) catalyst (∼69.21 m2/gPt). The cyclic voltammetry results in the methanol media revealed that the 20 wt % Pt/Ti 0.9 Ir 0.1 O 2 displayed the superior electrocatalytic activity compared to the 20 wt % Pt/C (E-TEK) catalyst towards the methanol electro-oxidation. For instance, the 20 wt % Pt/Ti 0.9 Ir 0.1 O 2 catalyst possessed the higher oxidation current density (∼28.8 mA/cm2), the lower onset potential (∼0.12 V) and the higher I f /I b ratio in comparison with the commercial 20 wt % Pt/C (E-TEK) catalysts. It is worth noting that the chronoamperometry results also indicated that the 20 wt % Pt/Ti 0.9 Ir 0.1 O 2 exhibited higher durability than the commercial 20 wt % Pt/C (E-TEK) catalyst. Beside introducing novel Ti 0.9 Ir 0.1 O 2 material, these results also offer a pathway of exploring the low dopants content of Ti x Ir 1-x O 2 material to serve as a good catalyst support for many fuel cell applications. • A facile green synthetic route for the preparation of the novel Ti 0.9 Ir 0.1 O 2. • The Ti 0.9 Ir 0.1 O 2 possessed high electronic conductivity with the low doping concentration. • Pt/Ti 0.9 Ir 0.1 O 2 has low onset potential for methanol oxidation reaction. • Pt/Ti 0.9 Ir 0.1 O 2 demonstrates high activity and durability for methanol oxidation. [ABSTRACT FROM AUTHOR]

Abstract Late transition metal doped TiO 2 has been exploited for generating efficient catalyst support by enhancing electrical conductivity and modifying properties of TiO 2. The Ti 0·7 Ir 0·3 O 2 nanorod (NRs), a novel catalyst support for Pt nanoparticles, was prepared for the first time via single-step hydrothermal process at low temperature using IrCl 3 ·3H 2 O and TiCl 4 as starting materials. We found that the Ti 0·7 Ir 0·3 O 2 NRs with 70–80 nm in length and 25–30 nm in width is successful prepared at 210 °C for 12 h without utilizing surfactants or stabilizers. In addition, the Ti 0·7 Ir 0·3 O 2 NRs was presented principally as a single-phase solid with the TiO 2 is in the rutile form with high crystallinity without using further treatment after synthesis. More importantly, we found that the Ti 0·7 Ir 0·3 O 2 NRs possesses high electrical conductivity (0.028 S cm−1) dealing the intrinsically non-conducted drawback of TiO 2. The Pt nanoparticles were then deposited on the support of Ti 0·7 Ir 0·3 O 2 NRs via chemical reduction method. The properties of 20 wt % Pt/Ti 0·7 Ir 0·3 O 2 NRs electrocatalyst were characterized by X-ray diffraction (XRD), Transmission electron microscopy (TEM), the cyclic voltammetry (CV). The uniformly distributed small Pt nanoparticles (3–4 nm diameter) were well adhered to the Ti 0·7 Ir 0·3 O 2 NRs. The electrochemically active surface area (ECSA) of 20 wt % Pt/Ti 0·7 Ir 0·3 O 2 NRs was higher than that of the commercial 20 wt % Pt/C (E-TEK) due to the small size and good dispersion of Pt nanoparticles on the surface of Ti 0·7 Ir 0·3 O 2 NRs. Moreover, the ECSA value of the Pt/Ti 0·7 Ir 0·3 O 2 NRs retained up to 88% after 2000 cycles of cyclic voltammetry, suggesting the high stability of catalyst resulted from strong metal support interaction (SMSI) of Titania-based materials with the noble metals. More importantly, the onset potential of Pt/Ti 0·7 Ir 0·3 O 2 NRs catalyst towards oxygen reduction reaction is more positive (∼80 mV) compared to commercial Pt/C, indicating the high catalytic activity of the Pt/Ti 0·7 Ir 0·3 O 2 NRs catalyst. The results of this research suggested that novel Ti 0·7 Ir 0·3 O 2 NRs could be applied as promising robust non-carbon support for Pt. This research also creates a preliminary step for investigating systematically promising Iridium doped Titania materials. Graphical abstract Image 1 Highlights • Novel nanorod Ti 0·7 Ir 0·3 O 2 was synthesized via one step hydrothermal process. • Iridium doping induces the electrical conductivity of TiO 2 ∼ 105 times. • Pt/Ti 0·7 Ir 0·3 O 2 NRs catalyst possesses high ECSA and profoundly stable after 2000 CV cycles. • Pt/Ti 0·7 Ir 0·3 O 2 NRs has low overpotential for oxygen reduction reactions. [ABSTRACT FROM AUTHOR]