Platinum nanoparticles decorated carbon nanofiber hybrids as highly active electrocatalysts for polymer electrolyte membrane fuel cells

Abstract

Increasing the efficiency of electrocatalyst is the key demand for the polymer electrolyte membrane fuel cells (PEMFC). To address the activity and performance challenges of commercial electrocatalyst, Pt/C, we introduce a new hybrid catalyst support for Pt nanoparticles. In this regard, combining or mixing specific type of carbon-based supports is a feasible strategy to increase catalyst utilization and performance. In the current study, Pt nanoparticles (NPs) were decorated on a new hybrid network, comprising of carbon nanofiber (CNF) and carbon black (CB), by means of a facile and efficient microwave (MW) assisted reduction method. All synthesized electrocatalysts were characterized to elucidate chemical and morphological structures. Then, the hybrid electrocatalysts were utilized as hydrogen oxidation reaction (HOR) and oxygen reduction reaction (ORR) electrocatalysts and their electrocatalytic activities were investigated by using cyclic voltammetry (CV) and linear sweep voltammetry (LSV), respectively. We found that the hybridization of CNF with CB substantially improved not only the electrocatalytic activity but also the fuel cell performance, which can be attributed to a consecutive conductive network, in which CB acts as a spacer, and synergistic effects between the CNF and CB. The hybrid electrocatalyst (Pt/CNF-CB with 50:50 wt%) showed a superior activity toward HOR and ORR while also offering exceptional fuel cell performance. That hybrid possessed the highest electrochemically active surface area (ECSA) compared with Pt/CNF and Pt/CB. In addition, the mass activity (at 0.80 V vs RHE) of the Pt/CNF-CB (50:50 wt%) is about 3.3 and 3.5 times higher than that of Pt/CNF and Pt/CB, respectively. Furthermore, that hybrid electrocatalyst exhibited enhanced fuel cell performance with 907 mW. cm −1 maximum power density. This work demonstrated that the CNF-CB supported Pt nanoparticles as electrocatalysts are extremely promising for fuel cell reactions.

Pulsed‐UV illumination on graphene oxide: A new strategy in photocatalytic synthesis of electrocatalysts to control the structural and electrochemical properties

“…In previous studies in which the deposition method and/or the carbon‐based materials were different the resulted mass activities have been reported to be in the range of 0.063 to 0.272 A mg −1. 7,40 The charge transfer current coming from the kinetically controlled region, for the not‐modified sample, is higher than the modified one. This could be because of graphene's different structures coming from oxygen functional groups which were shown from XPS spectra of C 1s in Figures 6C,C.…”

“…Yet, the vulnerability of the conventional carbon black to harsh environments and corrosion increases the chance of detachment and agglomeration of Pt 6 . Consequently, a support material that could be highly stable and conductive is desirable 7 …”

Development of a Bifunctional Ti-Based Gas Diffusion Electrode for ORR and OER by One- and Two-Step Pt-Ir Electrodeposition

“…The ECSA values obtained for the Pt/Ti_CPD_PED electrodes were six to ten times lower than the ECSA for state-of-the-art commercial Pt/C catalysts which range from 60 to 110 m echem. 2 g −1 [ 54 ]. Furthermore, compared to the 83.1 m echem.…”

“…2 g −1 to 80 m echem. 2 g −1 , the 2-PtIr electrode was outperformed [ 39 , 54 ]. Moreover, for nanocomposite PtIrO 2 /C catalysts prepared via chemical synthesis, ECSAs of 77 m echem.…”

Electrodeposited NiRh alloy as an efficient low‐precious metal catalyst for alkaline hydrogen oxidation reaction

“…[1][2][3] However, their high cost due to the exclusive use of expensive Pt and Pt-based catalysts 3,4 is still considered an obstacle to commercialization, despite the efforts to increase the mass activity of Pt. 5,6 As a promising alternative to PEMFCs, anion exchange membrane fuel cells (AEMFCs) have been receiving increasing attention mainly because they comprise non-precious metals and alloy catalysts in alkaline media with relatively high activity and stability. 7,8 Another benefit of using alkaline media, compared with acidic media, is the enhanced kinetics of the oxygen reduction reaction (ORR).…”