H2 CO2 Research Articles

The photocatalytic hydrogen evolution and photoreduction CO2 selective enhancement of Co3O4/Ti3+-TiO2/NiO hollow core-shell dual pn junction

The potential and threshold would be the most important issues for photocatalysis, including hydrogen evolution reaction (HER) and CO2 selective photoreduction. The Co3O4/Ti3+-TiO2/NiO hollow core-shell heterojunction is fabricated via a continuous chemical-hydrothermal-annealing-reduction method. As demonstrated, the as-prepared Co3O4/Ti3+-TiO2/NiO hollow core-shell heterojunction exhibits remarkable photocatalytic performance enhancement than single TiO2, including H2 evolution (∼2134.63 μmol/g∙h, ∼80 folds) and CO2 photoreduction (H2/CH4/CO: ∼34.85/132.25/12.65 μmol/g∙h, ∼30 folds), and achieves enhanced CO2 photoreduction selectivity, which can be mainly ascribed to the synergism of Ti3+/Ov and dual pn junction. There, the Ti3+/Ov can not only increase the solar efficiency, but also decrease the threshold of H2O*→H* and *CO→*CHO to enhance HER and CH4 selectivity, including promote H+ diffusion and H2O/CO2/*CO absorption. All these can be supported by the density functional theory (DFT) calculation. Additionally, the formed Co3O4/Ti3+-TiO2/NiO dual pn junction can promote the photo-generated carrier separation/transport efficiently. Furthermore, the hollow core-shell structure obtained by Cobalt 2-methylimidazole (ZIF-67) self-template can increase solar efficiency, and the NiO nanosheets and Co3O4 nanoparticles can increase active sites.

Synergy of yolk-shelled structure and tunable oxygen defect over CdS/CdCO3-CoS2: Wide band-gap semiconductors assist in efficient visible-light-driven H2 production and CO2 reduction

Yolk-shelled CoS2 nanospheres are designed through Kirkendall Effect and subsequently converted into defect-rich CdS/CdCO3-CoS2 photocatalysts via in-situ growth method. The optimal CdS/CdCO3-CoS2 exhibits a significant hydrogen evolution rate of 64867.88 μmol h−1 gcat−1 that is 3.23 and 49.45 folds higher than CoS2-CdS and pure CdS. CO2 reduction rate of CdS/CdCO3-CoS2 is detected additionally (654.7 μmol h−1 gcat−1). Yolk-shelled CdS/CdCO3-CoS2 induces the multi-scattering of incident light, possessing 1.52-fold H2 production rate than that of full hollow ones. Enhanced photoexcited-carriers migration efficiency is attributed to the synergistic effect between possible Mie resonance at about λ = 450 nm in yolk-shelled architecture based on Mie’s theory and monochromatic light HER test, and the formation of defect energy level within the wide-band gap of CdCO3 in Schottky-type/type II heterojunction. Electron paramagnetic resonance, positron annihilation spectroscopy and density functional theory calculation etc. are employed to validate the presence of oxygen vacancies and the photocatalytic mechanism.

Ca12Al14O33 or MgO supported Ni-carbide slag bi-functional materials for H2 production and CO2 capture in sorption-enhanced steam gasification of cellulose/polyethylene mixture

Co-gasification of biomass and waste plastics is a promising technology for H2 production. In this work, Ni-CaO-Ca12Al14O33 and Ni-CaO-MgO bi-functional materials were prepared from carbide slag for H2 production in sorption-enhanced steam gasification experiments of cellulose/polyethylene mixtures. The H2 production and CO2 capture performances of Ni-CaO-Ca12Al14O33 and Ni-CaO-MgO in sorption-enhanced steam gasification of cellulose/polyethylene were studied and compared. Density functional theory calculations, including the density of states, electron differential densities, and adsorption energies were performed to investigate the effect of supports on the stability and reactivity of Ni-CaO-based bifunctional materials at a microscopic level. The results exhibit that polyethene contributes to improving the H2 production effectiveness of cellulose sorption-enhanced steam gasification, the optimum mass ratio of cellulose to polyethene is 0.5:0.5. The CO2 capture capacity, H2 yield, and H2 concentration using Ni-CaO-Ca12Al14O33 can be respectively 2.0, 2.6, and 1.4 times as high as those using Ni-CaO-MgO in the 20th cycle, which indicates the higher cyclic stability and catalytic activity of Ni-CaO-Ca12Al14O33. Density functional theory results also indicate that Ca12Al14O33 can better retain the stable structure of Ni-CaO-based materials, which is consistent with the experimental results. Compared with MgO, Ca12Al14O33 is a better framework for Ni-CaO-based bifunctional material for H2 production in the sorption-enhanced steam gasification process.

Design of efficient noble metal single-atom and cluster catalysts toward low-temperature preferential oxidation of CO in H2

The preferential oxidation of CO in H2 is attractive for the removal of trace amounts of CO to meet the requirement of proton-exchange membrane fuel cells (PEMFCs) application. The key is to design highly effective catalysts that work well in a wide range of low temperatures. Here, the recent progress in Au and Pt group metal catalysts for the PROX reaction is summarized, covering those with single-atom and cluster dispersed metal species with remarkable performance. Firstly, the progress of some representative catalysts is overviewed, with an emphasis on the strategies for improving low-temperature activity, selectivity, and stability. Then, special attention is focused on the key parameters affecting performance in the PROX reaction. Moreover, the reaction mechanisms in terms of adsorption and activation of reactants are discussed. Finally, the challenges and opportunities are offered for guiding the design of advanced noble metal catalysts toward the PROX process.

Water Saturated with Pressurized CO2 as a Tool to Create Various 3D Morphologies of Composites Based on Chitosan and Copper Nanoparticles.

Methods for creating various 3D morphologies of composites based on chitosan and copper nanoparticles stabilized by it in carbonic acid solutions formed under high pressure of saturating CO2 were developed. This work includes a comprehensive analysis of the regularities of copper nanoparticles stabilization and reduction with chitosan, studied by IR and UV-vis spectroscopies, XPS, TEM and rheology. Chitosan can partially reduce Cu2+ ions in aqueous solutions to small-sized, spherical copper nanoparticles with a low degree of polydispersity; the process is accompanied by the formation of an elastic polymer hydrogel. The resulting composites demonstrate antimicrobial activity against both fungi and bacteria. Exposing the hydrogels to the mixture of He or H2 gases and CO2 fluid under high pressure makes it possible to increase the porosity of hydrogels significantly, as well as decrease their pore size. Composite capsules show sufficient resistance to various conditions and reusable catalytic activity in the reduction of nitrobenzene to aniline reaction. The relative simplicity of the proposed method and at the same time its profound advantages (such as environmental friendliness, extra purity) indicate an interesting role of this study for various applications of materials based on chitosan and metals.

Recent advances in titanium carbide MXene-based nanotextures with influential effect of synthesis parameters for solar CO2 reduction and H2 production: A critical review

Photocatalytic solar to energy conversion is considered an attractive approach for overcoming energy crises and environmental concerns. Recently, titanium carbide (Ti3C2) MXenes have been recognized as promising cocatalysts based on their metallic conductivity, excessive active reaction sites, and enlarged surface area. The current review focuses on the properties and applications of Ti3C2 MXenes useful in the field of photocatalysis. More specifically, surface modification of Ti3C2 MXenes by varying synthesis parameters to get pure materials and also composites with the role of functional groups towards solar energy conversion applications is highlighted in this review. The effect of etching and oxidizing pathways to get an efficient cocatalyst has been discussed in detail. Considering the significant effect of parameters, optimum synthesis conditions such as etchant type, concentration, time and type of intercalant in both the Ti3C2 synthesis approaches for improved photoactivity are discussed. Additionally, the surface modification of Ti3C2 through oxidation for TiO2 growth on its surface is deliberated with a detailed discussion on etchant type, concentration, etching time, and environmental factors. The optimum oxidation condition, including temperature, time, and environment for thermal treatment of Ti3C2, were also included. Lastly, the review summarizes the conclusion and future perspectives for solar energy conversion applications.

Development of Power-to-X Catalytic Processes for CO2 Valorisation: From the Molecular Level to the Reactor Architecture

Nowadays, global climate change is likely the most compelling problem mankind is facing. In this scenario, decarbonisation of the chemical industry is one of the global challenges that the scientific community needs to address in the immediate future. Catalysis and catalytic processes are called to play a decisive role in the transition to a more sustainable and low-carbon future. This critical review analyses the unique advantages of structured reactors (isothermicity, a wide range of residence times availability, complex geometries) with the multifunctional design of efficient catalysts to synthesise chemicals using CO2 and renewable H2 in a Power-to-X (PTX) strategy. Fine-chemistry synthetic methods and advanced in situ/operando techniques are essential to elucidate the changes of the catalysts during the studied reaction, thus gathering fundamental information about the active species and reaction mechanisms. Such information becomes crucial to refine the catalyst’s formulation and boost the reaction’s performance. On the other hand, reactors architecture allows flow pattern and temperature control, the management of strong thermal effects and the incorporation of specifically designed materials as catalytically active phases are expected to significantly contribute to the advance in the valorisation of CO2 in the form of high added-value products. From a general perspective, this paper aims to update the state of the art in Carbon Capture and Utilisation (CCU) and PTX concepts with emphasis on processes involving the transformation of CO2 into targeted fuels and platform chemicals, combining innovation from the point of view of both structured reactor design and multifunctional catalysts development.

Effect of multi-component gases on the behavior and mechanism of carbon deposition in hydrogen-rich blast furnaces

Hydrogen-rich blast furnace is considered an advanced technology in the iron and steel industry for reducing carbon emissions at the source. The CO utilization is instead reduced due to the severe carbon deposition behavior after hydrogen enrichment. This paper quantitatively investigated the effect of CO–H2–H2O–N2 multi-component on carbon deposition behavior, and a formation mechanism of deposited carbon was proposed finally. The results revealed that the optimum temperature range for carbon deposition was about 470–900 °C, and the maximum rate of carbon deposition was reached at 550–700 °C. At 600 °C, the carbon deposition rate for 100%CO and 40%CO–60%N2 were 0.54 g/d and 0.13 g/d, respectively. The aggravating effect of H2 to carbon deposition was 5.2 times that of H2O. Whereas the carbon deposition will be constrained in low CO and high H2 environment. The SEM showed that the morphology of the deposited carbon was filamentous, its formation mechanism on the iron surface is: (a) Adsorption of gases on the iron surface, (b) Formation of Fe3C layer, (c) Deposition of graphite layer, (d) Decomposition of Fe3C layer, (e) Formation of Fe3C–Fe + C (diss.) catalytic particles, (f) Formation of filamentous carbon, (g) Carbon activity in metallic Fe-filamentous carbon.

Plasmon-Induced Semiconductor-Based Photo-Thermal Catalysis: Fundamentals, Critical Aspects, Design, and Applications

Photo-thermal catalysis is among the most effective alternative pathways used to perform chemical reactions under solar irradiation. The synergistic contributions of heat and light during photo-thermal catalytic processes can effectively improve reaction efficiency and alter design selectivity, even under operational instability. The present review focuses on the recent advances in photo-thermal-driven chemical reactions, basic physics behind the localized surface plasmon resonance (LSPR) formation and enhancement, pathways of charge carrier generation and transfer between plasmonic nanostructures and photo-thermal conversion, critical aspects influencing photo-thermal catalytic performance, tailored symmetry, and morphology engineering used to design efficient photo-thermal catalytic systems. By highlighting the multifield coupling benefits of plasmonic nanomaterials and semiconductor oxides, we summarized and discussed several recently developed photo-thermal catalysts and their catalytic performance in energy production (CO2 conversion and H2 dissociation), environmental protection (VOCs and dyes degradation), and organic compound synthesis (Olefins). Finally, the difficulties and future endeavors related to the design and engineering of photo-thermal catalysts were pointed out to draw the attention of researchers to this sustainable technology used for maximum solar energy utilization.

Advanced municipal wastewater treatment and simultaneous energy/resource recovery via photo(electro)catalysis

Wastewater management and energy/resource recycling have been extensively investigated via photo(electro)catalysis. Although both operation processes are driven effectively by the same interfacial charge, each system is practiced separately since they require very different reaction conditions. In this review, we showcase the recent advancements in photo(electro)catalytic process that enables the wastewater treatment and simultaneous energy/resource recovery (WT-ERR). Various literatures based on photo(electro)catalysis for wastewater treatment coupled with CO2 conversion, H2 production and heavy metal recovery are summarized. Besides, the fundamentals of photo(electro)catalysis and the influencing factors in such synergistic process are also presented. The essential feature of the catalysis lies in effectively utilizing hole oxidation for pollutant degradation and electron reduction for energy/resource recovery. Although in its infancy, the reviewed technology provides new avenue for developing next-generation wastewater treatment process. Moreover, we expect that this review can stimulate intensive researches to rationally design photo(electro)catalytic systems for environmental remediation accompanied with energy and resource recovery.

Dual-functional copper (Cu0/Cu2+)-modified SrTiO3-δ nanosheets with enhanced photothermal catalytic performance for CO2 reduction and H2 evolution

In recent years, metal–semiconductor heterojunctions have been intensively researched in the field of photocatalysis due to the effective spatial separation of photo-induced electron-hole pairs. Here, the dual-functional copper (Cu0/Cu2+)-modified SrTiO3-δ nanosheets (Cu/STCO) are successfully synthesized by a two-step route. First, Cu2+-doped SrTiO3-δ (STCO) nanosheets are synthesized by a hydrothermal method and then Cu0 nanoparticles (NPs) are in situ formed from the STCO under H2 atmosphere at 500 °C. The optimized ratio 6 %-Cu/STCO photocatalyst exhibits the best photothermal catalytic performance for CO2 reduction reaction (CO2RR) and H2 evolution performance. The detailed characterization demonstrate that the Cu2+ dopant extend the light absorption range and the in situ generated Cu0 NPs effectively improve the separation ability of photogenerated charge carriers by forming the Schottky contact with STCO. The excited localized surface plasmon resonance (LSPR) effect of metallic Cu0 in Cu/STCO shows a considerable catalysis performance even under 600 nm monochromatic light irradiation. The density functional theory (DFT) calculations suggest that the Cu/STCO diminishes the barrier of the rate-determining steps of the CO2RR and H2 evolution thus perform the outstanding catalysis ability in two filed. This work presents the synergistic effect of Cu0 and Cu2+ on enhancing the photothermal catalytic performance for CO2RR and H2 evolution and offers a novel strategy to synthesize the metal–semiconductor nanostructures for efficient harnessing of solar energy into fuel.

Comparative study on the electrochemical performance of Sr(Ti0.3Fe0.7)O3-δ fuel electrode in different fuel gases for solid oxide electrochemical cells

Sr(Ti1-xFex)O3−δ (STF) perovskite has been developed as one of the alternatives to Nickel-base fuel electrodes for solid oxide electrochemical cells (SOCs) that can provide good tolerance to redox cycling and fuel impurities. Recent results on STF fuel electrodes present excellent electrochemical performance and outstand stability both under H2 fuel cell mode and H2O electrolysis mode, however, the electrochemical characteristics in other fuel gases, such as CO, CO–H2 mixture, CH4, and CO–CO2 mixture have not been investigated. Herein, we report the electrochemical performance of Sr(Ti0.3Fe0.7)O3−δ fuel electrode on La0.8Sr0.2MnO3−δ-Zr0.92Y0.16O2−δ (LSM-YSZ) oxygen electrode supported SOCs with thin YSZ electrolyte using different fuel gases. At 800 °C, the peak power density slightly decreased from 0.9 W/cm2 in wet H2 to 0.68 W/cm2 in wet CO under fuel cell mode. However, the cell only showed a peak power density of 0.27 W/cm2 at 800 °C in wet CH4, reaching 0.75 W/cm2 at 850 °C, when the open-circuit voltage increased from 0.9 V to 1.02 V. STF fuel electrode exhibited much worse CO2 electrolysis performance than steam electrolysis, especially in high CO2 concentration due to the increased ohmic resistance and electrode polarization resistance.

A Review on MXene Synthesis, Stability, and Photocatalytic Applications.

Photocatalytic water splitting, CO2 reduction, and pollutant degradation have emerged as promising strategies to remedy the existing environmental and energy crises. However, grafting of expensive and less abundant noble-metal cocatalysts on photocatalyst materials is a mandatory practice to achieve enhanced photocatalytic performance owing to the ability of the cocatalysts to extract electrons efficiently from the photocatalyst and enable rapid/enhanced catalytic reaction. Hence, developing highly efficient, inexpensive, and noble-metal-free cocatalysts composed of earth-abundant elements is considered as a noteworthy step toward considering photocatalysis as a more economical strategy. Recently, MXenes (two-dimensional (2D) transition-metal carbides, nitrides, and carbonitrides) have shown huge potential as alternatives for noble-metal cocatalysts. MXenes have several excellent properties, including atomically thin 2D morphology, metallic electrical conductivity, hydrophilic surface, and high specific surface area. In addition, they exhibit Gibbs free energy of intermediate H atom adsorption as close to zero and less than that of a commercial Pt-based cocatalyst, a Fermi level position above the H2 generation potential, and an excellent ability to capture and activate CO2 molecules. Therefore, there is a growing interest in MXene-based photocatalyst materials for various photocatalytic events. In this review, we focus on the recent advances in the synthesis of MXenes with 2D and 0D morphologies, the stability of MXenes, and MXene-based photocatalysts for H2 evolution, CO2 reduction, and pollutant degradation. The existing challenges and the possible future directions to enhance the photocatalytic performance of MXene-based photocatalysts are also discussed.

A unique Janus PdZn-Co catalyst for enhanced photocatalytic syngas production from CO2 and H2O

The development of excellent catalyst to achieve photocatalytic syngas production from CO2 and H2O is a prospective and sustainable strategy to alleviate environment and energy crisis. In this study, a unique Janus PdZn-Co catalyst is prepared by annealed the Pd/IRMOF-3(Co, Zn) precursor. Due to the strong interaction, the electron transfers from PdZn terminal to Co terminal in the Janus structure. The electron-received Co terminal facilitates Co sites coordinate with the electrophilic C atom of CO2 and the electron-donated PdZn center is easier to coordinate with nucleophilic O atoms of H2O or CO bonds. The charge redistribution enhances the absorption of CO2 and H2O, which promotes H2 evolution and CO production. In addition, the carbon shell effectively suppresses the metal core agglomeration and facilitates the electron transmission from photosensitizer to metallic active sites. Meanwhile, the ratio of CO/H2 can be regulated (∼3:1 to 2:1) by adjusting the proportion of Co and PdZn. The Janus structure and graphite carbon synergistically play a profound impact on improving the photocatalytic performance. The optimized PdZn-Co catalyst exhibits a superior photocatalytic CO production rate (20.03 µmol/h) and the H2 generation rate (9.90 µmol/h) with a ratio of CO/H2 = 2.02.

Sorption-enhanced steam gasification of fine coal waste for fuel producing

Improving the quality of syngas from fine coal waste using the sorption-enhanced gasification process is a novel technology in the production of H2. The effect of CaO on CO2 absorption and H2 increase in the steam fine coal gasification process was determined in a fixed bed gasifier. The steam gasification process took place at 650 °C using bentonite and CaO as catalysts and absorbents. Steam increased the H2 concentration in the syngas to 58 vol%. In-situ CO2 absorption is more effective with the addition of CaO. The maximum percentage of CO2 was absorbed when the Ca/C ratio 2 was 78.33 %. The H2 content in the syngas after the CO2 was absorbed increased rapidly to 75.80 vol% at a Ca-to-carbon-mole ratio (Ca/C) of 1.5 and a steam-to-feedstock ratio (S/F) of 1.5. CaO did not produce significant results for low heating value (LHV) or cold gas efficiency (CGE), with results of 12 MJ/Nm3 and 44.53 %. The dominant water gas shift reaction due to the influence of steam and CaO increased H2/CO up to 9.11, which made the syngas from this work suitable for Fischer–Tropsch synthesis.

Off-Gas System Scale-Up of HIsarna Iron-Making Process: A CFD-Based Approach

For all industrial applications, predicting system characteristics and behavior plays a vital role before constructing costly and complex multi-physic systems. Correct and reliable predictions become even more important once the aim is to go from small- to large-scale processes to establish an industrial demonstrations. In this study, a CFD-based scale-up of HIsarna off-gas system based on the Eulerian–Lagrangian approach is investigated and detailed step in scale-up procedure is discussed. A three-dimensional CFD model is developed and validated based on the available pilot scale data and used to design and scale up the post-combustion chamber (also known as reflux chamber). Detailed kinetics for volumetric and gas–solid reactions are incorporated in validated CFD model with a special attention to the wall boundary condition and modeling. The effect of reflux chamber geometry, oxygen injection ports, oxygen injection flowrate, isolation wall thickness, and inlet flue gas composition on different system characteristics such as heat loss through the wall, CO–H2–carbon mixture conversion, flue gas, and wall temperature are investigated. The aim of the scaled up geometry, like pilot scale, is to achieve full combustion of unwanted species inside the reflux chamber to assure zero emissions from the off-gas system. Compared to the pilot scale, the scaled up reflux chamber is capable of handling and removing higher amount of unwanted species coming from the main reactor and therefore lower CO–H2 and carbon particle emissions, mainly due to a larger size which provides larger volume and residence time for volumetric and gas–solid reaction to proceed.

The performance of exchange-correlation functionals in describing electron density parameters of saddle point structures along chemical reactions.

This work is focused on evaluating the performance of exchange-correlation functionals from density functional theory in providing descriptor values derived from the electron density of saddle point structures (transition states) in chemical reactions. The properties investigated were obtained from the quantum theory of atoms in molecules, including atomic charges and electron density topological data at the bond critical points. In addition, parameters from the Interacting quantum atom energy partition were used as well in this comparative study. The reference values are attained in coupled cluster calculations with iterative single and double excitations (CCSD). Six elementary reactions are considered here: CO + H2 ↔H2 CO, CO + H2 O↔HCOOH, HCN↔HNC, H + F2 ↔HF + F, H + N2 ↔HN2 , and H + CO↔HCO. In general, the BB1K functional (hybrid-meta-generalized gradient approximation) provides the best description of these properties. Our study indicates that an intermediate percentage of nonlocal exact exchange, around 40%-55% (perhaps even larger), is probably required for attaining more accurate values with actual functionals, although this condition is not able of explaining all the trends observed.

Performance limits of neural networks for optimizing an adsorption process for hydrogen purification and CO2 capture

In this work, we use surrogate models to accelerate the optimization of an adsorption process for H2 purification and CO2 capture within the context of fossil-based low-carbon H2 production. A one dimensional column model was used to generate a training set for different feed compositions with up to four impurities and for varying process conditions. Subsequently, an artificial neural network (ANN) surrogate model was trained for six key performance indicators, achieving adjusted R2 values over 0.999 for all indicators. Finally, the ANN was used for the constrained optimization of the H2 separation performance and of the process performance (energy consumption and productivity), and the results were compared to full model optimization results. The agreement is very good for the H2 separation performance, and in the case of low H2 purity targets (99%) also for the process performance. For higher H2 purities, however, the energy-productivity Pareto front features a very high sensitivity toward the H2 purity constraint, and even small deviations in H2 purity between full model and ANN surrogate model can translate to big deviations in the energy-productivity Pareto front. This is particularly pronounced for poorly sampled input regions at the edge of the sampling domain, for example for a binary H2-CO2 feed. If the ANN surrogate model is used at such edges of the sampling domain, additional sampling is required in this region to increase its accuracy. For all other cases, the deviations between the full model and the ANN surrogate model regarding the minimum energy consumption (or the maximum productivity) were well below 5%, showing that the ANN can be used with good accuracy instead of the full model.

Experimental and theoretical insights into an enhanced CO2 methanation mechanism over a Ru-based catalyst

Converting excessive CO2 emissions from industrial operation into methane (CH4) is critical for the remediation of global warming. However, this reaction requires a high temperature to overcome the high thermodynamic stability of CO2. The development of efficient catalysts for the CO2 methanation reaction at low temperature remains challenging. Here we report that when a TiO2 photothermal catalyst is loaded with Ru nanoparticles, the CO2 to CH4 conversion efficiency is markedly enhanced under light illumination. In fact, the CO2 performance was enhanced fourfold and twofold from those of the traditional thermal catalytic reaction at 200 °C and 250 °C, respectively. In-situ DRIFTS analysis revealed that light irradiation accelerates the transition of bicarbonate to formates via light-induced charge carriers. Moreover, theoretical calculations revealed that photo-induced electron transfer effectively promotes H2 dissociation and CO2 activation on the Ru atoms. This work provides new theoretical insights into CO2 activation and methanation under light illumination.

Understanding the role of K on PtCo/Al2O3 for preferential oxidation of CO in H2

CO preferential oxidation reaction (CO-PROX) can effectively eliminate CO in H2 rich atmosphere to avoid CO poison the Pt anode of Proton Exchange Membrane Fuel Cell (PEMFC). To match the operation temperature window for PEMFC, PtCo nanoparticles supported on K modified Al2O3 (PtCo/K–Al2O3) were prepared to promote CO-PROX activity. The addition of K species weakened the interaction between PtCo nanoparticle and support, which improved the dispersion of Pt particles and redox property of PtCo/Al2O3. It also facilitated the formation of Pt3Co species and active surface −OH groups, which were involved in CO-PROX reaction. According to in situ DRIFTS spectra, HCO3− and HCOO− were intermediates of PtCo/K–Al2O3 catalyzed CO-PROX at low temperature and high temperature, respectively. Thus, the addition of 1 wt% K to PtCo/Al2O3 (PtCo/1K–Al2O3) could completely oxidize CO in the temperature range of 127–230 °C with O2 selectivity at 50%. The 100% CO conversion temperature window of PtCo/1K–Al2O3 is expanded by 100 °C in comparison of PtCo/Al2O3.