fig1

Figure 1. Schematic diagram of (A) PEMFC, reproduced with permission from Tellez-Cruz et al.^[11] Copyright 2021 MDPI; (B) AFC, reproduced with permission from Das et al.^[12] Copyright 2022 MDPI; (C) PAFC, reproduced with permission from Petrovic et al.^[13] Copyright 2020 IEEE; (D) SOFC and (E) P-SOFC, reproduced with permission from Jang et al.^[14] Copyright 2024 American Chemical Society. PEMFC: Proton exchange membrane fuel cell; AFC: alkaline fuel cell; PAFC: phosphoric acid fuel cell; P-SOFC: Protonic solid oxide fuel cell.