In situ synthesis of poly(ionic liquid)–Pt nanoparticle composite in glass capillary for the electrocatalytic reduction of oxygen

A novel approach for in situ synthesizing poly(ionic liquid)–Pt nanoparticle (PIL–Pt) composite in a glass capillary for fabricating filling-type electrode is reported in this work. XRD and TEM were used to characterize the as-synthesized PIL–Pt composite. Because of the modification of poly(ionic liquid)s (PILs), the PIL–Pt composite can not only be dispersed well to form a homogeneous suspension of Pt nanoparticles, but also be synthesized directly in a glass capillary with a tip radius ranging from 250 nm to 2.5 µm. By simple heating at 130 °C, the PIL–Pt composite capillary electrode was fabricated under mild conditions. With the advantages of both PILs and glass capillary, a PIL–Pt capillary electrode can provide a favourable microenvironment for the encapsulated Pt nanoparticles and promote the mass transfer rate; thus, showing a high electrocatalytic activity and stability for an oxygen reduction reaction (ORR). The present study provided a novel method for the development of high performance electrocatalysts based on the construction of PIL–Pt composite in a glass capillary for fuel cell or electrochemical sensors.