High-Performance Proton-Conducting Fuel Cell with B-Site-Deficient Perovskites for All Cell Components

Abstract

Proton-conducting fuel cells (PCFCs) with a perovskite-type proton-conducting electrolyte show many advantages over conventional oxygen-ion-conducting ceramic fuel cells. Both electrode catalytic activity and electrolyte conductivity determine the performance of PCFCs. Cation non-stoichiometry has a great influence on the catalytic activity and conductivity of perovskite oxides. Here, we propose a PCFC with B-site-cation-deficient perovskites (BCDPs) for all cell components, including cathode, electrolyte, and anode. More specifically, a cell with Ba­(Co0.4Fe0.4Zr0.1Y0.1)0.95O3−δ (BCFZY-0.95) cathode, Ba­(Zr0.1Ce0.7Y0.1Yb0.1)0.95O3−δ (BZCYYb-0.95) electrolyte, and Ni–BZCYYb-0.95 anode is fabricated and tested for power generation. Electrochemical impedance spectroscopy in combination with the distribution of relaxation times verify the superior oxygen reduction reaction activity of the BCFZY-0.95 cathode compared to BaCo0.4Fe0.4Zr0.1Y0.1O3−δ and higher proton conductivity of BZCYYb-0.95 than BaZr0.1Ce0.7Y0.1Yb0.1O3−δ. At 650 °C, a BCDP cell with a thin-film electrolyte shows a high-power density of 840 mW cm–2. The cell is stably operated within the test period of 400 h of stability at 550 °C.

Nanocomposites: A New Opportunity for Developing Highly Active and Durable Bifunctional Air Electrodes for Reversible Protonic Ceramic Cells

“…The DRT of SF and SF98 composites in 3 vol% H 2 O‐Air (Figure 3e) were also compared. The significantly lower resistances of P3 and P2 for the SF98 composite in comparison to SF single‐phase suggest that, consistent with literature, [ 35 ] the RP‐SF phase promotes steam/O 2 diffusion as well as surface exchange and ion transfer. Surprisingly, we noted that the values of P2 and P3 for SCFN composite are lower than those of the SF98 composite.…”

“…[ 34 ] It is also understood that intermediate‐frequency (P2) corresponds to the surface exchange and bulk diffusion and that low‐frequency (P3) indicates gas diffusion (steam and O 2 ). [ 30,35,36 ] The area under a specific peak represents the resistance of the corresponding process. The P3 of SCFN drops sharply after steam is introduced (Figure 3d), implying decreased resistance (P3).…”

Building Ruddlesden–Popper and Single Perovskite Nanocomposites: A New Strategy to Develop High‐Performance Cathode for Protonic Ceramic Fuel Cells

“…Since the cathodic performance decisively determines the electrode polarization resistance, the search for high‐performance cathodes that performs well in ILT‐PCFCs has attracted more and more attention. [ 15–20 ]…”

High-Performance-Based Perovskite-Supported Nanocomposite for the Development of Green Energy Device Applications: An Overview

“…Yavari et al synthesized a PtNP–CNTs–NdFeO3NPs–CH nanocomposite in a direct methanol fuel cell (DMFC) with perovskite oxide, which exposed the multifunctional energy harvesting using a single engineered material [ 71 ]. He et al reported the development of proton-conducting fuel cells (PCFCs) with a perovskite-type proton-conducting electrolyte P with B-site cation-deficient perovskites (BCDPs) for anode composite of the cell-component-emphasized cations, which accommodated between the inorganic layers, yielding a richer platform for chemical tuning [ 72 ]. Shao et al demonstrated a single-layer fuel-cell design that offers an attractive possibility to diminish the reduction of power density by limiting oxygen mass transfer to the cathode and increasing the cathode-to-anode area proportion with implementation of a perovskite oxide [ 73 ].…”