Park, Yoonsu, et al. International Journal of Hydrogen Energy 45.57 (2020): 32780-32788.
Iron phosphide (FeP) has garnered significant attention as a hydrogen evolution reaction (HER) catalyst due to its cost-effectiveness, high catalytic activity, and stability across a wide pH range. However, a systematic analysis of FeP nanoparticles (NPs) is still required to enhance their catalytic performance. Herein, we report the synthesis of FeP NPs through phosphidation reactions using various phosphorous sources (TOP, trioctylphosphine; TPP, triphenylphosphite; TEAP, tri(diethylamino)phosphine; and TBP, tri-n-butylphosphine).
Synthesis of FeP Nanoparticles
For the phosphidation of iron NPs, 7 mL of squalane and 3 mL of the phosphorous source (TOP, TPP, TEAP, or TBP) were added to a 50 mL three-neck flask. The solution was degassed at 120 °C for 1 hour to remove impurities. Subsequently, it was heated to 360 °C and maintained at this temperature for 1 hour to activate the phosphidation process. At 360 °C, the solutions containing TPP and TEAP turned opaque brown, while those containing TOP and TBP remained clear light yellow. After the activation process, 10 mL of ODE/OLA solution containing Fe NPs was quickly injected into the phosphorous solution, and the temperature was then lowered to 300 °C and maintained. During the phosphidation reaction, NP samples were collected at intervals of 30 minutes, 1.5 hours, 3 hours, and 4 hours using a glass syringe for subsequent electrochemical and material analyses. All samples were washed by adding ethanol/chloroform and centrifuged at 6000 rpm for 5 minutes. This washing process was repeated three times. All NP samples were stored in chloroform.