Production Of Oxygen Vacancies Research Articles

Anisotropic ferroelectric-shaped hysteresis loop and colossal permittivity in thermally treated rutile TiO2 single crystals

Space charge polarization is an unavoidable phenomenon in electronic components that leads to deterioration of electrical response. Hence manipulation and utilization of space charge polarization to improve electrical properties is a phenomenal task. In the present study, heating treatment produces oxygen vacancies, resulting in the crystal structures (i.e., modulated structure and intergrowth structure) and band gap are anisotropic, which in turn leads to anisotropic nonlinear polarization behavior and colossal permittivity. Quantitative analysis of the atomic-scale structure confirms the modulated structure and intergrowth structure are anisotropic. A modulated structure along a axis of rutile TiO2 with a width of six times that of a rutile crystal cell a is constructed through an intergrowth structure between rutile and srilankite TiO2 phases in rutile TiO2 single crystals, wherein space charges at the intergrowth structure give rise to ferroelectric-shaped hysteresis in heated TiO2 single crystals along [001] direction. Impedance spectra display three kinds of space charge polarizations (modulated structure, intergrowth structure, and electrode non-ohmic contact) contribute to the colossal permittivity along [001] direction. The space charge polarizations contribute to a colossal permittivity (∼45,000), high resistivity (∼1010 Ω cm), and ferroelectric-shaped P-E loop (remanent polarization: ∼17.1 μC/cm2, coercive field: ∼4.3 kV/cm) in the heated TiO2 single crystal along [001] direction, while a linear polarization behavior and permittivity value of 120 are obtained along [100] direction. The findings provide guidance for the utilization of space charge polarization in dielectric materials.

PVP-assisted in-situ self-assembly hierarchical BiOCl with oxygen vacancies for efficient photocatalytic oxidation of cyclohexane under air in solvent-free conditions

Cyclohexane (CHA) selective oxidation reactions are crucial in designing advanced organic intermediates but suffering from very challenges as the products of KA oil (cyclohexanol and cyclohexanone) are more readily oxidized to CO2. Herein, we report that a polyvinylpyrrolidone (PVP) coating of fluffy self-assembled morphology of BiOCl by nanosheets with exposed {001} facets are synthesized via the solvothermal method. Moreover, the as-synthesized hierarchical BiOCl exhibits a significant presence of in-situ produced oxygen vacancies during photocatalysis, thereby facilitating efficient CHA oxidation to KA oil with air as an oxidant in solvent-free at room temperature. The crystallinity, micromorphology, and electronic structure of BiOCl can be significantly influenced by the concentration of NH4Cl and PVP. In the photocatalytic oxidation, oxygen vacancies act as traps to inhibit electrons and holes recombination and adsorb-activate the oxygen molecule, producing h+ and ·O2− radical to achieve 466.7 μmol of KA oil (340.8 μmol of cyclohexanone and 125.9 μmol of cyclohexanol) with a selectivity of 93.9 %. The ∙OH radicals play a predominant role in the production of CHA-one. After conducting 5 experimental cycles, a consistent yield of 92 % towards KA oil and unchanged selectivity can still be maintained. The excellent photocatalytic performance can be attributed to the enhanced photo-absorption and narrow energy gap, abundant oxygen vacancies, high exposed {001} facets, smaller size and large specific surface area, and efficient electron-hole separation. The present work sheds light on the synergistic effect of PVP coating and in-situ formed oxygen vacancies on enhancing photocatalytic activity of Bi-based materials.

Interface modulation of AgBiO3 via BiOCl in situ growth: Simultaneously boosting O* and OVs production

Photocatalytic activity of the composite photocatalyst AgBiO3/BiOCl was examined after the interface of AgBiO3 was modified by growing BiOCl in situ and building heterojunction towards increasing reactive oxygen species (O*) and oxygen vacancy (OVs) production. The degradation of rhodamine B (RhB) revealed that the photocatalytic performance of the heterojunction structure of AgBiO3/BiOCl-x (x=0.05, 0.2, 2, 5) was significantly improved over that of AgBiO3 monomer, with the degradation effect of AgBiO3/BiOCl-2 reaching 99.6 % within 60 minutes and no significant decrease in performance after reuse (93 % degradation after four cycles). Similar experiments also used another contaminant, tetracycline hydrochloride (TC-HCl). Within 60 minutes, under visible light irradiation, the degradation rate of TC was 89.1 % and the degradation rate was 0.0367 min−1. The effects of catalyst addition, varied starting concentrations, and pH on RhB degradation were also studied. Furthermore, the free radical scavenging studies and chemical characterizations revealed that the principal reactive radicals functioning in the reaction system were h+, 1O2 and ‧O2-. Based on the findings, a potential catalytic mechanism for the synergistic degradation of RhB via photo-driven and chemical oxidation of AgBiO3/BiOCl heterostructures was postulated.

Enhanced oxidase mimic activity of raspberry-like N-doped Mn3O4 with oxygen vacancies for efficient colorimetric detection of gallic acid coupled with smartphone

The content of gallic acid (GA) is positively correlated with the quality grade of tea. Here, we developed a colorimetric method based on raspberry-like N-doped Mn3O4 nanospheres (N-Mn3O4 NSs) with oxidase-like activity for GA assay. Modulating the electronic structure of Mn3O4 by N doping could promote the catalysis ability, and the produced oxygen vacancies (OVs) can provide high surface energy and abundant active sites. The N-Mn3O4 NSs presented low Michaelis-Menten constant (Km) of 0.142 mM and maximum initial velocity (Vmax) of 9.8 × 10−6 M s−1. The sensor exhibited excellent analytical performance towards GA detection, including low LOD (0.028 μM) and promising linear range (5 ∼ 30 μM). It is attributed that OVs and O2− participated in TMB oxidation. Based on the reaction color changes, a visualized semi-quantitative GA detection could be realized via a smartphone-based system. It could be applied for evaluating GA quality in market-purchased black tea and green tea.

Nickel-tungsten co-doped biochar catalyst boosting ethylene glycol production from cellulose hydrogenolysis

Promoted ethylene glycol (EG) yield from cellulose hydrogenolysis is achieved via using Nickel-tungsten doped carbon catalysts prepared from glucose (x%Ni-y%WOx-GCT). Synchronously metal loading and carbon formation endow the catalyst excellent catalytic performance and high stability. Mechanistic investigations of the effects of metal loading and BrØnsted acid on EG yield are conducted. Increasing W loading promotes the content of polymerized WOx and consequently increases the amount of polytungstate species, thus lead to an improved BrØnsted acid content. Results reveal that promotion of B/L acid facilitates cellulose hydrolysis and suppresses isomerization of glucose to fructose. Besides, high W loading is beneficial for reduction of WOx to form W5+, producing oxygen vacancies to promote retro aldol condensation (RAC) of glucose to form acetaldehyde alcohol (an important intermediate for EG). By adopting the optimized 9%Ni-12%WOx-GC700 catalyst, a 100% cellulose conversion with a high EG yield of 65% is obtained due to the synergistic interactions between BrØnsted acid, W5+ and Ni0+ active sites.

Silicon-induced optimization on phase structure and surface property of Pd/ZrO2 catalysts for enhanced methane combustion

Palladium-based catalysts are relatively active for eliminating anthropogenic methane emissions through catalytic combustion, while they tend to degrade under drastic conditions. Herein, the silicon promoter was rationally introduced into Pd/ZrO2 catalysts to tune the monoclinic (m-) and tetragonal (t-) phase ratio and boost the catalytic performance. The introduced Si–O–Zr structure in ZrO2 not only reduced the grain size, but also produced oxygen vacancies due to lattice distortion, which greatly improved the stability of t-ZrO2 in high-temperature (800 °C) calcined catalysts. However, the excessive Si-addition caused the blockage of oxygen vacancies by amorphous SiO2, facilitating the transformation from t-ZrO2 to m-ZrO2. In the Pd/0.05Si–ZrO2 catalyst with a relatively high t-ZrO2 ratio, the presence of abundant oxygen vacancies stimulated the formation of surface-active oxygen and Pd2+ species, improved the reducibility of PdO and the redox of Pd ↔ PdO, meanwhile depressed the accumulation of hydroxyls. These, coupled with the enhanced hydrophobicity by Si-modification, made Pd/0.05Si–ZrO2 exhibit superior catalytic activity, stability and water-resistance to catalysts with low t-ZrO2 ratio. The revealed Si-promotion effect could be generalized to design phase-regulated Pd-based catalysts with optimized surface property for catalytic oxidation reactions.

Cobalt-doped tungsten suboxides for supercapacitor applications

A crucial hurdle in developing supercapacitors is the creation of metal oxides with nanoscale structures that possess improved chemically active surfaces, ion/charge transport kinetics, and minimized ion-diffusion pathways. A metal-doping strategy to produce oxygen vacancies and increase electrical conductivity has proven effective for designing high-performance materials for energy storage devices. Herein, cobalt-doped tungsten suboxide (Co-doped W18O49) is grown on carbon cloth (CC) using a solvothermal approach and used as an electrode material for supercapacitor applications for the first time. Through this strategy, structurally distorted W18O49 is obtained by detecting a more apparent amorphous area caused by forming more oxygen vacancies with the bending of the lattice fringes. Benefiting from the synergy of more oxygen vacancies, increased lattice spacing, a high specific surface area, and accelerated ion diffusion, the Co-doped W18O49/CC electrode achieves a specific capacity of 475 C g−1 (792 F g−1) at a current density of 1.0 A g−1, which is superior to that of the undoped W18O49/CC (259 C g−1, 432 F g−1) and among the highest reported to date. Interestingly, the asymmetric supercapacitor device assembled using Co-doped W18O49/CC//AC/CC can provide a high energy density of 35.0 Wh kg−1. This strategy proves that the distortion of the W18O49 structure by Co doping improves the ion storage performance and self-discharge behavior. Also, it can enhance the energy storage performance of other electrode materials.

Integrated Photochromic‐Photothermal Processes for Catalytic Plastic Upcycling

AbstractIncorporating high‐energy ultraviolet (UV) photons into photothermal catalytic processes may enable photothermal‐photochemical synergistic catalysis, which represents a transformative technology for waste plastic recycling. The major challenge is avoiding side reactions and by‐products caused by these energetic photons. Here, we break through the limitation of the existing photothermal conversion mechanism and propose a photochromic‐photothermal catalytic system based on polyol‐ligated TiO2 nanocrystals. Upon UV or sunlight irradiation, the chemically bonded polyols can rapidly capture holes generated by TiO2, enabling photogenerated electrons to reduce Ti4+ to Ti3+ and produce oxygen vacancies. The resulting abundant defect energy levels boost sunlight‐to‐heat conversion efficiency, and simultaneously the oxygen vacancies facilitate polyester glycolysis by activating the nucleophilic addition‐elimination process. As a result, compared to commercial TiO2 (P25), we achieve 6‐fold and 12.2‐fold performance enhancements under thermal and photothermal conditions, respectively, while maintaining high selectivity to high‐valued monomers. This paradigm‐shift strategy directs energetic UV photons for activating catalysts and avoids their interaction with reactants, opening the possibility of substantially elevating the efficiency of more solar‐driven catalysis.

Integrated Photochromic-Photothermal Processes for Catalytic Plastic Upcycling.

Incorporating high-energy ultraviolet (UV) photons into photothermal catalytic processes may enable photothermal-photochemical synergistic catalysis, which represents a transformative technology for waste plastic recycling. The major challenge is avoiding side reactions and by-products caused by these energetic photons. Here, we break through the limitation of the existing photothermal conversion mechanism and propose a photochromic-photothermal catalytic system based on polyol-ligated TiO2 nanocrystals. Upon UV or sunlight irradiation, the chemically bonded polyols can rapidly capture holes generated by TiO2 , enabling photogenerated electrons to reduce Ti4+ to Ti3+ and produce oxygen vacancies. The resulting abundant defect energy levels boost sunlight-to-heat conversion efficiency, and simultaneously the oxygen vacancies facilitate polyester glycolysis by activating the nucleophilic addition-elimination process. As a result, compared to commercial TiO2 (P25), we achieve 6-fold and 12.2-fold performance enhancements under thermal and photothermal conditions, respectively, while maintaining high selectivity to high-valued monomers. This paradigm-shift strategy directs energetic UV photons for activating catalysts and avoids their interaction with reactants, opening the possibility of substantially elevating the efficiency of more solar-driven catalysis.

Catalytic pyrolysis of corncob with Ni/CaO dual functional catalysts for hydrogen-rich gas

BackgroundAs "carbon neutrality" has become an important topic in the world, biomass has become one of the important clean energy sources. Ni/CaO dual functional catalysts (DFCs) are promising for catalytic utilization of biomass. MethodsIn this paper, we optimized the reaction conditions and secondary metals (Cu (ⅠB), Ce (ⅢB), Mo (ⅥB)) based on Ni/CaO DFCs to improve the performance of catalytic H2 production from corncob. Significant findingsThe addition of Ce and Mo improved the H2 production of Ni/CaO DFCs, while Cu played an inhibitory role. Compared with Ce and Mo, Cu inhibited the strong adsorption of CO2 and H2O, leading to a decrease in H2 production. Under pyrolysis conditions, Mo had a stronger cracking ability towards oxygenated tars, achieving the highest total gas yield. Under steam gasification conditions, Ce produced oxygen vacancies and reactive oxygen species through redox reactions (Ce4+↔Ce3+), which promoted H2O dissociation adsorption and water-gas shift reaction (WGS). Therefore, under steam gasification conditions, Ce-Ni/CaO DFCs achieved the optimal H2 production (33.72 mmol/gbiomass, 81.25%) with good cycling performance. The work provided a new idea for the development of Ni/CaO DFCs and H2 production from biomass.

CeFe-supported gold active catalyst applied to NO-SCR by CO: Effect of the gold deposition method and pretreatment

We demonstrate the effect of two preparation methods of gold catalysts (<1 wt%) –colloidal method, Au(CM), and deposition-precipitation, Au(DP)– and three pretreatments on the activity of Ce0.8Fe0.2O2-supported catalysts in the NO-SCR by CO. Au(CM) (Tlight-off = 256 °C) displays activity inferior to the support (Tlight-off = 186 °C) after all pretreatments, attributed to surface composition and stable‑carbonate formation. Au(DP) pretreated with O2 at 200 °C (Tlight-off = 82 °C) displays activity higher than the support. Auδ+-OH sites were evidenced by XPS and DRIFTS on Au(DP), key to converting CO to CO2 at lower temperatures, in turn, producing oxygen vacancies, responsible for reducing NO to N2.

Effect of Pr/Zr atomic ratio on the activity of catalytic oxidation denitration of PrxZr1−xO2−δ

AbstractThe PrxZr1–xO2–δ catalyst with different atom ratio of Pr/Zr was prepared by the sol-gel to catalytic oxidation denitration. Results showed that the efficiency of catalytic oxidation denitration increased initially and decreased afterward with the ratio of Pr atom increased. And the optimum denitration activity could achieve 94.62% at 250 °C when the atom ratio of Pr/Zr was 5:5. The catalysts were characterized by SEM, N2 adsorption-desorption, XRD, XPS, H2-TPR, and FT-IR. The results illustrated that the catalyst (Pr0.5Zr0.5O2–δ) with the best activity has a “layered” morphology, many pores on the surface, and it has a large specific surface area and pore volume of 77.74 m2/g and 0.66 cm3/g, respectively. Furthermore, the crystalline phase transforms from c-ZrO2 to Pr2Zr2O7 with the increasing of Pr atom. XPS and H2-TPR results showed that the surface chemosorption oxygen and surface Pr4+ oxides increased, and the rising of Pr atom ratio was beneficial to produce oxygen vacancy (Vӧ) site which advantageous to improve the efficiency of catalytic oxidation denitration. FT-IR characterization results indicated that Pr0.5Zr0.5O2–δ solid solution had better NO selectivity, which was conducive to the catalytic oxidation of NO. The anti-SO2 and H2O toxicity experiments showed that Pr/Zr atomic ratio at 5:5 had better anti-toxicity than other ratios. In addition, using IC to analysis absorption products, the result showed that NO2– and NO3– were the main products in the absorption solution.

Promotion effects of Pr-doped CeO2·H2O to Pt catalysts toward alcohol electrooxidation reaction

Considering that the co-catalyst which are rich in oxygen vacancy and hydroxyl functional groups have an obvious role in improving the activity and durability of Pt-based electrocatalyst, a novel Pr-doped CeO2·H2O cocatalyst (PrxCey(OH)a) has been prepared through a facile one-step hydrothermal method. The substitution of Pr3+ cation for host Ce4+ cation produces oxygen vacancies due to charge compensation effects. Pt/C-Pr1Ce6(OH)a exhibits an outstanding electrochemical oxidation performance with high peak current density of 2587 mA mg−1, 4116 mA mg−1, 2158 mA mg−1 in methanol, ethylene glycol, and glycerol oxidation reaction, respectively. PrxCey(OH)a provides significant co-catalysis effects by comparing with the alcohol electrooxidation performance of Pt/C, which shows a feasible strategy for the rational design of direct alcohol fuel cells catalysts.

Preparation of (La + Nb)-co-doped TiO2 and its polyvinylidene difluoride composites with high dielectric constants

Abstract Numerous studies have shown that ceramic materials with high dielectric constants and low dielectric losses can be obtained using donor–acceptor-doped TiO2. In this study, (La + Nb)-co-doped TiO2 [(La0.5Nb0.5) x Ti1−x O2 x-LNTO] ceramic powders were prepared using the sol–gel method. XRD demonstrates that LNTO is a rutile phase, and the lattice parameters change after doping, while X-ray photoelectron spectroscopy explains the doping mechanism, with doping of TiO2 producing oxygen vacancies and Ti3+, which form defective dipoles with the dopant ions to increase the dielectric constant of the material. The dielectric properties were investigated by physically co-blending x-LNTO/polyvinylidene difluoride (PVDF) composites. Compared with the TiO2/PVDF composite, the dielectric properties of the x-LNTO/PVDF composite were more excellent. The dielectric constant of 5-LNTO/PVDF reached 36.96, which was higher than that of the TiO2/PVDF composite (19.49) at a filler addition of 60 wt% and a frequency of 1 kHz.

The Role of Sulfur in the S‐PtRe/Al2O3 Catalysts: The Endogenous Deposition Effect on the Metal/acid Micro‐environment

AbstractAlumina is widely used as support in the industrial catalytic process. As a common impurity, the sulfur species, which are often considered a harmful component, play a positive role in some petrochemical reactions. Herein, the S‐modified catalysts were fabricated using the exogenous/endogenous deposition method to study the effect of the sulfur induced by introduction approaches. Series characterizations reveal that the exogenous sulfur from the sulfidation treatment affects the active metals by poisoning the low‐coordinated sites, leading to the active metal sites decrease. As for the endogenous deposition method, besides the poison effect, the removal of the endogenous sulfur from the S‐contain alumina support can produce oxygen vacancies, which can not only act as acid sites but work as an electron acceptor that optimizes the catalyst electronic structure. Benefits from the effect of endogenous sulfur, the catalyst with a suitable catalytic metal/acid micro‐environment exhibit the best dehydrocyclization performance.

Role of defects and interfacial interactions in ion irradiated noble metal based TiO2 hybrid nanostructures for improved photocatalytic investigation

Photocatalysis is an interesting process that can help solve problems like pollution and the growing energy crisis. Defect-induced one-dimensional titanium dioxide (TiO2) based hybrid nanostructures have attracted considerable interest for photocatalytic applications owing to chemical stability and environmental friendliness. The present study investigates the effect of defects and interface interactions induced by the high energy of 80 MeV Oxygen ion irradiation in Ag and Au, noble metal-based TiO2 nanorods (TiNRs) hybrid nanostructures. These irradiations at high fluences incorporated more defects in the system leading to damage to the nanostructures. It is found that the hybrids irradiated with the low fluence of 5E11 ions/cm2 are more prone to defects in comparison to hybrids irradiated with high fluence 5E12 ions/cm2 where the system gets annealed. The Micro-Raman studies reveal that this irradiation with high fluences damages the nanostructure of TiNRs. The morphological changes as well as defects induced in the hybrids are further studied for photocatalysis. The altered morphology of AuTiNRs hybrids with low fluences results in increased photocatalytic activity when compared to AgTiNRs hybrids with low fluences. Ion irradiation produces oxygen vacancies and the interface interactions that make it easier for charge carriers in these materials to be transported.

Investigation of the annealing treatment on the performance of TiO2 photoanode

Developing low-cost semiconductor photoanode toward efficient and stable oxygen evolution reaction (OER) is highly desirable for photoelectrochemical (PEC) water splitting. Herein, nanoparticulate titanium dioxide (TiO2) electrodes were prepared using Degussa P25 powders by spin-coating method. The effects of annealing conditions on the PEC performance of the nanoparticulate TiO2 photoanode was systematically investigated including temperature, annealing time and atmosphere. The results demonstrate that the TiO2/fluorine-doped tin oxide substrates (FTO/TiO2) electrode annealed at argon (Ar) atmosphere under 450 °C shows the highest PEC performance. The photocurrent density of FTO/TiO2 annealed in Ar for only 0.5 h reached to 120 μA/cm2 at 0.3 V vs. Hg/HgO which is about 10 times higher than that of the unannealed one. The X-ray photoelectron spectroscopy (XPS) results show the thermal treatment can produce oxygen vacancies on the surface of TiO2 which reduce the recombination of photogenerated electron-hole pairs and expanding the visible light absorption by introducing defective energy levels. The electrochemical impedance spectroscopy (EIS) approves that appropriate annealing treatment can effectively enhance the electron conductivity resulting in low charge transfer resistance. All these factors contribute to improving the PEC activity of TiO2 photoanode.

Structurally designable Bi2S3/P-doped ZnO S-scheme photothermal metamaterial enhanced CO2 reduction

In this study, a novel 3D Bi2S3/P-ZnO S-scheme gyroid metamaterial was prepared by 3D printing and the hydrothermal method. The unique gyroid macrostructure and nanoarray microstructure offer a large volume of active sites for the photothermal catalytic reaction, thus improving the overall utilization rate of light. ZnO obtained by sintering the precursor produces oxygen vacancies, primarily due to P doping. This enables it to have a photothermal effect. After loading Bi2S3, the photothermal effect of P-ZnO and Bi2S3 is coupled, further increasing the surface temperature of composite structure and speeding up the reaction rate. P-ZnO and Bi2S3 formed a S-scheme heterojunction, promoting the separation and transfer of photogenerated carriers. Under simulated sunlight, the CO and CH4 yield of Bi2S3/P-ZnO S-scheme gyroid metamaterials are 8.87 and 1.49 μmol h−1. These are 3.45 times and 4.65 times of P-ZnO gyroid structure, respectively. Through SEM, TEM, XPS, ESR and in-situ FTIR characterizations, the transfer paths of photogenerated carriers between heterojunctions were revealed, and the reaction paths of photothermal catalytic CO2 reduction were explored. The co-design of 3D structure and material allows for a novel concept for further improving photothermal catalytic performance.

Broad spectrum driven Y doped BiO2−x for enhanced degradation of tetracycline: Synergy between singlet oxygen and free radicals

The synergy of singlet oxygen and free radicals is crucial to driving organic pollutant degradation in water contain complex natural organic matter. In this study, the rare earth element yttrium doped bismuth oxide (Y-BiO2−x) photocatalyst was prepared by a hydrothermal method. Y doped BiO2−x enables produce oxygen vacancies and possess up-conversion property. The superoxide radicals (O2−), singlet oxygen (1O2), hydroxyl radicals (OH) and hole (h+) play a crucial role in photocatalytic reaction process. The increased 1O2 and hydrogen peroxide are mainly originated from O2−. The degradation efficiency of tetracycline (TC) reached 70.45 % and 40.17 % under Vis and NIR light, respectively. Notably, the TC removal efficiency of Y-BiO2−x maintained 65.92 % in the actual wastewater containing various anions and humic acid (HA), which originate from synergy of singlet oxygen and free radicals. This study provides a new strategy for synergistic singlet oxygen and free radicals to degradation of organic pollutants in complex water matrix.

Mechanistic insight into the charge carrier separation and molecular oxygen activation of manganese doping BiOBr hollow microspheres

High-efficiency separation of photogenerated charges and molecular oxygen activation is very important for photocatalytic removal of organic pollutants. However, the current understanding of the effect mechanism of metal substitution for the separation of photo-generated charges and molecular oxygen activation is still poor. Herein, efficient manganese (Mn)-doped BiOBr hollow microspheres synthesis, systematic characterizations, and theoretical calculation discovered that Mn-doping could not only induce produce oxygen vacancies (OVs), but also can act as active sites for catalytic reactions. The induced production of OVs and Mn2+/Mn3+ by Mn optimal doping introduced into BiOBr can synergistic promote the separation of photogenerated charges and molecular oxygen activation leads to significantly enhances degradation of crystal violet (CV). Upon analysis, Mn-doping introducing unsaturated d-orbital with bridging O2– formation π-donation accelerated the separation of photo-generated charges. Meanwhile, the larger overlap of Mn-3d orbitals with O2-2p orbitals forms a π-donation bond with charge transfer from metal to O2 leading to the oxygen–oxygen (OO) bond length and molecular oxygen activation. Finally, we proposed a possible mechanism to explain the highly efficient photocatalytic degradation performance of the acquired photocatalysts. This study provides not only a novel strategy for the rational design of highly active photocatalysts, but also in-depth insights into the separation of photo-generated charges and molecular oxygen activation.