Electrosynthesis Of Hydrogen Peroxide Research Articles

Hydrogen Peroxide Electrosynthesis via Selective Oxygen Reduction Reactions Through Interfacial Reaction Microenvironment Engineering.

The electrochemical two-electron oxygen reduction reaction (2e- ORR) offers a compelling alternative for decentralized and on-site H2O2 production compared to the conventional anthraquinone process. To advance this electrosynthesis system, there is growing interest in optimizing the interfacial reaction microenvironment to boost electrocatalytic performance. This review consolidates recent advancements in reaction microenvironment engineering for the selective electrocatalytic conversion of O2 to H2O2. Starting with fundamental insights into interfacial electrocatalytic mechanisms, an overview of various strategies for constructing the favorable local reaction environment, including adjusting electrode wettability, enhancing mesoscale mass transfer, elevating local pH, incorporating electrolyte additives, and employing pulsed electrocatalysis techniques is provided. Alongside these regulation strategies, the corresponding analyses and technical remarks are also presented. Finally, a summary and outlook on critical challenges, suggesting future research directions to inspire microenvironment engineering and accelerate the practical application of H2O2 electrosynthesis is delivered.

Epoxidized Single-Atom Co-N-C Catalysts Promote the Oxygen Reduction Reaction via a Two-Electron Pathway.

Coordination structure and group modifications of single-atom catalysts are essential for regulating superficial electronic structures and reaction activities. Epoxy group-modified single-atom Co-N-C configuration demonstrates exceptional catalytic performance for hydrogen peroxide production. Through the manipulation of the coordination structure of Co-N-C and the doped epoxy groups, we elucidate the origin of catalytic activity in epoxygroup-modified Co-N-C configurations. Theoretical results indicate that the second coordination sphere of the Co-N-C structure is essential for the regulation of the two-electron pathway by the epoxy groups acting as cocatalysts. This cocatalytic mechanism originates from hydrogen bonding interactions between the epoxy groups and the OOH intermediates. Three epoxy groups within the second coordination sphere of Co-N-C configuration lead to the achievement of the optimal G*OOH (∼4.22 eV) for hydrogen peroxide production. This study offers novel insights into the design of catalytic materials for the electrosynthesis of hydrogen peroxide as well as the engineering of their surface structures.

Ionic liquid modifying conductivity and hydrophobicity of B4C for enhanced electrosynthesis of H2O2

Electrosynthesis of hydrogen peroxide (H2O2) via two-electron oxygen reduction reaction (2e− ORR) is an attractive energy-efficient and decentralized alternative to the conventional anthraquinone process. However, designing non-precious metal catalysts with high activity, selectivity and stability is a great challenge. Here, we report a facile and effective approach to improve the catalytic performance of commercial boron carbide (B4C) by loading ionic liquid (IL), which exploits the complementary properties of high electrical conductivity and hydrophobicity of IL. The B4C catalyst with optimal IL loading possesses the highest conductivity and O2 adsorption, exhibiting high H2O2 selectivity in both neutral (∼96 %) and alkaline (∼93 %) electrolyte, which are nearly ∼34 % and ∼19 % higher than pristine B4C, respectively. Moreover, its production rate is ∼1.5 times that of pristine B4C at 130 mA cm−2 current density, resulting in a high concentration of H2O2 (5.93 wt%) produced in flow-cell reactor. The long-term cycle test demonstrates the desirable stability of IL@B4C/GDE, which is attributed to the high hydrophobicity and tight bonding between IL@B4C and the substrate, giving a strong flood-proof capability at the three-phase interface and avoiding rapid flooding by the electrolyte. This work provides new insights into designing non-precious metal electrocatalysts for efficient electrosynthesis of H2O2, emphasizing the role of IL in interface engineering.

Nature‐Inspired N, O Co‐Coordinated Manganese Single‐Atom Catalyst for Efficient Hydrogen Peroxide Electrosynthesis

AbstractThe two‐electron oxygen reduction reaction (2e− ORR) is a pivotal pathway for the distributed production of hydrogen peroxide (H2O2). In nature, enzymes containing manganese (Mn) centers can convert reactive oxygen species into H2O2. However, Mn‐based heterogeneous catalysts for 2e− ORR are scarcely reported. Herein, we developed a nature‐inspired single‐atom electrocatalyst comprising N, O co‐coordinated Mn sites, utilizing carbon dots as the modulation platform (Mn CD/C). As‐synthesized Mn CD/C exhibited exceptional 2e− ORR activity with an onset potential of 0.786 V and a maximum H2O2 selectivity of 95.8 %. Impressively, Mn CD/C continuously produced 0.1 M H2O2 solution at 200 mA/cm2 for 50 h in the flow cell, with negligible loss in activity and H2O2 faradaic efficiency, demonstrating practical application potential. The enhanced activity was attributed to the incorporation of Mn atomic sites into the carbon dots. Theoretical calculations revealed that the N, O co‐coordinated structure, combined with abundant oxygen‐containing functional groups on the carbon dots, optimized the binding strength of intermediate *OOH at the Mn sites to the apex of the catalytic activity volcano. This work illustrates that carbon dots can serve as a versatile platform for modulating the microenvironment of single‐atom catalysts and for the rational design of nature‐inspired catalysts.

Nature-Inspired N, O Co-Coordinated Manganese Single-Atom Catalyst for Efficient Hydrogen Peroxide Electrosynthesis.

The two-electron oxygen reduction reaction (2e- ORR) is a pivotal pathway for the distributed production of hydrogen peroxide (H2O2). In nature, enzymes containing manganese (Mn) centers can convert reactive oxygen species into H2O2. However, Mn-based heterogeneous catalysts for 2e- ORR are scarcely reported. Herein, we developed a nature-inspired single-atom electrocatalyst comprising N, O co-coordinated Mn sites, utilizing carbon dots as the modulation platform (Mn CD/C). As-synthesized Mn CD/C exhibited exceptional 2e- ORR activity with an onset potential of 0.786 V and a maximum H2O2 selectivity of 95.8 %. Impressively, Mn CD/C continuously produced 0.1 M H2O2 solution at 200 mA/cm2 for 50 h in the flow cell, with negligible loss in activity and H2O2 faradaic efficiency, demonstrating practical application potential. The enhanced activity was attributed to the incorporation of Mn atomic sites into the carbon dots. Theoretical calculations revealed that the N, O co-coordinated structure, combined with abundant oxygen-containing functional groups on the carbon dots, optimized the binding strength of intermediate *OOH at the Mn sites to the apex of the catalytic activity volcano. This work illustrates that carbon dots can serve as a versatile platform for modulating the microenvironment of single-atom catalysts and for the rational design of nature-inspired catalysts.

Accelerated Proton-Coupled Electron Transfer via Engineering Palladium Sub-Nanoclusters for Scalable Electrosynthesis of Hydrogen Peroxide.

Electrosynthesis of H2O2 from oxygen reduction reaction via a two-electron pathway is vital as an alternative for the energy-intensive anthraquinone process. However, this process is largely hindered in neutral and alkaline conditions due to sluggish kinetics associated with the transformation of intermediate O2* into OOH* via proton-coupled electron transfer sourced from slow water dissociation. Herein, we developed Pd sub-nanoclusters on the nickel ditelluride nanosheets (Pd SNCs/NiTe2) to enhance the performance of H2O2 electrosynthesis. The newly-developed Pd SNCs/NiTe2 exhibited a H2O2 selectivity of as high as 99 % and a positive shift of onset potential up to 0.81 V. Combined theoretical calculations and experimental studies (e.g., X-ray absorption and attenuated total reflectance-Fourier transform infrared spectra measurements) revealed that the Pd sub-nanoclusters supported by NiTe2 nanosheets efficiently reduced the energy barrier of water dissociation to generate more protons, facilitating the proton feeding kinetics. When used in a flow cell, Pd SNCs/NiTe2 cathode efficiently produced H2O2 with a maximum yield rate of 1.75 mmol h-1 cm-2 and a current efficiency of 95 % at 100 mA cm-2. Further, an accumulated H2O2 concentration of 1.43 mol L-1 was reached after 10 hours of continuous electrolysis, showing the potential for practical H2O2 electrosynthesis.

Accelerated Proton‐Coupled Electron Transfer via Engineering Palladium Sub‐Nanoclusters for Scalable Electrosynthesis of Hydrogen Peroxide

AbstractElectrosynthesis of H2O2 from oxygen reduction reaction via a two‐electron pathway is vital as an alternative for the energy‐intensive anthraquinone process. However, this process is largely hindered in neutral and alkaline conditions due to sluggish kinetics associated with the transformation of intermediate O2* into OOH* via proton‐coupled electron transfer sourced from slow water dissociation. Herein, we developed Pd sub‐nanoclusters on the nickel ditelluride nanosheets (Pd SNCs/NiTe2) to enhance the performance of H2O2 electrosynthesis. The newly‐developed Pd SNCs/NiTe2 exhibited a H2O2 selectivity of as high as 99 % and a positive shift of onset potential up to 0.81 V. Combined theoretical calculations and experimental studies (e.g., X‐ray absorption and attenuated total reflectance‐Fourier transform infrared spectra measurements) revealed that the Pd sub‐nanoclusters supported by NiTe2 nanosheets efficiently reduced the energy barrier of water dissociation to generate more protons, facilitating the proton feeding kinetics. When used in a flow cell, Pd SNCs/NiTe2 cathode efficiently produced H2O2 with a maximum yield rate of 1.75 mmol h−1 cm−2 and a current efficiency of 95 % at 100 mA cm−2. Further, an accumulated H2O2 concentration of 1.43 mol L−1 was reached after 10 hours of continuous electrolysis, showing the potential for practical H2O2 electrosynthesis.

Selective and durable H2O2 electrosynthesis catalyst in acid by selenization induced straining and phasing

Developing efficient electrocatalysts for acidic electrosynthesis of hydrogen peroxide (H2O2) holds considerable significance, while the selectivity and stability of most materials are compromised under acidic conditions. Herein, we demonstrate that constructing amorphous platinum–selenium (Pt–Se) shells on crystalline Pt cores can manipulate the oxygen reduction reaction (ORR) pathway to efficiently catalyze the electrosynthesis of H2O2 in acids. The Se2‒Pt nanoparticles, with optimized shell thickness, exhibit over 95% selectivity for H2O2 production, while suppressing its decomposition. In flow cell reactor, Se2‒Pt nanoparticles maintain current density of 250 mA cm−2 for 400 h, yielding a H2O2 concentration of 113.2 g L−1 with productivity of 4160.3 mmol gcat−1 h−1 for effective organic dye degradation. The constructed amorphous Pt–Se shell leads to desirable O2 adsorption mode for increased selectivity and induces strain for optimized OOH* binding, accelerating the reaction kinetics. This selenization approach is generalizable to other noble metals for tuning 2e‒ ORR pathway.

Highly efficient electrosynthesis of hydrogen peroxide through reversible transformation between catechol and o-benzoquinone on polydopamine modified carbon black

Carbon-based materials are more promising catalysts for H2O2 electrochemical production. However, the common method for modifying carbon-based materials is surface functionalization with harsh and uncontrollable reaction conditions, hindering the precise regulation of the active sites. Herein, we proposed a carbon-based material modified by polydopamine (CB-PDA) that was easily prepared and used in air diffusion electrode system for H2O2 production. The rapid and reversible transformation between catechol and o-benzoquinone on PDA could improve the H2O2 selectivity from 75.5 % to 97.0 % during the electrocatalytic process. The detection of adsorbed *HOOH and *OOH in oxygen reduction reaction proved the preference of CB-PDA for the two-electron pathway. The H2O2 formation rate constant of CB-PDA increased significantly from 25.85 to 60.82 mM h−1. The highest cumulative H2O2 concentration could reach 10200 mg L−1 in 9 h. Long-term operation tests proved the good operational stability. Furthermore, this system was cost-effective without additional aeration energy consumption and could achieve rapid disinfection in 10 min, which would have great potential to be used in environmental remediation.

Cost-efficient electrosynthesis of hydrogen peroxide in acidic and neutral solutions

Oxygen reduction reaction is considered a green and low-carbon approach for H2O2 production. Low space-time yield and high energy consumption are serious challenges to the implementation of a commercial scale now. A cost-efficient H2O2 electrosynthesis using a recycled gold catalyst is developed here. The carbon-supported gold catalyst is synthesized using electroplating gold wastewater, which indicates good catalysis performances for both sulfite oxidation and H2O2 production. The sulfite/air fuel cell adopting the bifunctional gold catalyst can directly produce 8.70±0.53 g L−1 H2O2 in 0.5 mol L−1 Na2SO4 solution, with a good current efficiency of 71.56 %±2.13 % and a remarkable space-time yield of 27.20±1.17 mg cm−2 h−1. Adopting the desulfurization solution from flue gas as the anodic sacrificial agent, the electricity costs for acidic and neutral H2O2 electrosynthesis are only 2.09–3.82 kWh kg−1. The reported H2O2 electrosynthesis performances, especially for power consumption, are also summarized and compared.

Boosting pH-universal electrosynthesis of hydrogen peroxide by regulating three-phase interface of carbon gas penetration electrode

Electrochemical oxygen reduction is a sustainable method for onsite H2O2 production. However, pH-universal H2O2 electrosynthesis still suffered from low kinetics and efficiency. Here carbon nanotube hollow fiber (CNT-HF) with porous fiber wall is designed to enhance H2O2 electrosynthesis via tailoring the three-phase interface. The CNT-HF gas penetration electrode with enhanced local electric field is favorable for boosting oxygen mass transfer and regulating catalyst-electrolyte interfacial protons, resulting in significantly enhanced H2O2 production performance in comparison with CNT planar gas diffusion electrode under pH-universal media. Its H2O2 production efficiency is 98.1% at pH 13. Meanwhile, H2O2 production efficiency of 96.1% and high H2O2 concentration of 46.4 g L-1 are achieved at pH 1 with 20 mM K+. Experimental and simulation results reveal the boosted H2O2 electrosynthesis on CNT-HF is mainly contributed from its significantly reduced diffusion layer thickness, enhanced local electric field and interfacial proton regulation by K+ enriched at electrode surface.

Progress of Metal Chalcogenides as Catalysts for Efficient Electrosynthesis of Hydrogen Peroxide.

Hydrogen peroxide (H2O2) is a high-demand chemical, valued as a powerful and eco-friendly oxidant for various industrial applications. The traditional industrial method for producing H2O2, known as the anthraquinone process, is both costly and environmentally problematic. Electrochemical synthesis, which produces H2O2 using electricity, offers a sustainable alternative, particularly suited for small-scale, continuous on-site H2O2 generation due to the portability of electrocatalytic devices. For efficient H2O2 electrosynthesis, electrocatalysts must exhibit high selectivity, activity, and stability for the two-electron pathway-oxygen reduction reaction (2e- ORR). Transition-metal chalcogenide (TMC)-based materials have emerged as promising candidates for effective 2e- ORR due to their high activity in acidic environments and the abundance of their constituent elements. This review examines the potential of TMC-based catalysts in H2O2 electrosynthesis, categorizing them into noble-metal and non-noble-metal chalcogenides. It underscores the importance of achieving high selectivity, activity, and stability in 2e- ORR. By reviewing recent advancements and identifying key challenges, this review provides valuable insights into the development of TMC-based electrocatalysts for sustainable H2O2 production.

Enhanced electron transfer kinetics via constructing co-catalytic system of cerium oxide and carbon dots enabling efficient electrosynthesis of hydrogen peroxide in neutral media

The sluggish kinetics coupled with the competition of four-electron pathway in neutral media diminishes the production efficiency of hydrogen peroxide (H2O2) via the two-electron oxygen reduction reaction (2e− ORR). To address this dilemma, this contribution proposes one electron modulation strategy to expedite the charge transfer capability by integrating carbon dots with CeO2 (CDs/CeO2) for the efficient neutral electrosynthesis of H2O2. It was found that the integration could effectively bolster both the activity and selectivity of 2e− ORR on CDs and CeO2. Remarkably, the highest 2e− selectivity could reach up to 92 % for the optimized CDs/CeO2, substantially surpassing that (77 %) of pristine CeO2, together with about 1.5 times enhancement of activity. Meanwhile, it also delivered a superior long durability at 20 mA cm−2 for 24 h and a high Faraday efficiency of 97 %. Further in-situ transient potential scanning (TPS) technique revealed that the pseudo-capacitance and charge storage capacity of CeO2 were significantly tuned by CDs during dynamic ORR process, being conducive to the reaction kinetics and the 2e− selectivity. The findings in this work not only extends the co-catalytic system based on CDs and rare earth materials for 2e− ORR, but also offers novel insights into correlation between their electron distribution dynamics and 2e− ORR performance.

Defective PTFE with Dense Active Sites Enabling Rapid H2O2 Production for Efficient Water Purification

AbstractThe electrosynthesis of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (2e−‐ORR) enables high energy utilization and distributed H2O2 production. Rational catalyst design is essential for achieving efficient H2O2 production, in which fluorine‐modified carbon materials hold great potential. However, conventional methods can only induce limited loading of fluorine atoms in carbon‐based catalysts, leading to unsatisfying electrochemical performance. Herein, the design of fluorine‐containing active sites with high density and high 2e−‐ORR selectivity is achieved by loading fluorine‐containing chained polytetrafluoroethylene precursors onto conductive carbon substrates by plasma‐assisted ball milling technique. Consequently, the defect‐rich PTFE@CNTs show a high selectivity of over 95% and a high H2O2 yield of more than 35 mol g−1 h−1. Furthermore, the electrochemical production of H2O2 can be readily integrated with water purification units to decompose contaminants, showing over 80% degradation of multiple dyes within 1 h and over 95% removal ratio of antibiotics within 4 h. In addition, 100% sterilization of staphylococcus aureus is achieved by on‐site accumulating H2O2 in commercial saline for only 30 min. This defect engineering strategy through plasma ball milling provides a promising and universal avenue toward designing highly active and efficient electrocatalysts for 2e−‐ORR as well as other electrochemical processes.

Nitrogen-doped vertical graphene for highly efficient hydrogen peroxide electrosynthesis in acidic environment

Electrochemical oxygen reduction (ORR) through a two-electron (2e−) pathway offers a green route for on-demand production of hydrogen peroxide (H2O2), which is an industrially valuable chemical as well as a renewable energy carrier. Metal-free carbon-based materials have been exploited as promising catalysts for H2O2 generation; however, they often exhibit poor performance with low productivity under acidic conditions. Herein, a nitrogen-doped vertical graphene catalyst is developed with a stable hydrophobic solid–liquid-gas three-phase interface (TPI) enabled by polydimethylsiloxane (PDMS) coating. The catalyst exhibits a high Faradaic efficiency (FE) of ∼ 80 % across a wide potential range from 0 to −0.6 V vs. reversible hydrogen electrode (RHE) at a maximum current density of 140 mA cm−2, resulting in a remarkably high H2O2 productivity of 21 mol gcatalyst−1h−1 in acid. Furthermore, a high concentration of H2O2 up to 10,500 ppm is obtained with the FE maintained at ∼ 75 %. Confocal laser scanning microscopy (CLSM) and fluorescence lifetime analysis reveal that the hydrophobic TPI increases gas diffusion and local pH value to enhance both activity and selectivity towards H2O2. This work provides valuable insights into the rational design of metal-free carbon-based catalysts for efficient H2O2 generation.

Boosting acidic hydrogen peroxide electrosynthesis on 2D metal-organic framework nanosheets based on cobalt porphyrins

The 2-electron electrocatalytic oxygen reduction reaction (2e− ORR) to hydrogen peroxide (H2O2) represents a promising strategy to resolve the high energy consumption and increasing environmental concerns inherent in the traditional anthraquinone process. The acidic 2e− ORR has emerged as an exciting alternative for industrial-level H2O2 production, whereas is hampered by the inferior H2O2 selectivity due to the uncontrollable proton-coupled electron transfer processes in an acidic environment. Herein, an ultrathin 2D metal–organic frameworks (MOFs) nanosheet based on cobalt tetra(4-carboxyphenyl) porphine (Co-TCPP NSs) is designed to promote H2O2 selectivity up to 96.5 %, accompanied with a remarkable H2O2 generation rate of 4677.42 mg·L−1·h−1. Of note, the Co-TCPP NSs also demonstrate its potential for the electro-Fenton process with a cumulative H2O2 concentration of 1.21 wt%, highlighting its practical potential in portable H2O2 generation electrochemical devices for distributed applications. Our findings demonstrated that the efficient H2O2 electrosynthesis could be attributed to the attenuated *OOH adsorption over Co-N4 moiety on the Co-TCPP NSs, which consequently suppresses its further reduction to form H2O. This work highlights the potential of 2D MOF architecture for the 2e− ORR and provides an atomic-level insight into the enhanced H2O2 selectivity.

Fe-O4 Motif Activated Graphitic Carbon via Oxo-Bridge for Highly Selective H2O2 Electrosynthesis.

Carbon-based materials have been utilized as effective catalysts for hydrogen peroxide electrosynthesis via two-electron oxygen reduction reaction (2e ORR), however the insufficient selectivity and productivity still hindered the further industrial applications. In this work, we report the Fe-O4 motif activated graphitic carbon material which enabled highly selective H2O2 electrosynthesis operating at high current density with excellent anti-poisoning property. In the bulk production test, the concentration of H2O2 cumulated to 8.6 % in 24 h and the corresponding production rate of 33.5 mol gcat -1 h-1 outperformed all previously reported materials. Theoretical model backed by in situ characterization verified α-C surrounding the Fe-O4 motif as the actual reaction site in terms of thermodynamics and kinetics aspects. The strategy of activating carbon reaction site by metal center via oxo-bridge provides inspiring insights for the rational design of carbon materials for heterogeneous catalysis.

Fe−O4 Motif Activated Graphitic Carbon via Oxo‐Bridge for Highly Selective H2O2 Electrosynthesis

AbstractCarbon‐based materials have been utilized as effective catalysts for hydrogen peroxide electrosynthesis via two‐electron oxygen reduction reaction (2e ORR), however the insufficient selectivity and productivity still hindered the further industrial applications. In this work, we report the Fe−O4 motif activated graphitic carbon material which enabled highly selective H2O2 electrosynthesis operating at high current density with excellent anti‐poisoning property. In the bulk production test, the concentration of H2O2 cumulated to 8.6 % in 24 h and the corresponding production rate of 33.5 mol gcat−1 h−1 outperformed all previously reported materials. Theoretical model backed by in situ characterization verified α‐C surrounding the Fe−O4 motif as the actual reaction site in terms of thermodynamics and kinetics aspects. The strategy of activating carbon reaction site by metal center via oxo‐bridge provides inspiring insights for the rational design of carbon materials for heterogeneous catalysis.

Insight into the deterioration mechanism of gas diffusion electrode during long-term electrosynthesis of hydrogen peroxide under industrially relevant current densities

The long-term stability of gas diffusion electrodes (GDEs) is critical for industrial H2O2 electrosynthesis from two-electron oxygen reduction reaction (2e-ORR), but has rarely been investigated. Herein, we evaluated the stability of carbon black-polytetrafluoroethylene (CB-PTFE) based GDEs during H2O2 electrosynthesis in sodium sulfate (Na2SO4) electrolytes under industrially relevant conditions. Results show that the GDEs maintained stable H2O2 production with Faradaic efficiencies (FEs) of ∼75 % for ∼300 h under 150 mA/cm2. However, FEs then declined gradually to eventually ∼15 % at 840 h, after which the GDE failed due to water flooding. Increasing applied current density to 200 mA/cm2 accelerated the deterioration process and caused electrode failure after 350 h operation. Characterizations of the GDEs used for varying durations indicate that the deterioration of GDEs is mainly caused by oxidation of CB catalysts, defluorination of PTFE, and intercalation of Na in CB particles during H2O2 electrosynthesis. These three interrelating mechanisms gradually decreased the hydrophobicity, the 2e-ORR activity and selectivity of GDEs, and increased the porosity of GDEs. These changes in turn promoted H2O2 decomposition and progressive water intrusion into the internal pores of GDEs during H2O2 electrosynthesis, thus causing the gradual decreases of FEs and electrode flooding. Due to the gradual changes of GDE properties, it is challenging to maintain long-term stable H2O2 production under industrially relevant current densities. More studies are needed to improve the design and operation of GDEs to resolve the deterioration process of GDEs and thus extend their lifetime during H2O2 electrosynthesis.

Metal Atom-Support Interaction in Single Atom Catalysts toward Hydrogen Peroxide Electrosynthesis.

Single metal atom catalysts (SACs) have garnered considerable attention as promising agents for catalyzing important industrial reactions, particularly the electrochemical synthesis of hydrogen peroxide (H2O2) through the two-electron oxygen reduction reaction (ORR). Within this field, the metal atom-support interaction (MASI) assumes a decisive role, profoundly influencing the catalytic activity and selectivity exhibited by SACs, and triggers a decade-long surge dedicated to unraveling the modulation of MASI as a means to enhance the catalytic performance of SACs. In this comprehensive review, we present a systematic summary and categorization of recent advancements pertaining to MASI modulation for achieving efficient electrochemical H2O2 synthesis. We start by introducing the fundamental concept of the MASI, followed by a detailed and comprehensive analysis of the correlation between the MASI and catalytic performance. We describe how this knowledge can be harnessed to design SACs with optimized MASI to increase the efficiency of H2O2 electrosynthesis. Finally, we distill the challenges that lay ahead in this field and provide a forward-looking perspective on the future research directions that can be pursued.