1 2 tetradecanediol

Pt nanoparticle synthesis was performed according to the protocol reported by Liu et al.17 Briefly, the synthesis is initiated by dissolving 0.25 mmol Pt(acac)₂ (Acros Organic) and 1.50 mmol 1,2-tetradecanediol (90 %, Sigma Aldrich) in 20 mL dioctyl ether (99 %, Sigma Aldrich) under Ar atmosphere, followed by heating to 110 °C at a rate of 5 °C min⁻¹ under stirring. OA (4.2 mmol; 70 %, Sigma Aldrich) was added drop-wise to the clear, yellow solution over the course of 2 min. The solution was further heated to 215 °C, and left to stir for 1 h before cooling to 50 °C. The dark brown particle dispersion was added to a glass vial containing 10 mL MeOH, and sonicated for 5 min. Nanoparticles were precipitated by centrifugation, and re-dispersed in hexane. All high-purity reagents were used as received. To prepare the carbon-supported catalyst (Pt/C), Vulcan XC-72R (Cabot Corp) was added to a colloidal Pt nanoparticle dispersion, and sonicated for 2 h. The solution turned clear, indicating complete deposition of nanoparticles onto the carbon support. Hexane was removed under a stream of argon to yield the dry Pt/C catalyst powder.
A variety of chemical and thermal pre-treatment protocols were investigated for the as-prepared Pt/C nanostructures, as summarised in Table 1 and Table 2. A fixed amount of the Pt/C catalyst (5 mg) was used for each chemical pre-treatment.