Direct utilization of methanol on impregnated Ni/YSZ and Ni-Zr0.35Ce0.65O2/YSZ anodes for solid oxide fuel cells

Some of the limits on fuel cell development include the issues of hydrogen availability and storage. Methanol has many advantages as an alternative fuel for fuel cells but depending on the anode composition, the formation of carbon may be a problem. In this paper, the direct utilization of methanol in solid oxide fuel cells with impregnated Ni/YSZ and Ni-Zr_0.35Ce_0.65O_2−δ (ZDC)/YSZ anodes was investigated at 1073 K. Performance and stability of these anodes, as measured by steady-state polarization and electrochemical impedance spectroscopy, were improved by the presence of ZDC; although, the deposition of carbon, as detected by scanning electron microscopy and temperature-programmed oxidation analysis, was not entirely avoided. The impact of the carbon, however, was different depending on the anode. That is, carbon formation caused the delamination of impregnated Ni/YSZ anodes, while the structural integrity of Ni-ZDC/YSZ anodes was maintained and the cell performance was not negatively impacted. Increasing the fuel utilization decreased coking, as predicted by equilibrium calculations.     

Cobalt-impregnated La0.75Sr0.25Cr0.5Mn0.5O3−δ anodes for solid oxide fuel cells

In this study, we will report our investigation for La_0.75Sr_0.25Cr_0.5Mn_0.5O_3−δ (LSCrM) based anodes impregnated with solutions of cobalt (Co) nitrate. A YSZ supported SOFC with pure LSCrM anode and La_0.7Sr_0.3MnO₃ (LSM) cathode exhibits the maximum power density (P_max) of 58.7 and 5.2 mW cm⁻² at 850 °C in dry H₂ and dry CH₄. After the modification of anode with Co nitrate, the P_max reaches 196.2 mW cm⁻² in dry H₂ and 28.5 mW cm⁻² in dry CH₄, about 3.34 times and 5.48 times increase, respectively. These results indicate that Co is also a potential catalyst for LSCrM anode. Moreover, the effect of impregnation amount of catalyst on the cell performance is also evaluated in this study.     

Investigation of Ni2+-doped ceria nanorods as the anode catalysts for reduced-temperature solid oxide fuel cells

Tailoring the surface chemistry of oxides has been widely used to adjust their catalytic behavior in the energy conversion and storage devices. Herein, nanorods of Ni²⁺-doped ceria (Ce_1-xNi_xO_2-δ, x = 0, 0.05, 0.1, 0.15) are synthesized via a modified hydrothermal method, and evaluated as the anode catalysts for reduced-temperature solid oxide fuel cells (SOFCs). X-Ray diffraction patterns of as-synthesized powders in air imply successful incorporation of Ni²⁺ into the fluorite lattice of ceria for x = 0.05 and 0.1, with a secondary phase of NiO observed for x = 0.15. Transmission electron microscopy (TEM) examination confirms a rod-like morphology with a diameter of 10–13 nm and a length of 55–105 nm. Exposure of these powders in H₂ at 600°C results in exsolution of some spherical Ni particles of 11 nm in diameter. Electrochemical measurements on both symmetrical anode fuel cells and functioning cathode-supported fuel cells show an order of the catalytic activity toward hydrogen oxidation - CeO_2-δ < Ce_0·95Ni_0·05O_2-δ < Ce_0·9Ni_0·1O_2-δ. The anode polarization resistances in 97% H₂ – 3% H₂O are 0.24, 0.31 and 0.37 Ω?cm² for Ce_0·9Ni_0·1O_2-δ, Ce_0·95Ni_0·05O_2-δ and CeO_2-δ at 600°C, respectively. Thin (La_0·9Sr_0.1) (Ga_0.8Mg_0.2)O_3-δ-electrolyte fuel cells with nanostructured SmBa_0.5Sr_0·5Co₂O_5+δ cathodes and Ce_0·9Ni_0·1O_2-δ anodes yield the highest power densities among the investigated series of anodes, e.g., 820 mW?cm^?2 in 97% H₂ – 3% H₂O and 598 mW?cm^?2 in 68% CH₃OH - 32% N₂. XPS analyses of reduced nanorods indicate that the highest catalytic activities of Ce_0·9Ni_0·1O_2-δ toward fuel oxidation reactions should be correlated to the presence of highly active Ni nanoparticles and increased surface active oxygen, as confirmed by substantially facilitated extraction of the lattice oxygen on the surface by H₂ in temperature-programmed reduction (TPR) measurements.     

BaZr0.1Ce0.7Y0.1Yb0.1O3−δ as highly active and carbon tolerant anode for direct hydrocarbon solid oxide fuel cells

BaZr_0.1Ce_0.7Y_0.1Yb_0.1O_3−δ (BZCYYb) perovskite is synthesized and examined as an alternative anode material for intermediate temperature solid oxide fuel cells (IT-SOFCs) based on direct hydrocarbon fuels, using polarization and electrochemical impedance spectroscopy techniques. Single-phased BZCYYb anode shows an excellent activity for both hydrogen and methane oxidation reactions, achieving a polarization resistance of 0.25 and 0.93 Ω cm², and overpotential of 20 and 202 mV at 100 mA cm⁻² and 750 °C in wet H₂ (3% H₂O/97% H₂) and wet CH₄ (3% H₂O/97% CH₄), respectively. The electrocatalytic activity of BZCYYb anodes is significantly higher than that of the (La,Sr)(Cr,Mn)O₃ anodes as reported in the literature. Furthermore, BZCYYb exhibits excellent resistance to carbon deposition. The present study demonstrates that BZCYYb perovskite is a promising alternative anode material for direct hydrocarbon fuels based SOFCs.     

Ni-doped Ba0.9Zr0.8Y0.2O3-δ as a methane dry reforming catalyst for direct CH4–CO2 solid oxide fuel cells

Fuel flexibility is one of the significant advantages of solid oxide fuel cells (SOFCs). The utilization of methane in SOFCs can not only reduce fuel costs, but also greatly expand its application scenarios, which is of great significance to the commercial development of SOFCs. However, when methane is directly used, Ni-based cermet anode suffers from coking, which seriously affects the durability of the cell. To alleviate the coking issue, a reforming layer outside the Ni-based anode-supporter was proposed in this study, and Ba_0.9(Zr_0.8Y_0.2)_1-xNi_xO_3-δ (BZYNi_x, x = 0.05, 0.1, 0.15 and 0.2) was used as reforming layer material. Among BZYNi_x catalysts, BZYNi_0.2 exhibited excellent catalytic activity toward dry reforming of methane, and methane conversion was as high as 85% at 750 °C. The excellent catalytic durability and coking-resistance of BZYNi_0.2 were also confirmed. When BZYNi_0.2 reforming layer was applied, the single cell fueled with CH₄–CO₂ fuel showed significantly improved electrochemical performance, durability and coking-resistance. The utilization of BZYNi_0.2 reforming layer provides guidance for solving the coking issue of SOFC cermet anodes when fueled with hydrocarbon.     

Effect of impregnation phases on the performance of Ni-based anodes for low temperature solid oxide fuel cells

Impregnated nanoparticles are very effective in improving the electrochemical performance of solid oxide fuel cell (SOFC) anodes possibly due to the extension of reaction sites and/or the enhancement of catalytic activity. In this work, samaria-doped ceria (SDC), pure ceria, samaria, and alumina oxides impregnated Ni-based anodes are fabricated to compare the site extending and the catalytic effects. Except for alumina, the impregnation of the other three nano-sized oxides could substantially enhance the performance of the anodes for the hydrogen oxidation reactions. Moreover, single cells with CeO₂ and Sm₂O₃ impregnated anodes could exhibit as great performance as those with SDC impregnated anodes. When the impregnation loading reached the optimal value, 1.7 mmol cm⁻³, these cells exhibit very high performance, with peak power densities around 750 mW cm⁻². The high performance of CeO₂ and Sm₂O₃ impregnated anodes demonstrates that the improved performance are mainly attributed to the significantly improved electrochemical activities of the anodes, but not to the extension of triple-phase-boundary, and wet impregnation is indeed an alternative and effective technique to introduce these nano-sized catalytic active oxides into the anode configuration of SOFCs to enhance cell performance, stability and reliability.     

Enhanced electrochemical performance and durability for direct CH4–CO2 solid oxide fuel cells with an on-cell reforming layer

Coking is a major issue with the traditional Ni-based anodes when directly oxidizing CH₄ in solid oxide fuel cells (SOFCs). Dry reforming to convert CH₄–CO₂ into CO–H₂ syngas before entering Ni-based anode may potentially be an effective and economical method to address the coking problem. Consequently, an on-cell reforming layer outside the Ni-based anode is expected to offer a unique solution for direct CH₄–CO₂ SOFCs without coking. In this study, Ni-GDC anode-supported cells with and without a Sr₂Co_0.4Fe_1.2Mo_0.4O_6-δ (SCFM) layer outside the anode support have been fabricated and evaluated using either H₂ or CH₄–CO₂ as fuel. Both types of cells show excellent electrochemical performance when H₂ is used as fuel, and the SCFM layer has negligible impact on the cell performance. When CH₄–CO₂ is used as fuel, however, the electrochemical performance and durability of the cells with the SCFM layer are much better than those without the SCFM layer outside the Ni-GDC anode, indicating that the SCFM layer can efficiently perform dry reforming. This unique on-cell dry reforming design enables direct CH₄–CO₂ solid oxide fuel cells and offers a very promising route for energy storage and conversion.     

In-situ exsolved NiFe alloy nanoparticles on Pr0.8Sr1.2(NiFe)O4-δ for direct hydrocarbon fuel solid oxide fuel cells

NiFe alloy (NFA) nanoparticles decorated Ruddlesden-Popper (RP) type layered perovskite structure Pr_0.8Sr_1.2(NiFe)O_4-δ (RP-PSNF) have been fabricated by in-situ reduction of cubic perovskite Pr_0.32Sr_0.48Ni_0.2Fe_0.8O_3-δ (P–PSNF) in H₂ at 800 °C. When used as the solid oxide fuel cell (SOFC) anode material, the RP-PSNF-NFA based ceramic anode demonstrates a comparable catalytic activity to Ni-based anode. The SOFC single cell with RP-PSNF-NFA-Gd_0.2Ce_0.8O_2−δ (GDC) anode exhibits a maximum power density of 983 and 770 mW cm⁻² in humidified H₂ and C₃H₈ at 800 °C, respectively. More importantly, the single cell shows a high durability at the current density of 250 mA cm⁻² in humidified C₃H₈ at 800 °C, demonstrating an excellent coking resistance. Overall, this work suggests that RP-PSNF-NFA is a promising anode for direct hydrocarbon fuel SOFCs.     

A new nickel–ceria composite for direct-methane solid oxide fuel cells

Various Ni–La_xCe_1−xO_y composites were synthesized and their catalytic activity, catalytic stability and carbon deposition properties for steam reforming of methane were investigated. Among the catalysts, Ni–La_0.1Ce_0.9O_y showed the highest catalytic performance and also the best coking resistance. The Ni–La_xCe_1−xO_y catalysts with a higher Ni content were further sintered at 1400 °C and investigated as anodes of solid oxide fuel cells for operating on methane fuel. The Ni–La_0.1Ce_0.9O_y anode presented the best catalytic activity and coking resistance in the various Ni–La_xCe_1−xO_y catalysts with different ceria contents. In addition, the Ni–La_0.1Ce_0.9O_y also showed improved coking resistance over a Ni–SDC cermet anode due to its improved surface acidity. A fuel cell with a Ni–La_0.1Ce_0.9O_y anode and a catalyst yielded a peak power density of 850 mW cm⁻² at 650 °C while operating on a CH₄–H₂O gas mixture, which was only slightly lower than that obtained while operating on hydrogen fuel. No obvious carbon deposition or nickel aggregation was observed on the Ni–La_0.1Ce_0.9O_y anode after the operation on methane. Such remarkable performances suggest that nickel and La-doped CeO₂ composites are attractive anodes for direct hydrocarbon SOFCs and might also be used as catalysts for the steam reforming of hydrocarbons.     

Effect of Sm0.2Ce0.8O1.9 on the carbon coking in Ni-based anodes for solid oxide fuel cells running on methane fuel

To directly use hydrocarbon fuel without a reforming process, a new microstructure for Ni/Sm_0.2Ce_0.8O_2−δ (Ni/SDC) anodes, in which the Ni surface of the anode is covered with a porous Sm_0.2Ce_0.8O_2−δ thin film, was investigated as an alternative to conventional Ni/YSZ anodes. The porous SDC thin layer was coated on the pores of the anode using the sol–gel coating method. The cell performance was improved by 20%–25% with the Ni/SDC anode relative to the cell performance with the Ni/YSZ anode due to the high ionic conductivity of the Ni/SDC anode and the increase of electrochemical reaction sites. For the SDC-coated Ni/SDC anode operating with methane fuel, no significant degradation of the cell performance was observed after 180 h due to the surface modification with the SDC film on the Ni surface, which opposes the severe degradation of the cell performance that was observed for the Ni/YSZ anode, which results from carbon deposition by methane cracking. Carbon was hardly detected in the SDC-coated Ni/SDC anode due to the catalytic oxidation of the deposited carbon on the SDC film as well as the electrochemical oxidation of methane in the triple-phase-boundary.     

Fabrication of an electrolyte-supported protonic ceramic fuel cell with nano-sized powders of Ni-composite anode

Composite anodes of nano-sized Ni and Ba(Zr_0.85Y_0.15)O_3-δ (BZY) were fabricated by infiltrating a single precursor solution of BZY and Ni into the BZY scaffold, and decreasing the calcination temperature to 1173 K. This decrease in the fabrication temperature of the Ni-cermet anode prevents the chemical reaction between the electrolyte and nickel, thus preventing a reduction in the conductivity of the electrolyte. By optimizing the amount of Ni in the Ni-cermet and infiltrating additional catalysts such as CeO₂ and Pd, the non-ohmic ASR of the Ni-cermet anode could be optimized. This resulted in a smaller non-ohmic ASR of anode than one that was fabricated by the conventional co-sintering method. Consequently, a high power density of 790 mW/cm² at 973 K can be obtained from electrolyte-supported cells.     

Ni infiltrated YSZ anode stabilization by inducing strong metal support interaction between nickel and titania in solid oxide fuel cell under accelerated testing

Sintering of Ni particles in Ni infiltrated porous YSZ anodes and decrease in triple phase boundary is the reason for performance loss in SOFC. In the present work, the idea of strong metal support interaction (SMSI) has been used to prevent the sintering of Ni particles by introducing TiO₂ as support with Ni catalyst. Electrical conductivity variation of porous YSZ matrix impregnated with Ni and Ni/TiO₂ have been investigated. Single button cells (anode supported) with and without TiO₂ impregnated Ni–YSZ anode were fabricated and characterized through current–voltage measurement at different loads. It is shown that the conductivity of porous Ni–YSZ anode and the performance of SOFC button cell with the same anode decreased with the increase in temperature and redox cycling at different time intervals. The power density of 12% Ni–YSZ anode was 116 mW/cm² and it increased to 180 mW/cm² for 12% Ni–4% TiO₂–YSZ based anodes at 800 °C. This increase was interpreted by strong attachment of Ni particles on TiO₂ preventing Ni coarsening during prolonged reduction in H₂ at 800 °C as observed by SEM. The power density increased with further increase in Ni loading and it reached to 400 mW/cm² for 16% Ni–4% TiO₂–YSZ based anodes. The performance increases with addition of TiO₂ support in Ni–YSZ based anodes corroborates with the impedance spectroscopy analyses.     

A symmetrical solid oxide fuel cell prepared by dry-pressing and impregnating methods

In this study, a simple and cost-effective dry-pressing method has been used to fabricate a symmetrical solid oxide fuel cell (SOFC) where the dense yttria-stabilized zirconia (YSZ) electrolyte film is sandwiched between two symmetrical porous YSZ layers in which La_0.75Sr_0.25Cr_0.5Mn_0.5O_3−δ (LSCM) based anode and cathode are incorporated using wet impregnation techniques. The maximum power densities (P_max) of a single cell with 32 wt.% LSCM impregnated YSZ anode and cathode reach 333 and 265 mW cm⁻² at 900 °C in dry H₂ and CH₄, respectively. The cell performance is further improved with additional impregnation of a small amount of Sm-doped CeO₂ (SDC) or Ni. When 6 wt.% Ni as catalyst is added to both the anode and cathode, P_max values of 559 and 547 mW cm⁻² can be achieved, which are better than with SDC. The effect of Ni on the cathode performance is also investigated by impedance spectra analysis.     

The catalytic effect of impregnated (La,Sr)(Ti,Mn)O3±δ with CeO2 and Pd as potential anode materials in high temperature solid oxide fuel cells

In this study, the catalytic effects and electrochemical properties of CeO₂ and Pd catalysts on La_0.4Sr_0.6Ti_0.8Mn_0.2O_3±δ (LSTM) were analyzed. The introduction of CeO₂ resulted in an advanced improvement of the polarization resistance values and hence in the performance. The optimized composition of CeO₂ with LSTM was observed with the addition of 20% of CeO₂ to LSTM-8mol % Y₂O₃ stabilized ZrO₂ (8YSZ). The power densities of this composite anode system measured at 800 and 850 °C were 196 and 302 mW cm⁻². When 1 wt% of Pd and 20 wt% CeO₂ were used as catalysts, the power density of the sample was 251 mW cm⁻² at 800 °C caused by the advanced catalytic activity towards H₂ oxidation. Significantly, the more CeO₂ was impregnated, the smaller the observed ohmic resistance (Rs) was, because the relatively high electrical conductivity from the CeO₂ compensated the lower conductivity property of the LSTM-8YSZ composite.     

Demonstrating the dual functionalities of CeO2–CuO composites in solid oxide fuel cells

Nowadays, lowering the operating temperature of solid oxide fuel cells (SOFCs) is a major challenge towards their widespread application. This has triggered extensive material studies involving the research for new electrolytes and electrodes. Among these works, it has been shown that CeO₂ is not only a promising basis of solid oxide electrolytes, but also capable of serving as a catalytic assistant in anode. In the present work, to develop new electrolytes and electrodes for SOFCs based on these features of CeO₂, a new type of functional composite is developed by introducing semiconductor CuO into CeO₂. The prepared composites with mole ratios of 7:3 (7CeO₂–3CuO) and 3:7 (3CeO₂–7CuO) are assessed as electrolyte and anode in fuel cells, respectively. The cell based on 7CeO₂–3CuO electrolyte reaches a power outputs of 845 mW cm^?2 at 550 °C, superior to that of pure CeO₂ electrolyte fuel cell, while an Ce_0.8Sm_0.2O_2-δ electrolyte SOFC with 3CeO₂–7CuO anode achieves high power density along with open circuit voltage of 1.05 V at 550 °C. In terms of polarization curve and AC impedance analysis, our investigation manifests the developed 7CeO₂–3CuO composite has good electrolyte capability with a hybrid H⁺/O^2? conductivity of 0.1–0.137 S cm^?1 at 500–550 °C, while the 3CeO₂–7CuO composite plays a competent anode role with considerable catalytic activity, indicative of the dual-functionalities of CeO₂–CuO in fuel cell. Furthermore, a bulk heterojunction effect based on CeO₂/CuO pn junction is proposed to interpret the suppressed electrons in 7CeO₂–3CuO electrolyte. Our study thus reveals the great potential of CeO₂–CuO to develop functional materials for SOFCs to enable low-temperature operation.     

Nanostructured palladium–La0.75Sr0.25Cr0.5Mn0.5O3/Y2O3–ZrO2 composite anodes for direct methane and ethanol solid oxide fuel cells

A palladium-impregnated La_0.75Sr_0.25Cr_0.5Mn_0.5O_3−δ/yttria-stabilized zirconia (LSCM/YSZ) composite anode is investigated for the direct utilization of methane and ethanol fuels in solid oxide fuel cells (SOFCs). Impregnation of Pd nanoparticles significantly enhances the electrocatalytic activity of LSCM/YSZ composite anodes for the methane and ethanol electrooxidation reaction. At 800 °C, the maximum power density is increased by two and eight times with methane and ethanol fuels, respectively, for a cell with the Pd-impregnated LSCM/YSZ composite anode, as compared with that using a pure LSCM/YSZ anode. No carbon deposition is observed during the reaction of methane and ethanol fuels on the Pd-impregnated LSCM/YSZ composite anode. The results show the promises of nanostructured Pd-impregnated LSCM/YSZ composites as effective anodes for direct methane and ethanol SOFCs.     

Methane internal steam reforming in solid oxide fuel cells at intermediate temperatures

The internal steam reforming of methane (CH₄) on conventional solid oxide fuel cell (SOFC) anode (nickel-yttria stabilized zirconia or Ni-YSZ) offers significant advantages compared to the external reforming process. However, the technology is currently facing some major issues such as coking and oxidation of anode during operation. Here we report a low-temperature sinterable catalyst, Ce_0·77Ni_0·2Mn_0·03O_2-δ (CNMnO), applied on top of Ni-YSZ to perform the steam reforming reaction. A single cell with CNMnO/Ni-YSZ/YSZ/GDC/LSC configuration produces a peak power density of 492 mW cm^?2 in wet hydrogen and 371 mW cm^?2 in wet methane, at 600 °C. The cell also shows exceptional durability against Ni oxidation when tested in wet methane under 0.2 A cm^?2 for 100 h. The improved performance and durability of the catalyst layer has been attributed to the nanosized precipitated Ni and Mn particles distributed on the surface of individual CNMnO particles.     

In-situ exsolved FeRu alloy nanoparticles on Ruddlesden-Popper oxides for direct hydrocarbon fuel solid oxide fuel cells

FeRu alloy (FRA) nanoparticles surface decorated Ruddlesden-Popper type layer perovskite PrSrFe_1-xRu_xO_4+δ (RP-PSFeRu) was prepared by in-situ reduction of the cubic (Pr_0.5Sr_0.5)_0.9Fe_0.9Ru_0.1O_3-δ (P–PSFeRu) in H₂ at 800 °C. When used as the SOFC anode material, it has excellent catalytic activity for H₂ and hydrocarbon fuels. The La_0.8Sr_0.2Ga_0.83Mg_0.17O_3-δ electrolyte supported SOFC single cell with RP-PSFeRu-FRA-GDC composite anode can deliver a maximum power density of 0.75 and 0.50 W cm⁻² in wet H₂ and C₃H₈ at 800 °C, respectively. Furthermore, the single cell shows a stability outputs at a constant current load of 0.5 A cm⁻² in wet H₂ and 0.15 A cm⁻² in wet C₃H₈ fuels, indicating an exceptional stability and cooking resistance.     

Effect of Pd-impregnation on performance,sulfur poisoning and tolerance of Ni/GDC anode of solid oxide fuel cells

Sulfur tolerance of Ni/Gd₂O₃–CeO₂ (Ni/GDC) anodes promoted by impregnated palladium nanoparticles is investigated using the electrochemical impedance spectroscopy (EIS) and galvanostatic polarization techniques in the H₂–H₂S fuels at 800 °C. The anodes are alternately polarized in pure H₂ and H₂S-containing H₂ fuels with H₂S concentration gradually increased from 5 to 700 ppm at 200 mA cm⁻². The degradation in performance for the hydrogen oxidation in H₂S-containing H₂ fuels especially at low H₂S concentration is substantially smaller on Pd-impregnated Ni/GDC cermet anodes, as compared to that on pure Ni/GDC anodes. The potential of Pd-impregnated Ni/GDC electrodes measured in pure H₂ decreases by 0.07 V after exposure to H₂S-containing H₂ fuels, substantially smaller than 0.13 V observed on pure Ni/GDC anodes under identical test conditions. The results show that Pd impregnation significantly enhances the sulfur tolerance of Ni/GDC cermet anodes particularly in the low H₂S concentration range (e.g., <100 ppm). The results indicate that the enhanced sulfur tolerance of Pd impregnated Ni/GDC anodes is most likely due to the promotion effect of impregnated Pd nanoparticles on the hydrogen dissociation and diffusion processes. The reduced moderation of the morphology and microstructure of the anodes in the presence of Pd nanoparticles may be the result of weaker interaction or adsorption of sulfur on Ni and GDC phases.     

ALD CeO2-Coated Pt anode for thin-film solid oxide fuel cells

Surface modification of electrodes for realizing high electrochemical reactivity and thermal stability is an attractive strategy for high-performance low temperature solid oxide fuel cells (LT-SOFCs). Herein, the atomic-layer-deposited (ALD) CeO₂-coated Pt anode structure is fabricated and applied to anodized aluminum oxide (AAO)-based thin-film LT-SOFC. The effect of Pt anode morphology on the infiltration of ALD CeO₂ is elucidated. Anode kinetics are improved in the ALD CeO₂-coated porous Pt anode cell possibly due to the larger Pt–CeO₂ interface density, leading to a decrease in activation resistance by 86%. The maximum power density of the cell with the ALD CeO₂-coated porous Pt anode shows 478 mW/cm²; a dramatic improvement by a factor of two compared to the bare porous Pt anode.