Monoxide Poisoning Research Articles

A plasma partial oxidation approach for removal of leaked LPG in confined spaces

Effective removal of leaked Liquefied petroleum gas (LPG) in poorly ventilated confined spaces remains a huge challenge in emergency response. In this paper, a plasma partial oxidation (PPO) approach was proposed to remove the leaked hazardous gases in confined spaces. A double dielectric barrier discharge (DDBD) reactor with a discharge volume of 13.56 ml was used at an initial Butane (simulate LPG) concentration of 5 % to study the effects of discharge power, gas flow rate and its co-action on the reaction performance, and the feasibility of the removal approach was demonstrated. The main hazardous gases in the exhaust are Butane and CO. By establishing the functional relationship of Butane concentration and CO concentration to energy density, it was calculated that the 5 % initial Butane concentration can be reduced to less than 1.9 % when the energy density (discharge power/gas flow rate) reaches 2.17 kJ/L, which eliminates the explosion risk of leaking Butane, and at the same time, the CO concentration is 0.8 %, which has a low CO toxicity. This paper provides a new approach for removing leaked LPG, which is expected to be practically applied in the disposal of hazardous gas leakage accidents in confined spaces.

Pathological alterations and COHb evaluations as tools for investigating fire-related deaths in veterinary forensic pathology.

Fire-related deaths are usually a consequence of carbon monoxide (CO) poisoning or shock from thermal injuries. In humans, high levels of carboxyhemoglobin (COHb) concentrations in the blood can support a diagnosis of CO poisoning. In veterinary medicine, few studies investigated the pathological changes and blood COHb% in fire victims, and no data are available on post-mortem changes in blood gas composition due to fire. This study aims to investigate the pathological changes and COHb levels in both animal victims of fire and cadavers experimentally exposed to fire. For this purpose, dogs were selected and subdivided into three groups. Group A comprised 9 adult dogs, and Group B comprised 7 puppies that died under fire-related conditions. Group C was represented by 4 dog cadavers experimentally exposed to heat and smoke. A complete macroscopic, histological, and COHb evaluation were performed on each animal. Animals in Groups A and B showed cherry-red discoloration, thermal-injuries and soot deposits along the respiratory tract. Animals in Group C showed thermal injuries and soot deposits limited to the upper respiratory tract. The mean COHb% values in cadavers in Group C were lower than those observed in the other groups but higher compared to the values detected before the heat and smoke treatment. These findings suggest that both pathological changes and COHb analysis are valid tools for investigating fire-related deaths in dogs. However, the increase of COHb levels in cadavers exposed post-mortem to heat and smoke highlights how the COHb analysis should always be evaluated together with macroscopical and microscopical findings to avoid significant misjudgments in investigating fire-related fatalities in veterinary forensic practice.

A DFT-D investigation of the energetic and structural aspects of dehydrogenation of methanol on a bimetallic surface PtGe(110) exploring the germanium effect on the anti-poisoning of pt(110) catalytic activity

Platinum is the most active pure metal for dehydrogenating methanol to create hydrogen, which is crucial for fuel cells. However, one significant disadvantage that reduces the effectiveness and long-term performance of platinum catalysts is their susceptibility to CO poisoning. In the current study, we examine and elucidate the promotional impact of Ge on Pt catalysts with increased resistance to deactivation by CO poisoning. We do this by combining partial density of states calculations with electronic configuration and Mulliken atomic charges. The self-consistent periodic density functional theory with dispersion correction (DFT-D) was used to investigate the methanol adsorption and dehydrogenation mechanisms on the surface of PtGe (110). On the surface, several adsorption mechanisms of pertinent intermediates were found. Furthermore, a thorough analysis of a reaction network comprising four reaction paths revealed that, in terms of activation barriers, the first O—H bond scission of CH3OH appears to be more advantageous than C—H bond cleavage on the PtGe(110) surface. Additionally, it has been demonstrated that the main route on the PtGe(110) surface is CH3OH→CH3O→CH2O→CHO→CO evolution. The remarkable differences in the predominant reaction pathway on the Pt(110) surface, and PtGe(110) surface indicate that the Ge-doped Pt Nano catalyst is more selective and resistant to deactivation.

Multi-scale revealing how real catalyst layer interfaces dominate the local oxygen transport resistance in ultra-low platinum PEMFC

In view of a catalyst layer (CL) with low-Pt causing higher local transport resistance of O2 (Rlocal), we propose a multi-study methodology that combines CO poisoning, the limiting current density method, and electrochemical impedance spectroscopy to reveal how real CL interfaces dominate Rlocal. Experimental results indicate that the ionomer is not evenly distributed on the catalyst surface, and the uniformity of ionomer distribution does not show a positive correlation with the ionomer content. When the ionomer coverage on the supported catalyst surface is below 20 %, the ECSA is only 10 m2·g−1, and the ionomer coverage on the supported catalyst surface reaches 60 %, the ECSA is close to 40 m2·g−1. The ECSA has a positive correlation with ionomer coverage. Because the ECSA is measured by CO poisoning, it can be inferred that the platinum contacted with ionomer can generate effective active sites. Furthermore, a more uniform distribution of ionomer can create additional proton transport channels and reduce the distance for oxygen transport from the catalyst layer bulk to the active sites. A higher ECSA and a shorter distance for oxygen transport will reduce the Rlocal, leading to better performance.

Carbon monoxide poisoning with hippocampi lesions on MRI: cases report and literature review

BackgroundCarbon monoxide (CO) poisoning is now one of the leading causes of poisoning-related mortality worldwide. The central nervous system is the most vulnerable structure in acute CO poisoning. MRI is of great significance in the diagnosis and prognosis of CO toxic encephalopathy. The imaging features of CO poisoning are diverse. We report atypical hippocampal lesions observed on MRI in four patients after acute CO exposure.Case presentationsWe report four patients who presented to the emergency department with loss of consciousness. The diagnosis of CO poisoning was confirmed on the basis of their detailed history, physical examination and laboratory tests. Brain MRI in all of these patients revealed abnormal signal intensity in hippocampi bilaterally. They all received hyperbaric oxygen therapy. The prognosis of all four patients was poor.ConclusionHippocampi, as a relatively rare lesion on MRI of CO poisoning, is of important significance both in the early and delayed stages of acute CO poisoning. In this article, we summarize the case reports of hippocampal lesions on MRI in patients with CO poisoning in recent years, in order to provide reference for the diagnosis and prognosis of CO poisoning.

A highly oxygen reduction reaction active and CO2 durable high-entropy cathode for solid oxide fuel cells

One big obstacle for the oxygen reduction reaction (ORR) electrode in solid oxide fuel cells (SOFCs) is the poor reaction activity and fast degradations caused by CO2 poisoning. Here we report our design of an active A-site Ca-rich high-entropy Pr0.1875Ba0.1875Sr0.1875La0.1875Ca0.25CoO3-δ (PBSLC25C) electrode, guided by the O p-band theory. When applied as a cathode in solid oxide fuel cells (SOFCs), it demonstrates high ORR activity and excellent CO2 tolerance under realistic operating conditions. Ni-YSZ-based anode-supported cells with PBSLC25C cathodes demonstrate excellent peak power densities of 1.14 W cm−2, 1.04 W cm−2, and 0.77 W cm−2 in the air with 1%, 5%, and 10% CO2, respectively, at 750 °C. The engineered high-entropy PBSLC25C effectively diminishes the CO2 poisoning effect and maintains active surfaces for fast oxygen exchange, as confirmed by the cell durability test in air containing CO2 (5 and 10 vol%), Raman spectroscopy, and density functional theory calculations.

Overcoming poisoning issues in hydrogen fuel cells with face-centered tetragonal FePt bimetallic catalysts

Hydrogen fuel cells are expected to play a central role in the next-generation energy paradigm. However, owing to practical limitations, hydrogen is supplied in the form of refined hydrocarbons or alcohols in industrial applications. Among them, methanol is widely used as a hydrogen source, and CO is inevitably generated during its oxidation process. Even a small amount of CO (∼20 ppm) strongly binds to Pt used as a catalyst, and deactivates it. In addition to CO, surface adsorption of organic cations by binder or ionomer use in alkaline fuel cells is also one of the poisoning issues to be overcome. Herein, we propose FePt bimetallic catalysts that can resist unavoidable CO and organic cation poisoning. Our synthetic strategy, including annealing and acid treatment, allows the catalysts to possess different alloying degrees and surface structures, which in turn induce different levels of resistance to CO and organic-cation poisonings. The correlation between the surface and bulk structures of the catalysts and poisoning resistance was elucidated through X-ray photoemission spectroscopy and electrochemical analysis. The results revealed that an FePt catalyst having an ordered atomic arrangement displayed a better poisoning resistance than that having a disordered arrangement.

Enhanced CO adsorption and *CO hydrogenation for efficient CO2 deep reduction on MnCu-NC

In CO2RR, enhancing CO adsorption could suppress desorption and increase *CO concentration for deep reduction. An underlying concern is that strong adsorption might result in high thermodynamic barrier for *CO hydrogenation, however, kinetic barrier firstly dominates the reaction pathway and determines the products selectivity. Directed by above idea, CO2RR performance on Mn, Cu doped nitrogenated carbon (MnCu-NC) is comprehensively studied using density functional theory (DFT). MnCu-NC shows a mild limiting potential of −0.59 V (*CO → *CHO) for CH3OH and CH4 products. CO poisoning is likely to cause catalyst deactivation, while CO modified MnCu-NC shows a slightly increased limiting potential of −0.63 V (*COCO → *COCHO) for CH3OH and CH4, and hydrogen evolution is significantly suppressed. Further comparative studies indicate that kinetic barrier for *CO hydrogenation is crucial for deep reduction, and C–O activation, as well as CO adsorption is enhanced by Π-backbonding. Besides, introduction Cu to dual-atom catalyst (DAC) could help retain more electrons and Mn has strong magnetization for charge transfer, both of which improve the charge densities and Π-backbonding strength, thus boosting the remarkable CO2RR performance toward CH4 and CH3OH on MnCu-NC.

ZnMo-MOF as anti-CO hydrogen electrocatalyst enhance microbial electrosynthesis for CO/CO2 conversion

Microbial electrosynthesis (MES) is an electrically driven technology that can be used for converting CO/CO2 into chemicals. The unique electronic and substrate properties of CO make it an important research target for MES. However, CO can poison the cathode and increase the overpotential of hydrogen evolution reaction (HER), thus reducing the electron transfer rate via H2. This work evaluated the effect of an anti-CO HER catalyst on the performance of MES for CO/CO2 conversion. ZnMo-metal–organic framework (MOF) materials with different calcination temperatures were synthesized. ZnMo-MOF-800 with Mo2C nanoparticles as active centers exhibited excellent resistance to CO toxicity. It also obtained the highest hydrogen evolution and enhanced electron transfer rate in CO atmosphere. MES with ZnMo-MOF-800 cathode and Clostridium ljungdahlii as biocatalyst obtained 0.31 g L−1 d−1 acetate yield, 0.1 g L−1 d−1 butyrate yield, and 0.09 g L−1 d−1 2,3-butanediol yield in CO/CO2, while Pt/C only get 0.076 g L−1 d−1 acetate yield, 0.05 g L−1 d−1 butyrate yield and 0.02 g L−1 d−1 2,3-butanediol yield. ZnMo-MOF-800 was conducive to biofilm formation, enabling it to better resist CO toxicity. This work provides new opportunities for constructing a highly efficient cathode with an anti-CO hydrogen evolution catalyst to enhance CO/CO2 conversion in MES.

Chrysanthemum‐Flowers‐Like Bimetal Oxide Based Electrocatalyst for Methanol Oxidation Reaction

Transition metal oxides have garnered attention for the methanol electro‐oxidation reaction owing to their easy availability, high catalytic applicability, and multiple oxidation capabilities. Bimetal‐based catalysts further enhance the performance of the methanol oxidation reaction. In this context, a chrysanthemum‐flower‐like MoO2/WO3 is synthesized through a solvothermal and annealing strategy. The morphology attests to the rough surface and pores in the catalyst, augmenting its surface area for reactions and enhancing catalytic applicability. Electrochemical oxidation of methanol yields an optimal current density of 0.99 mA cm−2 and 2.07 mA mg−1 at a potential of 0.57 V versus Ag/AgCl. The catalyst exhibits a remarkably low Tafel slope of 37.45 mV dec−1, affirming its rapid reaction kinetics. Electrochemical impedance spectroscopy (EIS) reveals an equivalent electronic circuit of R(Q(R(QR)Q(RW))), confirming low charge transfer resistance (Rct) and diffusion‐controlled kinetics attributable to the pores in the sample. The sample also demonstrates an electrochemically active surface area (ECSA) value equal to 0.122 mF cm−2 and long‐term stability over continuous 5000 s, exhibiting no change and high resistance to CO poisoning. All these characterizations and obtained results collectively affirm that the chrysanthemum‐flower‐like MoO2/WO3 serves as a highly suitable electrocatalyst for the electrochemical oxidation of methanol.

Postmortem concentrations for total blood carbon monoxide (TBCO) as novel biomarker for carbon monoxide (CO) poisonings.

Total Blood Carbon Monoxide (TBCO) showed promising results in improving accuracy of CO determinations in blood and presenting better stability to different storage conditions. Therefore, it was proposed as alternative biomarker to carboxyhemoglobin (COHb) for CO poisoning diagnosis. However, given that current interpretation reference values exist for COHb only, it is difficult to implement TBCO analysis in routine. Therefore, we aimed at determining TBCO reference values for postmortem CO poisoning cases. A previously validated method for TBCO analysis via gas chromatography-mass spectrometry was applied to cardiac, peripheral, cranial and spleen blood samples collected from 92 autopsies. Autopsy cases included 21 non-CO related and 71 CO-related cases with varying postmortem intervals (PMI). Statistical analyses were performed using statistical software R Studio. When comparing lower to higher PMI for non-CO related cases, no significant differences were found, which suggests that CO formation or degradation at low PMIs does not occur. Spleen blood showed potential as alternative matrix for CO determinations in cases with sample availability issues, but needs to be evaluated for CO positive cases. Results for cardiac blood in CO-related autopsies showed a positive correlation between COHb and TBCO values (R = 0.78). This value is lower than what is found in the literature, suggesting that even though COHb and TBCO are correlated, a potential underestimation of the true CO exposure might occur if only COHb values are taken into consideration. Samples were divided into CO exposure groups based on COHb concentrations and with the data obtained, classification into following TBCO concentration groups are proposed: no significant CO exposure case <6 µmol/mL, medium CO exposure case 6-20 µmol/mL, high CO exposure case >20µmol/mL. Even if a higher number of samples in each group would enable to increase the confidence, these results are very promising and highlight the importance of TBCO measurement.

Carbon Monoxide Poisoning: From Occupational Health to Emergency Medicine.

Carbon monoxide poisoning remains a leading cause of accidental poisoning worldwide (both at home and at work), and it is also a cause of suicidal poisoning. Such poisoning can arise following prolonged exposure to low levels of CO or following brief exposure to high concentrations of the gas. In fact, despite exposure limits, high safety standards, and the availability of CO alarms, nearly 50,000 people in the United States visit the emergency department each year due to poisoning. Additionally, CO poisoning in the United States causes up to 500 deaths each year. Despite the widespread nature of this form of poisoning, known about for centuries and whose damage mechanisms have been recognized (or rather hypothesized about) since the 1800s, early recognition, especially of late complications, and treatment remain a medical challenge. A well-designed therapeutic diagnostic process is necessary so that indication for hyperbaric or normobaric therapy is correctly made and so that patients are followed up even after acute exposure to diagnose late complications early. Furthermore, it is necessary to consider that in the setting of emergency medicine, CO poisoning can be part of a differential diagnosis along with other more frequent conditions, making its recognition difficult. The last thirty years have been marked by a significant increase in knowledge regarding the toxicity of CO, as well as its functioning and its importance at physiological concentrations in mammalian systems. This review, taking into account the significant progress made in recent years, aims to reconsider the pathogenicity of CO, which is not trivially just poisonous to tissues. A revision of the paradigm, especially as regards treatment and sequelae, appears necessary, and new studies should focus on this new point of view.

Single is not combined: The role of Co and Ni bioavailability on toxicity mechanisms in liver and brain cells

The two trace elements cobalt (Co) and nickel (Ni) are widely distributed in the environment due to the increasing industrial application, for example in lithium-ion batteries. Both metals are known to cause detrimental health impacts to humans when overexposed and both are supposed to be a risk factor for various diseases. The individual toxicity of Co and Ni has been partially investigated, however the underlying mechanisms, as well as the interactions of both remain unknown.In this study, we focused on the treatment of liver carcinoma (HepG2) and astrocytoma (CCF-STTG1) cells as a model for the target sites of these two metals. We investigated their effects in single and combined exposure on cell survival, cell death mechanisms, bioavailability, and the induction of oxidative stress. The combination of CoCl2 and NiCl2 resulted in higher Co levels with subsequent decreased amount of Ni compared to the individual treatment. Only CoCl2 and the combination of both metals led to RONS induction and increased GSSG formation, while apoptosis and necrosis seem to be involved in the cell death mechanisms of both CoCl2 and NiCl2. Collectively, this study demonstrates cell-type specific toxicity, with HepG2 representing the more sensitive cell line. Importantly, combined exposure to CoCl2 and NiCl2 is more toxic than single exposure, which may originate partly from the respective cellular Co and Ni content. Our data imply that the major mechanism of joint toxicity is associated with oxidative stress. More studies are needed to assess toxicity after combined exposure to elements such as Co and Ni to advance an improved hazard prediction for less artificial and more real-life exposure scenarios.

DFT insights into doping and oxygen vacancy effects on CO and CO₂ adsorptions over CuAl2O4 spinel surfaces

Introducing transition metals into CuAl2O4 spinel enhances catalyst stability and Cu sintering resistance in methanol steam reforming. Yet, the influence of doping on vacancy formation and the adsorption behaviors of CO2 (the primary product) and CO (the notorious byproduct) remains unclear. Herein, we employed DFT + U to investigate CO and CO2 adsorption on perfect, M-doped (Fe, Co, and Ni), and M-doped oxygen-deficient CuAl2O4 spinel (100) and (110) surfaces. We find that stronger CO adsorption on (100) than (110) surfaces across all M-doped surfaces, while CO2 adsorbs more stronger on (110) surfaces. The weakened CO adsorptions are observed on Fe and Ni-doped surfaces, demonstrating that doping plays a significant role in improving the resistance to CO poisoning. Co-doping promotes CO adsorption via a CO3-like structure on CuAl2O4(110) surface and boosts the CO oxidation. Furthermore, infrared spectroscopy simulation indicates that the vibrational frequencies for CO linear adsorption, formation of bent CO2- and CO3-like structures are within the ranges of 2042–2078, 1463–1566, and 1497–1816 cm−1, respectively. In addition, Ov on Ni-doped surfaces can significantly strengthen the CO2 adsorption by 0.6–1.3 eV, highlighting the doping and oxygen-defect engineering in enhancing the CO2 capture. This research uncovers the critical impact of metal doping and oxygen vacancies on CO and CO2 adsorptions over CuAl2O4 spinel catalyst, providing insights for developing catalysts with improved resistance to CO poisoning and enhanced CO oxidation which is vital for methanol steam reforming.

Advanced Ru/Ti4O7 catalyst for Tolerating CO and H2S poisoning to hydrogen oxidation reaction

CO and H2S poisoning of Pt-based catalysts for hydrogen oxidation reaction (HOR) stands as one of the long-standing hindrances to the widespread commercialization of proton exchange membrane fuel cells. In this paper, a Ru/Ti4O7 catalyst is successfully synthesized by the microwave-thermal method. This Ru/Ti4O7 catalyst shows a much higher noble metal mass activity than those of commercial PtRu/C and conventional Ru/C catalysts. The performance of the Ru/Ti4O7 catalyst under the exist of CO or H2S shows insignificant current decay, which is far superior to commercial PtRu/C and Pt/C catalysts. In this Ru/Ti4O7 catalyst, the electron transfer between Ru and Ti to form d-p orbital hybridization is considered to be responsible for the favorable catalytic HOR performance and the corresponding CO and H2S tolerance. The interaction mechanism formed by electron transfer may open a promising way for the subsequent development of anti-poisoning catalysts for PEM fuel cell hydrogen oxidation reaction.

N-doped hollow carbon nanospheres embedded in N-doped graphene loaded with palladium nanoparticles as an efficient electrocatalyst for formic acid oxidation

Efficient electrocatalysts with a low cost, high activity and good durability play a crucial role in the use of direct formic acid fuel cells. Pd nanoparticles supported on N-doped hollow carbon nanospheres (NHCNs) embedded in an assembly of N-doped graphene (NG) with a three-dimensional (3D) porous structure by a simple and economical method were investigated as direct formic acid fuel cell catalysts. Because of the unique porous configuration of interconnected layers doped with nitrogen atoms, the Pd/NHCN@NG catalyst with Pd nanoparticles has a large catalytic active surface area, superior electrocatalytic activity, a high steady-state current density, and a strong resistance to CO poisoning, far surpassing those of conventional Pd/C, Pd/NG, and Pd/NHCN catalysts for formic acid electrooxidation. When the HCN/GO mass ratio was 1:1, the Pd/NHCN@NG catalyst had an outstanding performance in the catalytic oxidation of formic acid, with an activity 4.21 times that of Pd/C. This work indicates a way to produce superior carbon-based support materials for electrocatalysts, which will be beneficial for the development of fuel cells.

Electrocatalysis Boosts the Methanol Thermocatalytic Dehydrogenation for High-Purity H2 and CO Production.

Hydrogen production from methanol represents an energy-sustainable way to produce ethanol, but it normally results in heavy CO2 emissions. The selective conversion of methanol into H2 and valuable chemical feedstocks offers a promising strategy; however, it is limited by the harsh operating conditions and low conversion efficiency. Herein, we realize efficient high-purity H2 and CO production from methanol by coupling the thermocatalytic methanol dehydrogenation with electrocatalytic hydrogen oxidation on a bifunctional Ru/C catalyst. Electrocatalysis enables the acceleration of C-H cleavage and reduces the partial pressure of hydrogen at the anode, which drives the chemical equilibrium and significantly enhances methanol dehydrogenation. Furthermore, a bilayer Ru/C + Pd/C electrode is designed to mitigate CO poisoning and facilitate hydrogen oxidation. As a result, a high yield of H2 (558.54 mmol h-1 g-1) with high purity (99.9%) was achieved by integrating an applied cell voltage of 0.4 V at 200 °C, superior to the conventional thermal and electrocatalytic processes, and CO is the main product at the anode. This work presents a new avenue for efficient H2 production together with valuable chemical synthesis from methanol.

IDENTIFICATION OF K3 HAZARD RISK IN FIREFIGHTERS AT MEDAN CITY FIRE AND RESCUE SERVICE

Firefighters are particularly vulnerable to several work-related illnesses and injuries, including toxic gas poisoning, burns, respiratory distress, and bodily injury. Therefore, an important first step in implementing successful prevention tactics is to identify possible K3 hazards precisely and accurately. To prevent industrial accidents that endanger workers due to hazards arising in the Medan City Fire and Rescue Department, the purpose of this study is to identify hazards and evaluate risks using the HIRA method analysis. The research was conducted using qualitative methodology. Three data collection methods were used: documentation, in-depth interviews, and observation. The informants in this study amounted to 4 people consisting of 2 key informants and 2 main informants. Based on the results of hazard identification and risk assessment, there are 19 accident risks spread across 5 activities in the Medan City Fire and Rescue Service. Based on the results of the study, it was concluded that 10 potential hazards fall into the meaningful category, 4 potential hazards fall into the medium-risk category, 4 potential hazards fall into the low-risk category, and high-risk categories as many as 1 potential hazard. Based on these conclusions, suggestions were submitted to the Medan City Fire and Rescue Service to increase the provision of personal protective equipment (PPE) such as gloves, helmets, heat-resistant shirts, and pants, and SCBA was an anticipation of the proposal submitted to the Medan City Fire and Rescue Service. Medan City Fire and Rescue Officers are also required to always comply with established work rules to reduce risks and avoid work accidents.

The influence of phosphorus and CO poisoning on Pd/SSZ-13 with different Al distributions as passive NOx adsorbers

Phosphorus and CO are typical poisonous substances under realistic working conditions for Pd/SSZ-13 passive NOx Adsorbers (PNA). In this research, the Pd/SSZ-13 with different Al distributions were subject to phosphorus and CO poisoning. The characterization results indicated the resistance to both P and CO increased with the amount of paired Al on SSZ-13 support. Paired Al facilitated the formation of Pd2+Z2 which was more stable against [Pd(OH)]+ under P poisoning. The Pd2+ preferred to transform to Pd+ after poisoning while the [Pd(OH)]+ was more likely turned to agglomerated Pd. The Al-Pd-Al structure also mitigated dealumination during P poisoning. On the other hand, paired Al promoted the ion-exchange of Pd on the SSZ-13 support and led to a more homogeneous Pd distribution. This effectively alleviated the Ostwald ripening and particle migration thus preserving the performance of the catalyst under CO atmosphere. This study provided a new perspective for designing PNA materials with high resistance.

Designing highly active and CO2 tolerant heterostructure electrode materials by a facile A-site deficiency strategy in Pr1-xBaCo2O5+δ double perovskite

Solid oxide fuel cells (SOFCs) have received continuous attention as an energy conversion device, and the development of highly electrochemically active materials is important. In this work, highly active and CO2 tolerant BaBixCo1-xO3@PrBaCo2O5+δ heterostructure electrode materials were fabricated by a facile A-site deficiency in Pr1-xBaCo2O5+δ double perovskite. A-site excess-deficient Pr0.8BaCo2O5+δ (PBC80) double-perovskite oxide were prepared and designed to induce the self-assembly dissolution to form BaCoO3-δ (BCO) heterostructure through cationic high-concentration deficiency. However, the surface-dissolved alkaline earth metal (Ba2+) readily forms carbonates with CO2, which severely limits the cathode catalytic activity and long-term stability. Thus, bismuth ion-modified PBC80 (BBCO@PBCO) was prepared to further tailor the material properties, which provides more active sites for oxygen reduction reaction (ORR) by strengthening the synergistic interaction between the heterogeneous interfaces. More importantly, BBCO@PBCO exhibits the most stable Area specific resistance (ASR) under CO2 atmosphere, indicating the incorporation of acidic Bi ions effectively mitigated the adsorption and reaction between the material and the acidic gas CO2. These results indicate that the heterostructure induced by A-site deficiency promotes the ORR activity of PrBaCo2O5+δ cathode, while further modification of Bi ions enhances both the electrochemical activity and the stability of the materials, delivering superior resistance to CO2 poisoning.