Rate Of H2O2 Production Research Articles

Enhancing the crystallinity of covalent organic frameworks to achieve improved photocatalytic hydrogen peroxide production under ambient conditions

Photocatalytic production of hydrogen peroxide (H2O2) presents a promising strategy for environmental remediation and energy production. However, achieving clean and efficient H2O2 production under ambient conditions without organic sacrificial agents remains challenging. Enhancing the low crystallinity of covalent organic frameworks (COFs) can promote the separation and transmission of photo-generated carriers, thereby boosting their photocatalytic performance. Herein, we introduce a novel synthetic approach by substituting traditional acetic acid catalysts with organic base catalysts to enhance the crystallinity of β-ketoenamine-linked COF, TpBD-COF. Compared to TpBD-COF-A synthesized using acetic acid catalysts, TpBD-COF-B, synthesized with organic base catalysts, exhibited advancements including increased absorption intensity in the visible spectrum, reduced photoluminescence intensity, enhanced photo-generated carrier separation performance, and a 2.1-fold increase in photocatalytic H2O2 production. Under visible light irradiation, TpBD-COF-B achieved a photocatalytic H2O2 production rate of 533 µmol h−1 g−1 using only air and water, without the need for organic sacrificial agents. Furthermore, TpBD-COF-B also exhibited good performance in long-term catalytic production experiments, tests with actual water bodies, and cyclic usage experiments. This study offers a strategy for enhancing the crystallinity of COFs to improve their photocatalytic activity, with promising applications in clean energy production and environmental remediation.

Pyridine‐Based Covalent Organic Frameworks with Pyridyl‐Imine Structures for Boosting Photocatalytic H2O2 Production via One‐Step 2e− Oxygen Reduction

AbstractBipyridine‐based covalent organic frameworks (COFs) have emerged as promising contenders for the photocatalytic generation of hydrogen peroxide (H2O2). However, the presence of imine nitrogen alters the mode of H2O2 generation from an efficient one‐step two‐electron (2e−) route to a two‐step 2e− oxygen reduction pathway. In this work, we introduce 3,3′‐bipyridine units into imine‐based COF skeletons, creating a pyridyl‐imine structure with two adjacent nitrogen atoms between the pyridine ring and imine linkage. This unique bipyridine‐like architecture can effectively suppress the two‐step 2e− ORR process at the single imine‐nitrogen site, facilitating a more efficient one‐step 2e− pathway. Consequently, the optimized pyridyl‐imine COF (PyIm‐COF) exhibits a remarkable H2O2 production rate of up to 5850 μmol h−1 g−1, nearly double that of pristine bipyridine COFs. This work provides valuable insight into the rational design of functionalized COFs for enhanced H2O2 production in photocatalysis.

Pyridine-Based Covalent Organic Frameworks with Pyridyl-Imine Structures for Boosting Photocatalytic H2O2 Production via One-Step 2e- Oxygen Reduction.

Bipyridine-based covalent organic frameworks (COFs) have emerged as promising contenders for the photocatalytic generation of hydrogen peroxide (H2O2). However, the presence of imine nitrogen alters the mode of H2O2 generation from an efficient one-step two-electron (2e-) route to a two-step 2e- oxygen reduction pathway. In this work, we introduce 3,3'-bipyridine units into imine-based COF skeletons, creating a pyridyl-imine structure with two adjacent nitrogen atoms between the pyridine ring and imine linkage. This unique bipyridine-like architecture can effectively suppress the two-step 2e- ORR process at the single imine-nitrogen site, facilitating a more efficient one-step 2e- pathway. Consequently, the optimized pyridyl-imine COF (PyIm-COF) exhibits a remarkable H2O2 production rate of up to 5850 μmol h-1 g-1, nearly double that of pristine bipyridine COFs. This work provides valuable insight into the rational design of functionalized COFs for enhanced H2O2 production in photocatalysis.

Efficient Electrosynthesis of Hydrogen Peroxide Using Oxygen-Doped Porous Carbon Catalysts at Industrial Current Densities.

Metal-free carbon catalysts (MFCCs) are one of the commonly used catalysts for electrocatalytic two-electron oxygen reduction (2e- ORR) synthesis of hydrogen peroxide (H2O2). Oxygen doping is an effective means to improve the performance of MFCCs, but the performance of oxygen-doped carbon catalysts is still not high enough, and the contribution of different oxygen functional groups (OFGs) to the catalytic performance is still inconclusive. In this paper, carbon-based catalysts with different oxygen contents and ratios of OFGs were prepared, and the high 2e- ORR activity of COOH + C-OH was demonstrated by combining the results of experiments and theoretical calculations. The prepared oxygen-doped carbon-based catalyst C-0.1M80 achieved an onset potential of 0.795 V (vs RHE), a selectivity of up to 98.2% (0.6 V vs RHE), and a H2O2 oxidation current of 1.33 mA cm-2 (0.5 V vs RHE) in a rotating ring-disk electrode test (0.1 M KOH solution), which was an outstanding performance in MFCCs. In a solid electrolyte flow cell, C-0.1M80 achieved a Faraday efficiency of 97.5% at 200 mA cm-2 with a corresponding H2O2 production rate of 123.7 mg cm-2 h-1. In addition, a flow cell stability test was performed at an industrial current density (100 mA cm-2) with an astounding 200 h of uninterrupted operation, also achieving an outstanding average Faradaic efficiency (95.8%).

Vinyl-Group-Anchored Covalent Organic Framework for Promoting the Photocatalytic Generation of Hydrogen Peroxide.

The artificial photosynthesis of H2O2 from water and oxygen using semiconductor photocatalysts is attracting increasing levels of attention owing to its green, environmentally friendly, and energy-saving characteristics. Although covalent organic frameworks (COFs) are promising materials for promoting photocatalytic H2O2 production owing to their structural and functional diversity, they typically suffer from low charge-generation and -transfer efficiencies as well as rapid charge recombination, which restricts their use as catalysts for photocatalytic H2O2 production. Herein, we report a strategy for anchoring vinyl moieties to a COF skeleton to facilitate charge separation and migration, thereby promoting photocatalytic H2O2 generation. This vinyl-group-bearing COF photocatalyst exhibits a H2O2-production rate of 84.5 μmol h-1 (per 10 mg), which is ten-times higher than that of the analog devoid of vinyl functionality and superior to most reported COF photocatalysts. Both experimental and theoretical studies provide deep insight into the origin of the improved photocatalytic performance. These findings are expected to facilitate the rational design and modification of organic semiconductors for use in photocatalytic applications.

Enhancing photocatalytic H2O2 production with Au co-catalysts through electronic structure modification

Gold-based co-catalysts are a promising class of materials with potential applications in photocatalytic H2O2 production. However, current approaches with Au co-catalysts show limited H2O2 production due to intrinsically weak O2 adsorption at the Au site. We report an approach to strengthen O2 adsorption at Au sites, and to improve H2O2 production, through the formation of electron-deficient Auδ+ sites by modifying the electronic structure. In this case, we report the synthesis of TiO2/MoSx-Au, following selective deposition of Au onto a MoSx surface which is then further anchored onto TiO2. We further show that the catalyst achieves a significantly increased H2O2 production rate of 30.44 mmol g−1 h−1 in O2-saturated solution containing ethanol. Density functional theory calculations and X-ray photoelectron spectroscopy analysis reveal that the MoSx mediator induces the formation of electron-deficient Auδ+ sites thereby decreasing the antibonding-orbital occupancy of Au-Oads and subsequently enhancing O2 adsorption. This strategy may be useful for rationally designing the electronic structure of catalyst surfaces to facilitate artificial photosynthesis.

Photocatalytic Hydrogen Peroxide Production through Functionalized Semiconductive Metal-Organic Frameworks.

Hydrogen peroxide (H2O2) holds significance as a vital chemical with the potential to serve as an energy carrier. Compared with the conventional anthraquinone process, photocatalytic H2O2 production has emerged as an appealing alternative because of its energy efficiency and environmental sustainability. However, the existing photocatalysts suffer from low catalytic efficiency, limited tunability of optical properties, and reliance on sacrificial agents due to high energy loss caused by inefficient charge separation. Therefore, developing catalysts with tunable optical properties and efficient charge separation is desirable. In this work, we introduce postsynthetic functionalization into an electrically conductive metal-organic framework, namely, DPT-MOF. Leveraging DPT (3,6-di(4-pyridyl)-1,2,4,5-tetrazine) as a pillar ligand, we exploited click-type chemistry to manipulate band position and charge separation efficiency, allowing for photocatalytic nonsacrificial H2O2 production. Notably, the fluorine-functionalized MOF exhibited the highest H2O2 production rate of 1676 μmol g-1 h-1 under visible light in O2-saturated water among our other samples. This high production rate is attributed to the tuned electronic structure and prolonged charge lifetime facilitated by the fluorine groups. This work highlights the effectiveness of postsynthetic methodology in tuning optical properties, opening a promising avenue for advancing the field of semiconductive MOF-based photocatalysis.

Enhanced Generation of Reactive Oxygen Species via Piezoelectrics based on p-n Heterojunctions with Built-In Electric Field.

Tuning the charge transfer processes through a built-in electric field is an effective way to accelerate the dynamics of electro- and photocatalytic reactions. However, the coupling of the built-in electric field of p-n heterojunctions and the microstrain-induced polarization on the impact of piezocatalysis has not been fully explored. Herein, we demonstrate the role of the built-in electric field of p-type BiOI/n-type BiVO4 heterojunctions in enhancing their piezocatalytic behaviors. The highly crystalline p-n heterojunction is synthesized by using a coprecipitation method under ambient aqueous conditions. Under ultrasonic irradiation in water exposed to air, the p-n heterojunctions exhibit significantly higher production rates of reactive species (·OH, ·O2-, and 1O2) as compared to isolated BiVO4 and BiOI. Also, the piezocatalytic rate of H2O2 production with the BiOI/BiVO4 heterojunction reaches 480 μmol g-1 h-1, which is 1.6- and 12-fold higher than those of BiVO4 and BiOI, respectively. Furthermore, the p-n heterojunction maintains a highly stable H2O2 production rate under ultrasonic irradiation for up to 5 h. The results from the experiments and equation-driven simulations of the strain and piezoelectric potential distributions indicate that the piezocatalytic reactivity of the p-n heterojunction resulted from the polarization intensity induced by periodic ultrasound, which is enhanced by the built-in electric field of the p-n heterojunctions. This study provides new insights into the design of piezocatalysts and opens up new prospects for applications in medicine, environmental remediation, and sonochemical sensors.

Robust Covalent Organic Framework Photocatalysts for H2O2 Production: Linkage Position Matters.

Covalent organic frameworks (COFs) are promising photocatalysts for hydrogen peroxide (H2O2) synthesis. However, the nature of organic polymers makes the balance between high activity and stability challenging. We demonstrate that the linkage position matters in the design of robust COF photocatalysts with durable high activity without sacrificial reagents. COFs with ortho- and para-linkages (o-COFs and p-COFs) were constructed by 1,3,5-triformylphloroglucinol with benzene-, pyridine-, pyrazine-orthodiamines and paradiamines. The pyrzaine-containing o-COFs with two pyridinic nitrogen atoms exhibited a H2O2 production rate of 4396 μmol g-1 h-1 together with long-time continuous H2O2 photosynthesis performance in pure water (48 h), superior to the corresponding p-COFs. A four-step reaction mechanism is proposed by density function calculations. Moreover, the active sites and origin of stability enhancement for o-COFs are clarified. This work provides a simple and effective molecular design strategy in the design of robust COF photocatalysts for artificial H2O2 photosynthesis.

AC-electrochemical synthesis of H2O2 by breathing O2 in three-phase interface

Conventional electrosynthesis of H2O2 through a two-electron oxygen reduction reaction (2e− ORR) requires continuous O2 feeding as the reactant, which is produced by oxygen evolution reaction (OER) in water electrolysis. In principle, H2O2 can be directly synthesized from water once the 2e− ORR is coupled with OER in one electrode. Unfortunately, such effective coupling has not yet been established. Herein, we created a cyclic oxygen exhalation-inhalation for on-demand and on-site H2O2 production by coupling the OER and 2e− ORR with a facile alternating-current (AC) electrocatalytic process. By ingeniously manipulating the reaction interfaces and operating voltage, we achieved efficient and stable in-situ H2O2 production. The rapid oxygen transfer in the localized three-phase interface favors the sufficient electrochemical reactions. The AC-electrocatalytic system exhibits highest performance including H2O2 production rate of 90.16 mmol h−1 gcat−1. Moreover, such AC-electrocatalysis inspires a new strategy to combine multiple electrocatalytic reactions into one electrode for fundamental study and practical applications.

Robust Covalent Organic Framework Photocatalysts for H2O2 Production: Linkage Position Matters

AbstractCovalent organic frameworks (COFs) are promising photocatalysts for hydrogen peroxide (H2O2) synthesis. However, the nature of organic polymers makes the balance between high activity and stability challenging. We demonstrate that the linkage position matters in the design of robust COF photocatalysts with durable high activity without sacrificial reagents. COFs with ortho‐ and para‐linkages (o‐COFs and p‐COFs) were constructed by 1,3,5‐triformylphloroglucinol with benzene‐, pyridine‐, pyrazine‐orthodiamines and paradiamines. The pyrzaine‐containing o‐COFs with two pyridinic nitrogen atoms exhibited a H2O2 production rate of 4396 μmol g−1 h−1 together with long‐time continuous H2O2 photosynthesis performance in pure water (48 h), superior to the corresponding p‐COFs. A four‐step reaction mechanism is proposed by density function calculations. Moreover, the active sites and origin of stability enhancement for o‐COFs are clarified. This work provides a simple and effective molecular design strategy in the design of robust COF photocatalysts for artificial H2O2 photosynthesis.

Pauling-type adsorption of O2 induced by S-scheme electric field for boosted photocatalytic H2O2 production

The effective adsorption of oxygen (O2) molecules over photocatalysts is a critical step in promoting the performance of photocatalytic H2O2 production. However, g-C3N4 usually features a Yeager-type (side-on) adsorption configuration of O2 molecules, which causes the breaking of O–O bonds and severely hinders the H2O2 production activity. Herein, we synthesized an oxygen-vacancy-rich TiO2–x/g-C3N4 step-scheme (S-scheme) heterojunction to regulate the oxygen adsorption configuration and improve the 2e– ORR selectivity of H2O2 production. In-situ X-ray photoelectron spectroscopy (in-situ XPS) and density functional theory (DFT) calculations reveal that the S-scheme heterojunction is formed between TiO2–x and g-C3N4. The difference between their Fermi levels leads to the electron flow from g-C3N4 to TiO2–x, which increases the electron-deficient sites in g-C3N4. As a result, the cleavage of O–O bonds on the surface of g-C3N4 is avoided and the oxygen adsorption configuration is tuned from Yeager-type to Pauling-type (end-on). Consequently, the photocatalytic H2O2 production rate is dramatically improved to 1780.3 μmol h–1, which is about 5 times higher than that of pristine g-C3N4. This work paves a new way to tailor the oxygen adsorption configuration by rationally designing S-scheme heterojunction photocatalysts.

Preparation of nitrogen-doped carbon pyrolyzed from ZIF-8 and its performance in electrocatalytic oxygen reduction to hydrogen peroxide

As an environment-friendly strategy, electrocatalytic hydrogen peroxide (H2O2) generation via two-electron oxygen reduction reaction (2e– ORR) has attracted significant scientific and technological attention. Nevertheless, limited to the low catalytic activity and high cost of noble metal-containing catalysts, forging desired electrocatalysts with high catalytic activity, low cost, and sustainability is still challenging. In this work, nitrogen doped porous carbon materials named p-ZIF-800 and p-ZIF-950 were obtained by pyrolysis of zeolitic imidazolate framework-8 (ZIF-8) nanocrystals at 800 °C and 950 °C, respectively. Then, they were employed as a catalytic layer in the gas diffusion electrodes p-ZIF-n/Ni/CB (n = 800 °C or 950 °C, CB = acetylene black). The production rates of H2O2 are up to 1.18 mg h−1 cm−2 and 1.25 mg h−1 cm−2 for p-ZIF-800/Ni/CB and p-ZIF-950/Ni/CB, respectively. Noticeably, although p-ZIF-800 had a lower degree of graphitization the difference in catalytic activity between p-ZIF-800 and p-ZIF-950 is negligible. This can be construed as a higher total nitrogen and richer mesoporous structure in p-ZIF-800 than in p-ZIF-950. Under optimized conditions of an electrode spacing of 3 cm, a pH value of 6.5, and a current density of 7.5 mA cm−2, the H2O2 production rate of p-ZIF-800/Ni/CB in the “floating-cathode” cell is up to as high as 2.09 mg h−1 cm−2, which is about 3.3 times higher than that of the cell with the “submerged-cathode” under aeration and stirring. Also, the p-ZIF-800/Ni/CB cathode demonstrates remarkable stability, it maintains its structure without losing catalytic activity after 5 catalytic cycle experiments. These results indicate that the state-of-the-art pyrolysis-based nitrogen-doped porous carbon materials exhibit a high potential for the advanced electrocatalyst of H2O2 electrogeneration.

Regulating Benzene Ring Number as Connector in Covalent Organic Framework for Boosting Photosynthesis of H2O2 from Seawater.

Photosynthesis of H2O2 from seawater represents a promising pathway to acquire H2O2, but it is still restricted by the lack of a highly active photocatalyst. In this work, we propose a convenient strategy of regulating the number of benzene rings to boost the catalytic activity of materials. This is demonstrated by ECUT-COF-31 with adding two benzene rings as the connector, which can result in 1.7-fold enhancement in the H2O2 production rate relative to ECUT-COF-30 with just one benzene ring as the connector. The reason for enhancement is mainly due to the release of *OOH from the surface of catalyst and the final formation of H2O2 being easier in ECUT-COF-31 than in ECUT-COF-30. Moreover, ECUT-COF-31 provides a stable photogeneration of H2O2 for 70 h, and a theoretically remarkable H2O2 production of 58.7 mmol per day from seawater using one gram of photocatalyst, while the cost of the used raw material is as low as 0.24 $/g.

Electronic Structure Modulation of Oxygen-Enriched Defective CdS for Efficient Photocatalytic H2O2 Production.

Artificial photosynthesis for hydrogen peroxide (H2O2) presents a sustainable and environmentally friendly approach to generate clean fuel and chemicals. However, the catalytic activity is hindered by challenges such as severe charge recombination, insufficient active sites, and poor selectivity. Here, a robust strategy is proposed to regulate the electronic structure of catalyst by the collaborative effect of defect engineering and dopant. The well designed oxygen-doped CdS nanorods with S2- defects and Cd2+ 4d10 electron configuration (CdS-O,Sv) is successfully synthesized, and the Cd2+ active sites around S defects or oxygen atoms exhibit rapid charge separation, suppressed carrier recombination, and enhanced charge utilization. Consequently, a remarkable H2O2 production rate of 1.62mmolg-1h-1 under air conditions is acquired, with an apparent quantum yield (AQY) of 9.96% at a single wavelength of 450nm. This work provides valuable insights into the synergistic effect between defect and doping on catalytic activity.

COF/In2S3 S-Scheme Photocatalyst with Enhanced Light Absorption and H2O2-Production Activity and fs-TA Investigation.

Photocatalytic hydrogen peroxide (H2O2) synthesis from water and O2 is an economical, eco-friendly, and sustainable route for H2O2 production. However, single-component photocatalysts are subjected to limited light-harvesting range, fast carrier recombination, and weak redox power. To promote photogenerated carrier separation and enhance redox abilities, an organic/inorganic S-scheme photocatalyst is fabricated by in situ growing In2S3 nanosheets on a covalent organic framwork (COF) substrate for efficient H2O2 production in pure water. Interestingly, compared to unitary COF and In2S3, the COF/In2S3 S-scheme photocatalysts exhibit significantly larger light-harvesting range and stronger visible-light absorption. Partial density of state calculation, X-ray photoelectron spectroscopy, and femtosecond transient absorption spectroscopy reveal that the coordination between In2S3 and COF induces the formation of mid-gap hybrid energy levels, leading to smaller energy gaps and broadened absorption. Combining electron spin resonance spectroscopy, radical-trapping experiments, and isotope labeling experiments, three pathways for H2O2 formation are identified. Benefited from expanded light-absorption range, enhanced carrier separation, strong redox power, and multichannel H2O2 formation, the optimal composite shows an impressive H2O2-production rate of 5713.2µmol g-1 h-1 in pure water. This work exemplifies an effective strategy to ameliorate COF-based photocatalysts by building S-scheme heterojunctions and provides molecular-level insights into their impact on energy level modulation.

Tailored Exfoliation of Polymeric Carbon Nitride for Photocatalytic H2O2 Production and CH4 Valorization Mediated by O2 Activation.

The exfoliation of bulk C3N4 (BCN) into ultrathin layered structure is an effective strategy to boost photocatalytic efficiency by exposing interior active sites and accelerating charge separation and transportation. Herein, we report a novel nitrate anion intercalation-decomposition (NID) strategy that is effective in peeling off BCN into few-layer C3N4 (fl-CN) with tailored thickness down to bi-layer. This strategy only involves hydrothermal treatment of BCN in diluted HNO3 aqueous solution, followed by pyrolysis at various temperatures. The decomposition of the nitrate anions not only exfoliates BCN and changes the band structure, but also incorporates oxygen species onto fl-CN, which is conducive to O2 adsorption and hence relevant chemical processes. In photocatalytic O2 reduction under visible light irradiation, the H2O2 production rate over the optimal fl-CN-530 catalyst is 952 μmol g-1 h-1, which is 8.8 times that over BCN. More importantly, under full arc irradiation and in the absence of hole scavenger, CH4 can be photocatalytically oxidized by on-site formed H2O2 and active oxygen species to generate value-added C1 oxygenates with high selectivity of 99.2 % and record-high production rate of 1893 μmol g-1 h-1 among the metal-free C3N4-based photocatalysts.

Tailored Exfoliation of Polymeric Carbon Nitride for Photocatalytic H2O2 Production and CH4 Valorization Mediated by O2 Activation

AbstractThe exfoliation of bulk C3N4 (BCN) into ultrathin layered structure is an effective strategy to boost photocatalytic efficiency by exposing interior active sites and accelerating charge separation and transportation. Herein, we report a novel nitrate anion intercalation‐decomposition (NID) strategy that is effective in peeling off BCN into few‐layer C3N4 (fl‐CN) with tailored thickness down to bi‐layer. This strategy only involves hydrothermal treatment of BCN in diluted HNO3 aqueous solution, followed by pyrolysis at various temperatures. The decomposition of the nitrate anions not only exfoliates BCN and changes the band structure, but also incorporates oxygen species onto fl‐CN, which is conducive to O2 adsorption and hence relevant chemical processes. In photocatalytic O2 reduction under visible light irradiation, the H2O2 production rate over the optimal fl‐CN‐530 catalyst is 952 μmol g−1 h−1, which is 8.8 times that over BCN. More importantly, under full arc irradiation and in the absence of hole scavenger, CH4 can be photocatalytically oxidized by on‐site formed H2O2 and active oxygen species to generate value‐added C1 oxygenates with high selectivity of 99.2 % and record‐high production rate of 1893 μmol g−1 h−1 among the metal‐free C3N4‐based photocatalysts.

Efficient H2O2 photocatalysis by a novel organic semiconductor with electron donor-acceptor interface

Nowadays, considerable attention has been directed towards the two-electron oxygen reduction for the photocatalytic H2O2 production. However, the challenge of insufficient charge separation capacity markedly constrains the rate of H2O2 production. Herein, we designed a donor-acceptor (D-A) interface characterized by rapid charge migration and separation to enhance the photocatalytic H2O2 production. Specifically, naphthalenetetracarboxylic acid-diaminotriazole as an organic molecule has been judiciously chosen as the electron donor, while perylenetetracarboxylic acid serves as the electron acceptor. The novel semiconductor with D-A interface performs markedly strong internal electric field and demonstrates an excellent H2O2 production rate of 3176 μM h−1. The pronounced internal electric field facilitated by the D-A interface effectively expedites charge separation and induces the migration of photogenerated carriers to the O2 reduction sites. This study introduces a novel paradigm for the design of D-A interfacial organic materials aimed at realizing enhanced photocatalytic capabilities.

Spaced Double Hydrogen Bonding in an Imidazole Poly Ionic Liquid Composite for Highly Efficient and Selective Photocatalytic Air Reductive H2O2 Synthesis

AbstractPhotocatalytic oxygen reductive H2O2 production is a promising approach to alternative industrial anthraquinone processes while suffering from the requirement of pure O2 feedstock for practical application. Herein, we report a spaced double hydrogen bond (IC−H‐bond) through multi‐component Radziszewski reaction in an imidazole poly‐ionic‐liquid composite (SI‐PIL‐TiO2) and levofloxacin hydrochloride (LEV) electron donor for highly efficient and selective photocatalytic air reductive H2O2 production. It is found that the IC−H‐bond formed by spaced imino (−NH−) group of SI‐PIL‐TiO2 and carbonyl (−C=O) group of LEV can switch the imidazole active sites characteristic from a covered state to a fully exposed one to shield the strong adsorption of electron donor and N2 in the air, and propel an intenser positive potential and more efficient orbitals binding patterns of SI‐PIL‐TiO2 surface to establish competitive active sites for selectivity O2 chemisorption. Moreover, the high electron enrichment of imidazole as an active site for the 2e− oxygen reduction ensures the rapid reduction of O2. Therefore, the IC−H‐bond enables a total O2 utilization and conversion efficiency of 94.8 % from direct photocatalytic air reduction, achieving a H2O2 production rate of 1518 μmol/g/h that is 16 and 23 times compared to poly‐ionic‐liquid composite without spaced imino groups (PIL‐TiO2) and TiO2, respectively.