Pulsed electrolysis of carbon dioxide by large‐scale solid oxide electrolytic cells for intermittent renewable energy storage

Abstract

CO2 electrolysis with solid oxide electrolytic cells (SOECs) using intermittently available renewable energy has potential applications for carbon neutrality and energy storage. In this study, a pulsed current strategy is used to replicate intermittent energy availability, and the stability and conversion rate of the cyclic operation by a large‐scale flat‐tube SOEC are studied. One hundred cycles under pulsed current ranging from −100 to −300 mA/cm2 with a total operating time of about 800 h were carried out. The results show that after 100 cycles, the cell voltage attenuates by 0.041%/cycle in the high current stage of −300 mA/cm2, indicating that the lifetime of the cell can reach up to about 500 cycles. The total CO2 conversion rate reached 52%, which is close to the theoretical value of 54.3% at −300 mA/cm2, and the calculated efficiency approached 98.2%, assuming heat recycling. This study illustrates the significant advantages of SOEC in efficient electrochemical energy conversion, carbon emission mitigation, and seasonal energy storage.

Comprehensive understanding and rational regulation of microenvironment for gas‐involving electrochemical reactions

“…Hong et al 80 constructed in situ nanoalloying Pd–Ni as a catalyst in the fuel–electrode substrate of solid‐oxide cells, obtaining a CO 2 conversion rate of 57.7% and a CO selectivity of 28.8% (Figure 4B,C). Singhal et al 85 used a pulsed current strategy to enhance CO 2 RR in a flat‐tube solid‐oxide cell, exhibiting a 52% CO 2 conversion rate, which is close to the theoretical value of 54.3% at −300 mA cm −2 . In addition, the energy conversion efficiency can reach 98.2% when heat recycling is included.…”

Effect of the steam/hydrogen ratio on the performance of flat-tube solid oxide electrolysis cells for seawater

“…To quantify the Ni agglomeration, migration, and particle loss in the fuel electrode, the area of Ni particles was calculated using Image J software. 33–35 Fig. 6g reveals the relationship between the distributions of Ni content at different distances from the YSZ electrolyte.…”

“…To quantify the Ni agglomeration, migration, and particle loss in the fuel electrode, the area of Ni particles was calculated using Image J soware. [33][34][35] As shown in Fig. 6h, the percentages of small Ni particles between 0 and 0.6 mm 2 in cell 1 and cell 2 are 54.94 and 62.16%, respectively, which are lower than that of 69.63% in the reference cell; while the percentages of larger Ni particles between 0.6 and 1.2 mm 2 are 29.01 and 21.08%, higher than that of 17.84% in the reference cell.…”

Visiting the roles of Sr‐ or Ca‐ doping on the oxygen reduction reaction activity and stability of a perovskite cathode for proton conducting solid oxide fuel cells

“…As a result, many cathode materials that work well at high temperatures in oxygen ion‐conducting SOFCS may perform limited activity or durability on H‐SOFCs 12,14 . Through extensive research, mixed ionic electronic conductors with enlarged electrochemical reaction regions have been successfully developed and achieved higher electrochemical activity 15‐19 . With higher chemical diffusion and surface exchange coefficients, layered LnBaCo 2 O 5+δ ‐based perovskites exhibit better electrochemical performance, compared to ABO 3 ‐type perovskites 20,21 .…”

“…12,14 Through extensive research, mixed ionic electronic conductors with enlarged electrochemical reaction regions have been successfully developed and achieved higher electrochemical activity. [15][16][17][18][19] With higher chemical diffusion and surface exchange coefficients, layered LnBaCo 2 O 5+δ -based perovskites exhibit better electrochemical performance, compared to ABO 3 -type perovskites. 20,21 Among them, PrBaCo 2 O 6 (PBC) system materials appear to have the best electrochemical properties and are widely investigated.…”