Surface Lattice Oxygen Research Articles

Electrochemical Etching Switches Electrocatalytic Oxygen Evolution Pathway of IrOx /Y2 O3 from Adsorbate Evolution Mechanism to Lattice-Oxygen-Mediated Mechanism.

Oxygen evolution reaction (OER) plays key roles in electrochemical energy conversion devices. Recent advances have demonstrated that OER catalysts through lattice oxygen-mediated mechanism (LOM) can bypass the scaling relation-induced limitations on those catalysts through adsorbate evolution mechanism (AEM). Among various catalysts, IrOx , the most promising OER catalyst, suffers from low activities for its AEM pathway. Here, it is demonstrated that a pre-electrochemical acidic etching treatments on the hybrids of IrOx and Y2 O3 (IrOx /Y2 O3 ) switch the AEM-dominated OER pathway to LOM-dominated one in alkali electrolyte, delivering a high performance with a low overpotential of 223mV at 10mA cm-2 and a long-term stability. Mechanism investigations suggest that the pre-electrochemical etching treatments create more oxygen vacancies in catalysts due to the dissolution of yttrium and then provide highly active surface lattice oxygen for participating OER, thereby enabling the LOM-dominated pathway and resulting in a significantly increased OER activity in basic electrolyte.

Creation of surface frustrated Lewis pairs on high-entropy spinel nanocrystals that boosts catalytic transfer hydrogenation reaction

Creating frustrated Lewis pairs (FLPs) on stable high-entropy oxides (HEOs) is a new challenge, and also an uncultivated field in catalysis. Herein, holey layered HEO spinel nanocrystals with rich FLPs were synthesized via a temperature-driven topological transition. The FLPs on the surface of HEO spinel nanocrystals are created by oxygen vacancies (Lewis acid sites) and proximal surface hydroxyls or surface lattice oxygen (Lewis base sites). Rich FLPs furnish HEO nanocrystals a superior activity towards the catalytic transfer hydrogenation reaction of biomass-derived carbonyl compounds at mild conditions. The active regions in between FLPs provide a strong driving force for dissociating alcohols and activating carbonyl groups of substrates, as evidenced by the attenuated total reflectance-infrared spectroscopy (ATR-IR) analysis, which enhances the catalytic activity. This work develops a new kind of hydrogenation catalysts and provides a perspective for creating solid FLPs.

Exceptionally stable CePO4 and RuO2 contributing to catalytic oxidation of 1,2-dichloroethane on Co3O4 catalysts: Complete inhibition of chlorinated byproducts

Highly toxic, reactive and refractory chlorinated VOCs (Cl-VOCs) is urgent for purification by the most favoured catalytic oxidation technique, however, the formation of polychlorinated byproducts is huge obstacle for most catalysts. Here, nanorods assembled monoclinic CePO4 microspheres were synthesized and used as the support of highly active but low-selective Co3O4 for catalytic oxidation of Cl-VOCs. The prepared Co3O4/CePO4 using ascorbic acid (AA) as a chelating agent presented a high activity and low selectivity of vinyl chloride (VC) for catalytic oxidation of 1,2-dichloroethane (DCE) due to the high dispersion of Co3O4, compared with bulk Co3O4 and Co3O4/SiO2, possible polychlorinated byproducts were completely inhibited in the presence of CePO4 support. The co-introduction of RuO2 further suppressed the formation of VC as a representative dechlorinated byproduct owing to the enhanced redox ability and migration of surface lattice oxygen, below 0.5% VC selectivity was detected on the optimized RuCoOx/CePO4 and completely disappeared above 275 °C. Moreover, RuCoOx/CePO4 also revealed the superior versatility, durability and thermal stability as well as the outstanding resistance to CO2, H2O and sulfur. The restraint of polychlorinated byproducts also can be achieved by other phosphates besides CePO4 and attributed to the strong coordination effect and electron-withdrawing function of PO43-. This work was contributed to further understand the inhibition of chlorinated byproducts for catalytic oxidation of Cl-VOCs and rationally design full-featured catalysts.

Lattice Oxygen Redox Reversibility Modulation in Enhancing the Cycling Stability of Li‐Rich Cathode Materials

AbstractThe practical application of lithium‐rich layered oxides is prohibited by the drawbacks such as severe capacity and voltage degradation resulting from unstable oxygen redox environment and the accompanied irreversible oxygen release. Herein, a facile and effective strategy is proposed to regulate the oxygen redox chemistry via foreign Fe doping and its induced intrinsic transition metal (TM) doping as well as the in situ constructed spinel surface layer. The Fe doping, together with the induced intrinsic TM dual doping, can stabilize the lattice oxygen in the bulk due to the formed stronger FeO bond, and restrain the irreversible TM migration and then the undesirable phase transformation. More importantly, thermodynamical energy barrier of oxygen activation is dramatically decreased by the O 2p–Fe 3d charge‐transfer, allowing stable oxygen redox activity. And the pre‐constructed spinel layer can effectively stabilize the surface lattice oxygen and suppress harmful interfacial side‐reactions. Such a simple optimizing method make the modified cathode exhibit a high specific capacity of 298 mAh g−1 at 0.2 C, outstanding cycling stability with a superior capacity and voltage retentions of 92.5% and 90.8%, respectively, after 400 cycles at 1 C. This study provides a new direction for developing advanced Li‐ion batteries.

Engineering Ag-O-Mn bridges with enhanced oxygen mobility over Ag substituted LaMnO3 perovskite catalyst for robustly boosting toluene combustion

Perovskite oxide, as a promising candidate for volatile organic compounds combustion, is incapable in practical application at present due to its low intrinsic activity resulting from inadequate active oxygen species. However, balancing the concentration of active oxygen species and robust structure for perovskite oxide is still challenging. Herein, an efficient perovskite-based catalyst (denoted as TA-La0.9Ag0.1MnO3) was constructed through Ag substitution and subsequently tartaric acid etching of LaMnO3, which exhibits robustly boosted catalytic performance for toluene combustion compared with pristine LaMnO3, causing a ∼100 °C lower T90. In this study, Ag substitution could weaken the La-O hybridization, which effectively facilitates La cations removal by subsequent acid etching, thus sufficiently exposing active Ag and Mn species and generating more surface lattice oxygen, but also constructs Ag-Mn-O bridges within the matrix of Ag substituted LaMnO3. Acid etching enables the activation of Ag-O-Mn bridges with strong electron transfer ability from O to Ag atom, promoting the mobility of lattice oxygen, and consequently the low-temperature oxidation ability. Additionally, the exposed Ag and Mn as Lewis acid sites can effectively improve the adsorption capacity toward toluene molecules, which synergistically facilitates the toluene abatement. Notably, TA-La0.9Ag0.1MnO3 also exhibits superb long-term stability, water-resistance, and high thermal stability up to 650 °C.

Contributions of Surface Oxygen Species and Photoinduced Holes on Photothermocatalytic Toluene Oxidation over CeO2–MgO

To reveal the activity enhancement mechanism of volatile organic compounds (VOC) oxidation reaction, is vital for developing high-efficiency and cost-effective photothermocatalytic materials. Herein, porous and low-cost CeO2–MgO composite oxides were simply constructed via the solution combustion method and applied for toluene photothermocatalytic oxidation. The conversion rate for 1500 ppm of toluene over the optimized sample could reach 90% under the photothermocatalytic process at 330 °C and a gas hourly space velocity of 60,000 mL·g–1·h–1. Both gas phase oxygen and reactive oxygen species (ROS) played the dominant role in the photothermocatalytic activity while the total contribution rate of photoinduced holes and surface lattice oxygen was 25% to the activity. In situ Fourier transform infrared and electron paramagnetic resonance results revealed that the synergistic photothermo activation of molecular oxygen accelerated the low-temperature ROS formation. Under irradiation, photoinduced electrons could benefit the efficient transfer from superoxide radicals to peroxide radicals on material. Hence, it provides not only a comprehensive understanding on the activity enhancement mechanism at the molecular level but also a theoretical reference for designing objective catalysts for VOC abatement.

Revealing the equilibrium relationship between lattice oxygen mobility and styrene removal: Sources of adsorption and activation by in situ experiments

Copper-manganese composite oxides have been extensively researched for the catalytic oxidation of volatile organic compounds (VOCs), but there is little understanding of the adsorption and activation of VOCs over these compounds. In this work, a series of amorphous Cu-Mn binary oxides with varying Cu/Mn ratios were prepared to explore their catalytic performance and the species involved in the adsorption and activation of styrene (C8H8). It was found that Cu1Mn5Ox demonstrated better catalytic activity among the four samples, better stability and water resistance due to the presence of more structural flaws, weaker Mn-O bonds and more surface lattice oxygen species. In situ designed experiments showed that the adsorbed oxygen species, O2, lattice oxygen, and copper species all played roles in the adsorption and activation of C8H8 at low temperatures. The degradation route for C8H8 was revealed by in situ DRIFTS, and benzoic acid decomposition was identified as the rate-limiting step of C8H8 degradation. This work provides a novel technique for regulating the synergistic adsorption and catalytic ability of amorphous bimetallic oxides to remove VOCs.

Insights into the role of sensitive surface lattice oxygen species on promoting methane conversion

Insights into the role of sensitive surface lattice oxygen species on promoting methane conversion

Constructing γ-MnO2 with abundant oxygen vacancies by a chelating agent-assistant strategy to achieve high-efficient conversion of NO to NO2

To date, the exploitation of non-noble materials of high-efficiency and low-temperature conversion of NO to NO2 still existed as a challenging task due to high cost of current Pt-based commercial catalysts. Herein, we employed a chelating agent-assistant strategy to regulate the content of oxygen vacancy over γ-MnO2 catalysts, which were further used for NO oxidation. Benefiting from the structure-directing effect of tartaric acid, the resultant locus-shaped γ-MnO2 catalyst with abundant oxygen vacancies showed a remarkable low-temperature catalytic activity (T50 and T92 of 127 and 225 °C; respectively), which was superior to unmodified γ-MnO2 sample (T50 at 189 °C) and those recently reported good-performing NO oxidation catalysts. An array of characterization results revealed that an extended capping by means of chelating agents could effectively weaken the MnO bond strength and promote the formation of oxygen vacancy (OVs), thus tremendously increase the amount of surface-active oxygen species. Moreover, theoretical calculation demonstrated that an enriched OVs concentration could enhance the reactivity of surface lattice oxygen by reducing the formation energy of OVs, further accelerating reaction rate of the adsorption/activation of O2 molecules and thus bringing about an outstanding low-temperature catalytic activity. This study highlighted the potential of chelating agents in the design of high-efficient catalysts for environmental remediation and beyond.

Elucidating the Role of Surface Ce4+ and Oxygen Vacancies of CeO2 in the Direct Synthesis of Dimethyl Carbonate from CO2 and Methanol.

Cerium dioxide (CeO2) was pretreated with reduction and reoxidation under different conditions in order to elucidate the role of surface Ce4+ and oxygen vacancies in the catalytic activity for direct synthesis of dimethyl carbonate (DMC) from CO2 and methanol. The corresponding catalysts were comprehensively characterized using N2 physisorption, XRD, TEM, XPS, TPD, and CO2-FTIR. The results indicated that reduction treatment promotes the conversion of Ce4+ to Ce3+ and improves the concentration of surface oxygen vacancies, while reoxidation treatment facilitates the conversion of Ce3+ to Ce4+ and decreases the concentration of surface oxygen vacancies. The catalytic activity was linear with the number of moderate acidic/basic sites. The surface Ce4+ rather than oxygen vacancies, as Lewis acid sites, promoted the adsorption of CO2 and the formation of active bidentate carbonates. The number of moderate basic sites and the catalytic activity were positively correlated with the surface concentration of Ce4+ but negatively correlated with the surface concentration of oxygen vacancies. The surface Ce4+ and lattice oxygen were active Lewis acid and base sites respectively for CeO2 catalyst, while surface oxygen vacancy and lattice oxygen were active Lewis acid and base sites, respectively, for metal-doped CeO2 catalysts. This may result from the different natures of oxygen vacancies in CeO2 and metal-doped CeO2 catalysts.

Synergy of Oxygen Vacancies and Ni0 Species to Promote the Stability of a Ni/ZrO2 Catalyst for Dry Reforming of Methane at Low Temperatures

Low-temperature dry reforming of methane (DRM) can avoid the sintering of nickel and reduce the cost of the process. However, inefficient activation of CO2 and oxidization of Ni0 hamper the catalytic performance of Ni-based catalysts at low temperatures. Herein, a Ni/ZrO2 catalyst was prepared and used in the DRM reaction, which exhibited stable activity at low temperatures (400, 320 and 300 °C) for 10 h, with CH4 and CO2 turnover frequencies of 0.26 and 0.18 s–1 at 320 °C, respectively. The presence of Ni0 species and oxygen vacancies promotes the activation of CO2 at 300 °C, proved by CO2 temperature-programmed oxidation (CO2-TPO). Combined with O2 temperature-programmed decomposition (O2-TPD), C18O2-DRM, in situ X-ray photoelectron spectroscopy (XPS), and diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) results, after CH4 decomposition on the Ni0 site, the resultant C would react with nearby surface oxygen species and lattice oxygen species of ZrO2, forming CO and an oxygen vacancy. The oxygen vacancy nearby Ni0 species with more electron transfer would promote the activation of CO2. This work highlights the importance of CO2 activation and emphasizes the key role of the synergistic effect between Ni0 species and the oxygen vacancy in enhancing the stability of catalysts over low-temperature DRM reactions.

Promoting mechanism of CuO on catalytic performance of CeFe catalyst for simultaneous removal of NOx and CO

Nitrogen oxides (NOx) and carbon monoxide (CO) coexisted in numerous industrial waste gases. And selective catalytic reduction of NOx with ammonia (NH3-SCR) and CO catalytic oxidation were considered as the effective technologies for simultaneous elimination of NOx and CO, respectively. However, an efficient bifunctional catalyst was crucial for achieving simultaneous removal of NOx and CO. Herein, we developed a series of Cu-modified CeFe catalysts for simultaneous removal of NOx and CO. The results demonstrated that 5Cu-CeFe catalyst presented the best catalytic performance, achieving approximately 81% NOx removal efficiency and nearly 99% CO conversion rate at 200 °C under a gas houely space velocity of 90,000 h−1. The XPS analysis demonstrated that copper oxides played a critical role in promoting the formation of Ce3+ and Oβ, thereby facilitating the NH3-SCR catalytic performance and CO catalytic oxidation. Moreover, the copper oxide modification of CeFe catalyst attained a trade-off between the surface acidity and redox ability, resulting in improving adsorption and activition capacity of the reactant gases. In situ DRIFTS experiments revealed that the NH3-SCR process primarily obeyed the Eley-Rideal (E-R) pathway over both CeFe and 5Cu-CeFe catalysts, while Langmuir-Hinshelwood (L-H) pathway hardly participated in NH3-SCR process. The presence of Cu+–CO species and surface lattice oxygen was crucial for CO oxidation, and both Mars-van Krevelen (M−K) and L-H pathways might be involved in the CO catalytic oxidation process over 5Cu-CeFe catalyst.

Synergetic C–H bond activation and C–O formation on CuOx facilities facile conversion of methane to methanol

Direct methane to methanol conversion is desirable but difficult to implement due to the inertness of methane and unattainable matching oxidant. The capability of Cu oxides releasing lattice oxygen makes it a potential oxidant to facilitate the conversion. Herein, the mechanism of methane to methanol on the surfaces of CuOx has been studied using density functional theory calculations. Heterolytic cleavage of the C–H bond is preferred at the Cu–O site whereas methanol formation from dissociated CH3 and H on surface O can take place over either Cu–O or O–O site. On CuO(1¯1 1), methane activation at the Cu–O site and methanol formation over the O–O site synergistically enable the selective oxidation of methane to methanol. In contrast, the formation of methanol on the O-deficient surfaces is a result of direct coupling of CH3 on Cu and OH formed from of H adsorbed on the surface O site. Microkinetics analysis confirms the synergistic effect of Cu–O and O–O on CuO(1¯1 1) for methanol formation in a temperature range of 473–648 K. These findings demonstrate the feasibility of selective oxidation of methane to methanol with the surface lattice oxygen of CuOx and help to design the CuOx-based oxygen carriers and/or catalysts.

Solid solution F-MnxCo3-xO4 ultrathin nanosheets: Highly active and selective catalyst for oxidation of 5-hydroxymethyl furfural

Ultrathin nanosheets (F-MnCo) with a thickness of ∼1.7 nm are synthesized by incubation of NaF, Co(CH3COO)2, and KMnO4 in aqueous solution at room temperature. F-MnCo is comprised of the self-assembled CoOOH and Co(OH)F nanocrystals and highly dispersed MnO2. Through the calcination at 230 °C, CoOOH and Co(OH)F are pyrolyzed to form F-Co3O4, with manganese being concomitantly embedded in the lattice of F-Co3O4. The synthesized F-MnxCo3-xO4 is a solid solution, exhibiting a structure of ultrathin nanosheets with a thickness of ∼1.1 nm. F-MnxCo3-xO4 has been applied as catalyst for the oxidations of 5-hydroxymethyl furfural (HMF) and alcohols, exhibiting an excellent catalytic activity and a high aldehyde selectivity. The ultrathin nanosheets can facilitate mass transfer of reactants and provide more open active sites. High proportion of surface lattice oxygen, abundant oxygen vacancy, excellent oxygen mobility, and uniformly embedded manganese in the lattice also contribute to F-MnxCo3-xO4 exhibiting the excellent catalytic activity.

Synergistic structure of LiFeO2 and Fe2O3 layers with electrostatic shielding effect to suppress surface lattice oxygen release of Ni-rich cathode

The Ni-rich cathodes used for lithium-ion batteries (LIBs) suffer from severe surface side reactions, slow kinetics, and microcracks during long-term cycling. To address these problems, a dual-modified protective coating consisting of LiFeO2&Fe2O3 layers (denoted as LFO) was fabricated on the surface of the cathode material LiNi0.8Co0.1Mn0.1O2 (NCM811) by capturing the lithium impurities in the electrolyte solution using an electric field. The LiFeO2 layer acts as an ionic conductor, accelerating interfacial Li+ transport, and exhibits a synergistic effect with the bulk material during the charging/discharging process. The Fe2O3 layer, which contains abundant oxygen vacancies, acts as an electrostatic shielding layer and effectively inhibits the outward migration of Oα− (α < 2), thus improving the structural stability. Hence, the interface-protected NCM@LFO3 cathode showed excellent cycling stability (capacity retention of 82.4% after 600 cycles at 1 C) and even at a high cut-off voltage of 4.5 V (capacity retention of 88.9 % after 200 cycles at 1 C).

Oxygen activation-boosted manganese oxide with unique interface for chlorobenzene oxidation: Unveiling the roles and dynamic variation of active oxygen species in heterogeneous catalytic oxidation process

In-depth study of active oxygen species (AOS) is essential to heterogeneous catalytic oxidation techniques. Herein, a facile strategy of constructing dual-phase MnOx with unique Mn2O3Mn3O4 interface is reported for chlorobenzene (CB) catalytic oxidation. The interface induces lattice distortion and generates oxygen vacancies, promoting the formation and mobility of surface adsorbed oxygen (Oads) and surface lattice oxygen (Olatt), while the surface acidity and CB adsorption capacity are also enhanced. Thereby, MnOx catalyst exhibits superior activity and lower activation energy (41.7 kJ/mol), with the CB total degradation temperature decreasing by ca. 40 °C. Noteworthily, the dynamic variation of AOS in CB oxidation is unveiled by in situ techniques combined with isotope labelling, where Oads and Olatt are determined to function as AOS at low and high temperatures (over 300 °C), respectively. Furthermore, the reaction pathway and the rate-determining step (cleavage of aromatic ring) are revealed by systematic mechanism study.

Revealing the Excellent Low-Temperature Activity of the Fe1–xCexOδ-S Catalyst for NH3-SCR: Improvement of the Lattice Oxygen Mobility

The development of selective catalytic reduction catalysts by NH3(NH3-SCR) with excellent low-temperature activity and a wide temperature window is highly demanded but is still very challenging for the elimination of NOx emission from vehicle exhaust. Herein, a series of sulfated modified iron-cerium composite oxide Fe1-xCexOδ-S catalysts were synthesized. Among them, the Fe0.79Ce0.21Oδ-S catalyst achieved the highest NOx conversion of more than 80% at temperatures of 175-375 °C under a gas hourly space velocity of 100000 h-1. Sulfation formed a large amount of sulfate on the surface of the catalyst and provided rich Brønsted acid sites, thus enhancing its NH3 adsorption capacity and improving the overall NOx conversion efficiency. The introduction of Ce is the main determining factor in regulating the low-temperature activity of the catalyst by modulating its redox ability. Further investigation found that there is a strong interaction between Fe and Ce, which changed the electron density around the Fe ions in the Fe0.79Ce0.21Oδ-S catalyst. This weakened the strength of the Fe-O bond and improved the lattice oxygen mobility of the catalyst. During the reaction, the iron-cerium composite oxide catalyst showed higher surface lattice oxygen activity and a faster replenishment rate of bulk lattice oxygen. This significantly improved the adsorption and activation of NOx species and the activation of NH3 species on the catalyst surface, thus leading to the superior low-temperature activity of the catalyst.

Inhibition of Structural Transformation and Surface Lattice Oxygen Activity for Excellent Stability Li-Rich Mn-Based Layered Oxides

Li-rich Mn-based layered oxides (LLOs) are one of the most promising cathode materials, which have exceptional anionic redox activity and a capacity that surpasses 250 mA h/g. However, the change from a layered structure to a spinel structure and unstable anionic redox are accompanied by voltage attenuation, poor rate performance, and problematic capacity. The technique of stabilizing the crystal structure and reducing the surface oxygen activity is proposed in this paper. A coating layer and highly concentrated oxygen vacancies are developed on the material's surface, according to scanning electron microscopy, transmission electron microscopy, and X-ray photoelectron spectroscopy. In situ EIS shows that structural transformation and oxygen release are inhibited during the first charge and discharge. Optimized 3@LRMA has an average attenuation voltage of 0.55 mV per cycle (vs 1.7 mV) and a capacity retention rate of 93.4% after 200 cycles (vs 52.8%). Postmortem analysis indicates that the successful doping of Al ions into the crystal structure effectively inhibits the structural alteration of the cycling process. The addition of oxygen vacancies reduces the surface lattice's redox activity. Additionally, surface structure deterioration is successfully halted by N- and Cl-doped carbon coating. This finding highlights the significance of lowering the surface lattice oxygen activity and preventing structural alteration, and it offers a workable solution to increase the LLO stability.

HCHO oxidation over the δ-MnO2 catalyst: Enhancing oxidative activities of surface lattice oxygen and surface adsorbed oxygen by weakening Mn-O bond

The usages of HCHO in construction and decoration materials lead to serious indoor air pollution, removing the indoor HCHO to improve air quality is urgently required. In this work, we developed a new procedure to synthesis ultra-thin nanosheet δ-MnO2 without using traditional templates. The Mn-O bond was much weaker in the ultra-thin nanosheet δ-MnO2 than those in the β- and γ-MnO2. As a consequence, surface oxygen lattice of the δ-MnO2 was the most removable, generating the most oxygen vacancy on the surface. The oxidative ability of the lattice oxygen was the most enhanced, active surface adsorbed oxygen species were the most present on the δ-MnO2 surface. These contributed to an unexpected performance that 100 ppm HCHO was fully oxidized at 35–45 °C depending on the relative humidity between 10 and 50% at high space velocity of 300 L/(gh). When compared with HCHO oxidation performance of MnO2 in literatures, the current ultra-thin nanosheet δ-MnO2 lists the most active HCHO oxidation catalyst as regards to the lowest activation energy, the lowest temperature of full HCHO conversion and the highest rate of HCHO oxidation, giving the most promising potential application for practical indoor HCHO elimination.

Interface engineering of Mn3O4/Co3O4 S-scheme heterojunctions to enhance the photothermal catalytic degradation of toluene

Transition metal oxides have high photothermal conversion capacity and excellent thermal catalytic activity, and their photothermal catalytic ability can be further improved by reasonably inducing the photoelectric effect of semiconductors. Herein, Mn3O4/Co3O4 composites with S-scheme heterojunctions were fabricated for photothermal catalytic degradation of toluene under ultraviolet-visible (UV-Vis) light irradiation. The distinct hetero-interface of Mn3O4/Co3O4 effectively increases the specific surface area and promotes the formation of oxygen vacancies, thus facilitating the generation of reactive oxygen species and migration of surface lattice oxygen. Theoretical calculations and photoelectrochemical characterization demonstrate the existence of a built-in electric field and energy band bending at the interface of Mn3O4/Co3O4, which optimizes the photogenerated carriers’ transfer path and retains a higher redox potential. Under UV-Vis light irradiation, the rapid transfer of electrons between interfaces promotes the generation of more reactive radicals, and the Mn3O4/Co3O4 shows a substantial improvement in the removal efficiency of toluene (74.7%) compared to single metal oxides (53.3% and 47.5%). Moreover, the possible photothermal catalytic reaction pathways of toluene over Mn3O4/Co3O4 were also investigated by in situ DRIFTS. The present work offers valuable guidance toward the design and fabrication of efficient narrow-band semiconductor heterojunction photothermal catalysts and provides deeper insights into the mechanism of photothermal catalytic degradation of toluene.