Research Progress on Proton-conducting Solid Oxide Fuel Cells with Hydrogen-containing Fuel

doi:10.15541/jim20250132

Abstract

Abstract:

Driven by global energy transition and carbon neutrality goals, proton-conducting solid oxide fuel cells (P-SOFCs) have become a research hotspot in clean energy technology due to their advantages of efficient medium-to-low temperature power generation (400-600 ℃), excellent fuel compatibility, and high energy conversion efficiency. This review analyzes the development prospects of hydrogen-containing fuel P-SOFCs. Addressing key technological bottlenecks, this review focuses on three core dimensions including material design, reaction mechanisms, and characterization techniques to summarize research progress and technical challenges in hydrocarbon-fueled and ammonia-fueled P-SOFC systems. For hydrocarbon-fueled P-SOFCs, the carbon deposition issue is thoroughly examined. Their formation mechanisms, characterization methods and influencing factors on carbon deposition are discussed in depth. Advanced improvement strategies are highlighted, including modification of reforming catalysts, optimization of proton-conducting electrolytes, and novel design of electrodes. Regarding direct ammonia fuel cells (DAFCs), challenges related to insufficient anode durability are addressed. Critical influencing factors are identified as catalyst activity, support types, nitridation corrosion mechanisms, hydrogen partial pressure, ammonia flow rate, and anode microstructure. Based on cutting-edge research, novel improvement strategies, such as anode modification, optimization of anode catalytic layers and innovative cell structure designs, are summarized. This review outlines future development directions to advance the commercialization of hydrogen-containing fuel P-SOFCs.

Key words: solid oxide fuel cell, proton conductor, hydrocarbon fuel, ammonia, review

CLC Number:

TK91

XUE Zixuan, YIN Chaofan, YAO Yuechao, WANG Yanmin, SUN Yueyue, LIU Zhengrong, ZHOU Yucun, ZHOU Jun, WU Kai. Research Progress on Proton-conducting Solid Oxide Fuel Cells with Hydrogen-containing Fuel[J]. Journal of Inorganic Materials, 2025, 40(12): 1324-1340.

Figures/Tables 10

Fig. 1 Comparison of P-SOFCs and O-SOFCs[16] (a) Performances comparison of P-SOFCs and O-SOFCs; (b) Schematic illustration of ionic transport mechanism of O-SOFCs and P-SOFCs

Table 1 Hydrogen cost in different hydrogen production pathways[25]

Type	Hydrogen production technology	Cost/ (RMB·kg^-1)
Grey hydrogen	Coal gasification	7-11
Grey hydrogen	Steam methane reforming (SMR)	9-18
Blue hydrogen	Coal gasification with carbon capture, utilization and storage	9-20
	SMR with carbon capture storage	13-24
	Carbon capture storage	2-9
Green hydrogen	Water electrolysis	20-62

Fig. 2 P-SOFCs performance across a range of fuels[33] (a) Current density versus voltage (j-V) and current density versus power density (j-P) curves of P-SOFCs under a range of fuels; (b) Peak power densities, lifetime and degradation rates of P-SOFCs on 12 different fuel streams at 600 ℃

Fig. 3 Schematics of single chamber SOFCs[39] (a) Single chamber SOFCs with coplanar electrodes; (b) Single chamber SOFCs with fully porous electrolyte in flow-by configuration; (c) Single chamber SOFCs with fully porous electrolyte in flow-through configuration

Fig. 4 Common characterization methods for carbon deposition on SOFCs anodes[54,56,59,61,67] (a) SEM images and EDS carbon elemental mappings of the spent cell. (A-I, A-II and A-III: spent cell without catalyst; B-I, B-II and B-III: spent cell with catalyst)[54]; (b) XRD patterns of different SOFCs anode materials (A: GDC; B: Au-Mo-Ni/GDC; C: Ni/GDC; D: Au-Ni/GDC)[56]; (c) HR-TEM images of formation of the graphitic layer in NiO (A) and MgO-modified NiO (B)[59]; (d) TPO results of the carbon deposits (A: weight loss curves and derivative plots; B: yields of different types of carbons deposits at different pyrolysis temperatures)[61]; (e) Time-resolved normal Raman and SERS analysis of coking and carbon removal on nickel surface (carbon deposition on (A) blank Ni and (B) Ag@SiO2 loaded Ni, and (C) integrated intensity of the carbon D-band; removal of carbon deposition on (D) blank Ni and (E) Ag@SiO2 loaded Ni, and (F) integrated intensity of the carbon D-band)[67]

Fig. 5 Physicochemical properties of BaZr0.4Ce0.4Y0.1Yb0.1O3-δ electrolyte[76] (a) XRD patterns before and after exposure to 100% CO2 at 500 ℃; (b) Thermogravimetric analysis profile on exposure to 60% CO2 (balance N2) at 500 ℃; (c) Conductivity under humidified N2 atmosphere (pH2O=3.1×103 Pa) compared to that of BaZr0.8Y0.2O3-δ (BZY20) sintered under similar conditions; (d) SEM image of the as-sintered surface morphology

Fig. 6 Ammonia conversions at 550 ℃ for ammonia decompositions on nickel-based catalysts with different supports[93]

Fig. 7 Electrochemical impedance spectra at OCV and 600 ℃ of DA-SOFCs supplied with various fuels[99]

Fig. 8 Electrochemical performance and durability of SFMC-modified P-SOFCs[106] (a) Current density versus voltage (j-V) and current density versus power density (j-P) curves of the cell with the SFMC-modiﬁed Ni-BZCYYb anode at 600-700 ℃ using wet H2 and dry NH3 as fuels and ambient air as an oxidant; (b) Comparisons on the PPD of the cells with the bare Ni-BZCYYb and SFMC active catalytic layer (ACL) modified Ni-BZCYYb anodes at 600-700 ℃ in wet H2 and dry NH3; (c) Operation stabilities of the single cells with the bare Ni-BZCYYb and SFMC-modiﬁed Ni-BZCYYb anodes at 650 ℃ under a current density of 0.5 A/cm2 using dry NH3 as fuel

Fig. 9 Novel structural design schemes for DA-SOFCs[109-110] (a) Test schematic diagram of tubular catalyst embedded P-SOFCs[109]; (b) Illustration of the cell anode preparation using the grid-assisted phase transformation method[110]

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