화학공학소재연구정보센터
Journal of Colloid and Interface Science, Vol.544, 178-187, 2019
Tunable engineering hollow carbon nanomaterial served as an excellent catalyst for oxygen reduction reaction and hydrogen evolution reaction
Fe and N functionalized hollow carbon spheres (Fe/N-HCS) with hierarchically porous structure are constructed. Remarkably, it is discovered that the pyrolysis temperature effects the chemical composition intensively. At 800 degrees C, only graphitic-N and oxidized-N are formed for all as-prepared samples. The surface area and pores can be precisely tuned, the surface area of all Fe/N-HCS samples is more than 500 m(2) g(-1) benefiting from the porous hollow structure. Thus, the optimized Fe/N-HCS exhibits excellent oxygen reduction reaction performance in term of onset potential (1.00 V vs. RHE), half-wave potential (0.87 V vs. RHE), good stability as well as methanol tolerance for oxygen reduction reaction, even surpassing the Pt in alkaline condition and more competitive in acidic condition: Furthermore, the optimized Fe/N-HCS displays better hydrogen evolution reaction activity in acidic condition with onset overpotential of 40 mV and overpotential to deliver 10 mA cm(-2) at 170 mV, indicating better active. It is found that Fe/N-HCS improve the hydrogen evolution reaction activity after electrodeposition trace quantity of Pt, which shows 170 mV of overpotential to deliver 100 mA cm(-2). X-ray photoelectron spectroscopy result indicates the loading of Pt is roughly 0.11 at%, thus, the improved performance is basically due to the synergistic effect between Pt and Fe/N-HCS. (C) 2019 Elsevier Inc. All rights reserved.