Biohybrid Urchin-Like ZnO-Based Microspheres with Tunable Hierarchical Structures and Enhanced Photoelectrocatalytic Properties.

Microorganisms have attracted much attention to act as biotemplates for fabricating micro/nanostructured functional particles. However, it is still challenging to produce tunable hierarchical particles based on microorganisms with intricate architectures and superior stability. Herein, a novel strategy is developed to fabricate biohybrid urchin-like magnetic ZnO microspheres based on Chlorella (Ch.) with tunable hierarchical core-shell structures. Using Ch. cells as microspherical templates, Fe3 O4 nanoparticles and ZnO nanorod (NR) arrays are deposited in sequence to form the final biohybrid heterostructure microspheres (Ch.@Fe3 O4 @ZnO NRs). Ordered growth and structural regulation of 3D ZnO NR arrays are achieved via a facile and controllable manner. Compared with the prepared microspheres with diverse structure configurations of ZnO shells, the Ch.@Fe3 O4 @ZnO NRs possess excellent light absorption and photoelectrocatalysis performance toward tetracycline degradation (normalized apparent rate constant, k = 366.3 h-1 g-1 ), which is significantly larger than that of ZnO nanoflower/nanoparticle loaded types. It also proves that the synergistic enhancement of well-oriented ZnO NR arrays, heterojunction structures, and biomass features is the fundamental reason for outstanding photoelectrocatalytic activity. Due to the remarkable stability and versatility, this work provides abundant opportunities to construct biohybrid multilevel micro/nanostructures with significant potentials for practical applications.

Photoelectrocatalytic [4+2] Annulation for S-Heterocycle Assembly Enabled by Proton-Coupled Electron Transfer (PCET).

Cross-dehydrogenative couplings (CDC) present an efficient strategy for the assembly of biorelevant heterocycles, but are thus far largely limited to toxic transition metals and rather harsh reaction conditions. In sharp contrast, we, herein report on a mild photoelectrocatalyzed CDC-[4+2] annulation enabling the synthesis of functionalized isothiochromenes enabled by a proton-coupled electron transfer (PCET) strategy. The transformative photoelectrocatalysis obviated toxic transition-metal, high reaction temperatures, and stoichiometric chemical redox reagents. This approach was characterized by exceedingly mild conditions, ample substrate scope, and a commercially available catalyst. Gram-scale reactions and a telescoped synthesis route reflected the unique potential in the green synthesis of important S-heterocycles.

Unveiling Hierarchical Dendritic Co3O4-SnO2 Heterostructure for Efficient Water Purification.

The construction of a desirable, environmentally friendly, and cost-effective nanoheterostructure photoanode to treat refractory organics is critical and challenging. Herein, we unveiled a hierarchical dendritic Co3O4-SnO2 heterostructure via a sequential hydrothermal process. The time of the secondary hydrothermal process can control the size of the ultrathin SnO2 nanosheets on the basis of the Ostwald solidification mass conservation principle. Ti/Co3O4-SnO2-168h with critical growth size demonstrated a photoelectrocatalysis degradation rate of ∼93.3% for a high dye concentrate of 90 mg/L with acceptable long-term cyclability and durability over reported Co3O4-based electrodes because of the large electrochemically active area, low charge transfer resistance, and high photocurrent intensity. To gain insight into the photoelectric synergy, we proposed a type-II heterojunction between Co3O4 and SnO2, which prevents photogenerated carriers' recombination and improves the generation of dominant active species •O2-, 1O2, and h+. This work uncovered the Ti/Co3O4-SnO2-168 as a promising catalyst and provided a simple and inexpensive assembly strategy to obtain binary integrated nanohybrids with targeted functionalities.

Developing Z-scheme Bi2MoO6@α-MnO2 beaded core-shell heterostructure in photoelectrocatalytic treatment of organic wastewater.

Photoelectrocatalysis (PEC) oxidation technology with the combination of electrocatalysis and photocatalysis is an ideal candidate for treatment of dyeing wastewater containing multifarious intractable organic compounds with high chroma. Constructing high-quality heterojunction photoelectrodes can effectively suppress the recombination of photo-generated carriers, thereby achieving efficient removal of pollution. Herein, a beaded Bi2MoO6@α-MnO2 core-shell architecture with tunable hetero-interface was prepared by simple hydrothermal-solvothermal process. The as-synthesized Bi2MoO6@α-MnO2 had larger electrochemically active surface area, smaller charge transfer resistance and negative flat band potential, and higher separation efficiency of e-/h+ pairs than pure α-MnO2 or Bi2MoO6. It is noteworthy that the as-synthesized Bi2MoO6@α-MnO2 showed Z-scheme heterostructure as demonstrated by the free radical quenching experiments. The optimized Bi2MoO6@α-MnO2-2.5 exhibited the highest degradation rate of 88.64% in 120 min for reactive brilliant blue (KN-R) and accelerated stability with long-term(∼10000s) at the current density of 50 mA cm-2 in 1.0 mol L-1 H2SO4 solution. This study provides valuable insights into the straightforward preparation of heterogeneous electrodes, offering a promising approach for the treatment of wastewater in various industrial applications.

Progress in Promising Semiconductor Materials for Efficient Photoelectrocatalytic Hydrogen Production.

Photoelectrocatalytic (PEC) water decomposition provides a promising method for converting solar energy into green hydrogen energy. Indeed, significant advances and improvements have been made in various fundamental aspects for cutting-edge applications, such as water splitting and hydrogen production. However, the fairly low PEC efficiency of water decomposition by a semiconductor photoelectrode and photocorrosion seriously restrict the practical application of photoelectrochemistry. In this review, the mechanisms of PEC water decomposition are first introduced to provide a solid understanding of the PEC process and ensure that this review is accessible to a wide range of readers. Afterwards, notable achievements to date are outlined, and unique approaches involving promising semiconductor materials for efficient PEC hydrogen production, including metal oxide, sulfide, and graphite-phase carbon nitride, are described. Finally, four strategies which can effectively improve the hydrogen production rate-morphological control, doping, heterojunction, and surface modification-are discussed.

Static Organic p-n Junctions in Photoelectrodes for Solar Ammonia Production with 86% Internal Quantum Efficiency.

For photoelectrocatalytic cells, a limitation exists in finding appropriate photoelectrode configurations that couple efficient extraction of high-energy electrons from absorbed photons and selective catalysis. Here we report an organic p-n junction approach to fabricate molecular photoelectrodes for conversion of solar energy and nitrate into valuable ammonia product. Solar irradiation of the photoelectrode generates charge-separated states with electrons and holes spatially separated at the n-type and p-type components, as revealed by surface photovoltage mapping, at a quantum yield of 90%. The high-flux photogenerated electrons are rapidly transferred to the catalyst for solar ammonia production from nitrate reduction at an external quantum efficiency (EQE) and an internal quantum efficiency (IQE) of 57% and 86%, respectively. Time-resolved spectroscopic studies reveal that the large IQE originates from the combined high efficiencies for photoelectron generation, catalyst activation and dark catalysis. In a flow-cell setup coupled with a silicon solar cell, the photoelectrode without bias generates photocurrent of 57 mA cm-2 and ammonia at an EQE of 52%.

Proton-Coupled Electron Transfer in Photoelectrochemical Alcohol Oxidation Enhanced by Nickel-based Cocatalysts.

Using biomass oxidation reactions instead of water oxidation reactions is optimal for accomplishing biomass conversion and effective hydrogen generation. Here, we report that Fe2O3 photoanodes with a NiOOH cocatalyst exhibit excellent performance for photoelectrochemical oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA). The conversion efficiency for HMF reaches 98.5%, while the selectivity for FDCA is 94.2%. We revealed that HMF is oxidized through a spontaneous proton-coupled electron transfer (PCET) process with the high-valent phase of the Ni-based catalyst. The dangling oxygen and bridging oxygen of the high-valent phase species serve as proton-accepting sites. Furthermore, we pointed out that the deprotonated bond dissociation free energy difference between the catalysts and alcohols is the thermodynamic trigger for the PCET process. This study provides a reasonable explanation for the alcohol oxidation reaction, which is beneficial for designing biomass conversion systems.

Efficient Water Reforming of Biomass to H2 via Well-Organized Redox-Neutral Cleavage of C-C, O-H and C-H Bonds.

Hydrogen (H2) is a clean and environmentally friendly energy carrier. The depletion of fossil fuels makes renewable H2 production highly desirable. Water reforming of renewable biomass to hydrogen, with a relay of natural photosynthesis to biomass, would be an indirect pathway to realize the ideal but extremely challenging photocatalytic overall water splitting to hydrogen, with favorable thermodynamics. Since the seminal work of water reforming of biomass in 1980, great endeavors have been made. Nevertheless, hitherto, the entire kinetic pathway has been elusive, which seriously limits the reforming processes. Using a designed well-organized redox-neutral cleavage of C-C, O-H and C-H bonds enabled by photoelectrocatalysis, here, we show the efficient water reforming of biomass to hydrogen at room temperature, with a yield up to 93%. The clear insights into the kinetic pathway with oxidation of carbon radicals to carbon cations as the indicated rate-determining step, would cast brightness for efficient and sustainable hydrogen production to accelerate the hydrogen economy.

Converting CO2 into Value-Added Products by Cu2 O-Based Catalysts: From Photocatalysis, Electrocatalysis to Photoelectrocatalysis.

Converting CO2 into value-added products by photocatalysis, electrocatalysis, and photoelectrocatalysis is a promising method to alleviate the global environmental problems and energy crisis. Among the semiconductor materials applied in CO2 catalytic reduction, Cu2 O has the advantages of abundant reserves, low price and environmental friendliness. Moreover, Cu2 O has unique adsorption and activation properties for CO2 , which is conducive to the generation of C2+ products through CC coupling. This review introduces the basic principles of CO2 reduction and summarizes the pathways for the generation of C1 , C2 , and C2+ products. The factors affecting CO2 reduction performance are further discussed from the perspective of the reaction environment, medium, and novel reactor design. Then, the properties of Cu2 O-based catalysts in CO2 reduction are summarized and several optimization strategies to enhance their stability and redox capacity are discussed. Subsequently, the application of Cu2 O-based catalysts in photocatalytic, electrocatalytic, and photoelectrocatalytic CO2 reduction is described. Finally, the opportunities, challenges and several research directions of Cu2 O-based catalysts in the field of CO2 catalytic reduction are presented, which is guidance for its wide application in the energy and environmental fields is provided.

Thin Zinc Oxide Layer Passivating Bismuth Vanadate for Selective Photoelectrochemical Water Oxidation to Hydrogen Peroxide.

Selective photoelectrochemical (PEC) water oxidation to hydrogen peroxide is an underexplored option as opposed to the mainstream oxygen reduction reaction. Albeit interesting, selective H2 O2 production via oxidative pathway is plagued by the noncontrollable two-electron transfer reaction and the overoxidation of the thus-formed H2 O2 to O2 . Here, ZnO passivator-coated BiVO4 photoanode is reported for selective PEC H2 O2 production. Both the H2 O2 selectivity and production rate increase in the range of 1.0-2.0 V versus RHE under simulated sunlight irradiation. The photoelectrochemical impedance spectra and open-circuit potentials suggest a flattened band bending and positively shifted quasi-Fermi level of BiVO4 upon ZnO coating, facilitating H2 O2 generation and suppressing the competitive reaction of O2 evolution. The ZnO overlayer also inhibits H2 O2 decomposition, accelerates charge extraction from BiVO4 , and serves as a hole reservoir under photoexcitation. This work offers insights into surface states and the role of the coating layer in manipulating two/four-electron transfer for selective H2 O2 synthesis from PEC water oxidation.

Arenes and Heteroarenes C-H Functionalization Under Enabling Conditions: Electrochemistry, Photoelectrochemistry & Flow Technology.

C-H bond functionalization generates molecular complexity in single-step transformation. However, the activation of C-H bonds requires expensive metals or stoichiometric amounts of oxidizing/reducing species. In many cases, they often require pre-functionalization of starting molecules. Such pre-activating measures cause waste generation and their separation from the final product is also troublesome. In such a scenario, reactions activating elements generating from renewable energy resources such as electricity and light would be more efficient, green, and cost-effective. Further, incorporation of growing flow technology in chemical transformation processes will accelerate the safer accesses of valuable products. Arenes & heteroarenes are ubiquitous in pharmaceuticals, natural products, medicinal compounds, and other biologically important molecules. Herein, we discussed enabling tools and technologies used for the recent C-H bonds functionalization of arenes and heteroarenes.

Polygonal gold nanocrystal induced efficient phase transition in 2D-MoS2for enhancing photo-electrocatalytic hydrogen generation.

Plasmonic nanocrystals (NCs) assisted phase transition of two-dimensional molybdenum disulfide (2D-MoS2) unlashes numerous opportunities in the fields of energy harvesting via electrocatalysis and photoelectrocatalysis by enhancing electronic conductivity, increasing catalytic active sites, lowering Gibbs free energy for hydrogen adsorption and desorption, etc. Here, we report the synthesis of faceted gold pentagonal bi-pyramidal (Au-PBP) nanocrystals (NC) for efficient plasmon-induced phase transition (from 2 H to 1 T phase) in chemical vapor deposited 2D-MoS2. The as-developed Au-PBP NC with the increased number of corners and edges showed an enhanced multi-modal plasmonic effect under light irradiations. The overpotential of hydrogen evolution reaction (HER) was reduced by 61 mV, whereas the Tafel slope decreased by 23.7 mV/dec on photoexcitation of the Au-PBP@MoS2hybrid catalyst. The enhanced performance can be attributed to the light-induced 2H to 1 T phase transition of 2D-MoS2, increased active sites, reduced Gibbs free energy, efficient charge separation, change in surface potential, and improved electrical conductivity of 2D-MoS2film. From density functional theory (DFT) calculations, we obtain a significant change in the electronic properties of 2D-MoS2(i.e. work function, surface chemical potential, and the density of states), which was primarily due to the plasmonic interactions and exchange-interactions between the Au-PBP nanocrystals and monolayer 2D-MoS2, thereby enhancing the phase transition and improving the surface properties. This work would lay out finding assorted routes to explore more complex nanocrystals-based multipolar plasmonic NC to escalate the HER activity of 2D-MoS2and other 2D transition metal dichalcogenides.

Synergetic Oxidation of the Hydroxyl Radical and Superoxide Anion Lowers the Benzoquinone Intermediate Conversion Barrier and Potentiates Effective Aromatic Pollutant Mineralization.

Regulation of the free radical types is crucial but challenging in the ubiquitous heterogeneous catalytic oxidation for chemosynthesis, biotherapy, and environmental remediation. Here, using aromatic pollutant (AP) removal as a prototype, we identify the massive accumulation of the benzoquinone (BQ) intermediate in the hydroxyl radical (•OH)-mediated AP degradation process. Theoretical prediction and experiments demonstrate that BQ is both a Lewis acid and base because of its unique molecular and electronic structure caused by the existence of symmetrical carbonyl groups; therefore, it is hard to be electrophilically added by oxidizing •OH as a result of the high reaction energy barrier (ΔG = 1.74 eV). Fortunately, the introduction of the superoxide anion (•O2-) significantly lowers the conversion barrier (ΔG = 0.91 eV) of BQ because •O2- can act as the electron donor and acceptor simultaneously, electrophilically and nucleophilically add to BQ synchronously, and break it down. Subsequently, the breakdown products can then be further oxidized by •OH until completely mineralized. Such synergistic oxidation based on •OH and •O2- timely eliminates BQ, potentiates AP mineralization, and inhibits electrode fouling caused by high-resistance polymeric BQ; more importantly, it effectively reduces toxicity, saves energy and costs, and decreases the environmental footprint, evidenced by the life cycle assessment.

Mesostructured lead dioxide grown on titania nanotubes for diclofenac water removal through electrocatalytic and photoelectrocatalytic processes.

Mesostructured PbO2/TiO2 materials were synthesized to perform electrocatalysis (as electrooxidation, EO) and photoelectrocatalysis for removing diclofenac (DCF), 15 ppm concentration in 0.1 M NaSO4 solutions, at different pH conditions (3.0, 6.0 and 9.0) by applying 30 mA cm-2. Titania nanotubes (TiO2NTs)-based materials were prepared to synthetize with a massive PbO2 deposit on this support to obtain TiO2NTs/PbO2 and a TiO2NTs:PbO2 material consisting in a dispersed PbO2 deposit on TiO2-NTs that allowed the formation of a heterostructured surface of combined composition (TiO2 and PbO2). Organics removal (DCF and byproducts) was monitored through UV-vis spectrophotometry and high-performance liquid chromatography (HPLC) during degradation tests. TiO2NTs/PbO2 electrode was tested in both processes, removing DCF at neutral and alkaline solution conditions in EO while an unimportant photoactivity was registered at this material. Conversely, TiO2NTs:PbO2 was used as electrocatalytic material in EO experiments, achieving more than 50% of DCF removal at pH 6.0 by applying 30 mA cm-2. Also, for first time, the synergic effect was investigated when it was exposed to UV irradiation in photoelectrocatalytic experiments, enhancing its efficacy (⁓more than 20%) to remove DCF from a solution with 15 ppm over performance removals achieved (56%) when EO was applied under similar conditions. Chemical Oxygen Demand (COD) analyses showed that significantly higher DCF degradation is reached under photoelectrocatalysis, since COD values decrease a 76% against a 42% decrease achieved with electrocatalysis. Scavenging experiments showed a significant participation on the pharmaceutical oxidation process through the generation of photoholes (h+), hydroxyl radicals and sulfate-based oxidants.

Novel photoelectrochemical 3D-system for water disinfection by deposition of modified carbon nitride on vitreous carbon foam.

Graphitic carbon nitride (GCN) is an optical semiconductor with excellent photoactivity under visible light irradiation. It has been widely applied for organic micropollutant removal from contaminated water, and less investigated for microorganisms' inactivation. The photocatalytic degradation mechanism using GCN is attributed to a series of reactions with reactive oxygen species and photogenerated holes that can be boosted by modifying its physical-chemical structure. This work reports a successful improvement of the overall photocatalytic and electrocatalytic activities of the pristine material by thermal and chemical modification by a copolymerisation synthesis method. The copolymerisation of dicyandiamide as a precursor with barbituric acid strongly reduced photoluminescence due to the enhanced charge separation thus improving the catalyst efficiency under visible light irradiation. The material with 1.6 wt% of barbituric acid showed the best photocatalytic performance and electrochemical properties. This photocatalyst was selected for immobilisation on a conductive carbon foam, which promotes a higher electrochemical active surface area and enhanced mass transfer. This three-dimensional metal-free electrode was employed for the photoelectrochemical inactivation of two different microorganisms, Escherichia coli, and Enterococcus faecalis, obtaining removals below the detection limit after 30 min in simulated faecal-contaminated waters. This photoelectrochemical reactor was also applied to treat polluted river and urban waste waters, and the faecal contamination indicators were vastly reduced to values below the detection limit in 60 min in both cases, showing the wide applicability of this innovative photoelectrode for different types of polluted aqueous matrices.

Covalent organic frameworks (COFs) core@shell nanohybrids: Novel nanomaterial support towards environmental sustainability applications.

Covalent organic frameworks (COFs) based on core@shell nanohybrids have recently received significant attention and have become one of the most promising strategies for improving the stability and catalytic activity of COFs. Compared with traditional core@shell, COF-based core@shell hybrids own remarkable advantages, including size-selective reactions, bifunctional catalysis, and integration of multiple functions. These properties could enhance the stability and recyclability, resistance to sintering, and maximize the electronic interaction between the core and the shell. The activity and selectivity of COF-based core@shell could be simultaneously improved by taking benefit of the existing synergy between the functional encapsulating shell and the covered core material. Considering that, we have highlighted various topological diagrams and the role of COFs in COF-based core@shell hybrid for activity and selectivity enhancement. This concept article provides all-inclusive advances in the design and catalytic applications of COF-based core@shell hybrids. Various synthetic techniques have been developed for the facile tailoring of functional core@shell hybrids, including novel seed growth, in-situ, layer-by-layer, and one-pot method. Importantly, charge dynamics and structure-performance relationships are investigated through different characterization techniques. Different COF-based core@shell hybrids with established synergistic interactions have been detailed, and their influence on stability and catalytic efficiency for various applications is explained and discussed in this contribution. A comprehensive discussion on the remaining challenges associated with COF-based core@shell nanoparticles and research directions has also been provided to deliver insightful ideas for additional future developments.

Highly efficient binary copper-iron catalyst for photoelectrochemical carbon dioxide reduction toward methane.

A rational design of an electrocatalyst presents a promising avenue for solar fuels synthesis from carbon dioxide (CO2) fixation but is extremely challenging. Herein, we use density functional theory calculations to study an inexpensive binary copper-iron catalyst for photoelectrochemical CO2 reduction toward methane. The calculations of reaction energetics suggest that Cu and Fe in the binary system can work in synergy to significantly deform the linear configuration of CO2 and reduce the high energy barrier by stabilizing the reaction intermediates, thus spontaneously favoring CO2 activation and conversion for methane synthesis. Experimentally, the designed CuFe catalyst exhibits a high current density of -38.3 mA⋅cm-2 using industry-ready silicon photoelectrodes with an impressive methane Faradaic efficiency of up to 51%, leading to a distinct turnover frequency of 2,176 h-1 under air mass 1.5 global (AM 1.5G) one-sun illumination.

Application of Electrochemical Oxidation for Water and Wastewater Treatment: An Overview.

In recent years, the discharge of various emerging pollutants, chemicals, and dyes in water and wastewater has represented one of the prominent human problems. Since water pollution is directly related to human health, highly resistant and emerging compounds in aquatic environments will pose many potential risks to the health of all living beings. Therefore, water pollution is a very acute problem that has constantly increased in recent years with the expansion of various industries. Consequently, choosing efficient and innovative wastewater treatment methods to remove contaminants is crucial. Among advanced oxidation processes, electrochemical oxidation (EO) is the most common and effective method for removing persistent pollutants from municipal and industrial wastewater. However, despite the great progress in using EO to treat real wastewater, there are still many gaps. This is due to the lack of comprehensive information on the operating parameters which affect the process and its operating costs. In this paper, among various scientific articles, the impact of operational parameters on the EO performances, a comparison between different electrochemical reactor configurations, and a report on general mechanisms of electrochemical oxidation of organic pollutants have been reported. Moreover, an evaluation of cost analysis and energy consumption requirements have also been discussed. Finally, the combination process between EO and photocatalysis (PC), called photoelectrocatalysis (PEC), has been discussed and reviewed briefly. This article shows that there is a direct relationship between important operating parameters with the amount of costs and the final removal efficiency of emerging pollutants. Optimal operating conditions can be achieved by paying special attention to reactor design, which can lead to higher efficiency and more efficient treatment. The rapid development of EO for removing emerging pollutants from impacted water and its combination with other green methods can result in more efficient approaches to face the pressing water pollution challenge. PEC proved to be a promising pollutants degradation technology, in which renewable energy sources can be adopted as a primer to perform an environmentally friendly water treatment.

Molten Salts-Driven Discovery of a Polar Mixed-Anion 3D Framework at the Nanoscale: Zn4 Si2 O7 Cl2 , Charge Transport and Photoelectrocatalytic Water Splitting.

Mixed-anion compounds widen the chemical space of attainable materials compared to single anionic compounds, but the exploration of their structural diversity is limited by common synthetic paths. Especially, oxychlorides rely mainly on layered structures, which suffer from low stability during photo(electro)catalytic processes. Herein we report a strategy to design a new polar 3D tetrahedral framework with composition Zn4 Si2 O7 Cl2 . We use a molten salt medium to enable low temperature crystallization of nanowires of this new compound, by relying on tetrahedral building units present in the melt to build the connectivity of the oxychloride. These units are combined with silicon-based connectors from a non-oxidic Zintl phase to enable precise tuning of the oxygen content. This structure brings high chemical and thermal stability, as well as strongly anisotropic hole mobility along the polar axis. These features, associated with the ability to adjust the transport properties by doping, enable to tune water splitting properties for photoelectrocatalytic H2 evolution and water oxidation. This work then paves the way to a new family of mixed-anion solids.

Photo/Electrocatalytic Hydrogen Peroxide Production by Manganese and Iron Porphyrin/Molybdenum Disulfide Nanoensembles.

The oxygen reduction reaction (ORR) 2e- pathway provides an alternative and green route for industrial hydrogen peroxide (H2 O2 ) production. Herein, the ORR photo/electrocatalytic activity in the alkaline electrolyte of manganese and iron porphyrin (MnP and FeP, respectively) electrostatically associated with modified 1T/2H MoS2 nanosheets is reported. The best performing catalyst, MnP/MoS2 , exhibits excellent electrocatalytic performance towards selective H2 O2 formation, with a low overpotential of 20 mV for the 2e- ORR pathway (Eons  = 680 mV vs RHE) and an H2 O2 yield up to 99%. Upon visible light irradiation, MnP/MoS2 catalyst shows significant activity enhancement along with good stability. Electrochemical impedance spectroscopy assays suggest a reduced charge transfer resistance value at the interface with the electrolyte, indicating an efficient intra-ensemble transfer process of the photo-excited electrons through the formation of a type II heterojunction or Schottky contact, and therefore justifies the boosted electrochemical activities in the presence of light. Overall, this work is expected to inspire the design of novel advanced photo/electrocatalysts, paving the way for sustainable industrial H2 O2 production.