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Artificial photosynthesis holds immense promise for sustainable clean energy harvesting, with recent strides in material engineering with the earth abundant elements enabling efficient utilization of the visible solar spectrum for photoelectrochemical catalytic water splitting. Here, we have investigated the impact of substitutional Cu doping at all three cation sites in Ba2YNbO6 (BYN) using density functional theory calculations at the Heyd-Scuseria-Ernzerhof-06 level. One of the key findings is that the defect formation energy follows the hierarchy Nb > Ba > Y. The presence of an oxygen vacancy (OV) enhances the co-solubility of Cu substitution of Nb, particularly when placed outside the CuO6 unit, while it has a contrary effect for Y substitution. Cu replacement reduces the bandgap as Nb > Y ≫ Ba vis-à-vis pure BYN, while extending it into the visible part of the solar spectrum for Nb and Y replacement cases, albeit with OV causing a slight blue shift to them, without reducing the oxidation state of Cu due to strong charge-delocalization. Cu doping at Y and Nb sites retains the direct band transition character of BYN, a feature removed by OV. While all the bare Cu doped systems exhibit formation of a weak electron polaron, the placement of OV tends to annihilate this except for the system comprising first nearest neighbor placement of an OV relative to the Cu substitution at an Nb site. Notably, Cu doping at the Nb site significantly enhances optical activity, particularly ∼2.0–2.5 eV, resulting in promising candidates for photoelectrochemical catalysts. [ABSTRACT FROM AUTHOR]

We present a highly efficient workflow for designing semiconductor structures with specific physical properties, which can be utilized for a range of applications, including photocatalytic water splitting. Our algorithm generates candidate structures composed of earth-abundant elements that exhibit optimal light-trapping, high efficiency in H 2 and/or O 2 production, and resistance to reduction and oxidation in aqueous media. To achieve this, we use an ionic translation model trained on the Inorganic Crystal Structure Database to predict over 30 000 undiscovered semiconductor compositions. These predictions are then screened for redox stability under hydrogen evolution reaction or oxygen evolution reaction conditions before generating thermodynamically stable crystal structures and calculating accurate bandgap values for the compounds. Our approach results in the identification of dozens of promising semiconductor candidates with ideal properties for artificial photosynthesis, offering significant advancement toward the conversion of sunlight into chemical fuels. [ABSTRACT FROM AUTHOR]

The semiconducting ZnO photosensitizer and the metalloid Ni 3 ZnC 0.7 catalyst are chemically bonded through oxygen-atom bridges, thereby expediting the photogenerated electron flow from ZnO to Ni 3 ZnC 0.7 , regulating the electron cloud density at the catalytic sites, and facilitating the conversion of *COOH-CO. [Display omitted] • Zn oxide –O–Zn TMC structure was constructed via ligand competition of MOF. • Zn oxide –O–Zn TMC integrates photoexcitation, reaction sites and electron transport channels. • Zn oxide –O–Zn TMC modulates the surface electron density distribution. • Zn oxide –O–Zn TMC structure promotes the conversion of *COOH–CO products. • CO yield was 2674.8 μmol g-1h−1 with selectivity of 93.4 %. Developing carbon dioxide (CO 2) photocatalysts from transition metal carbides (TMCs) with abundant active sites, modulable electron cloud density, as well as low cost and high stability is of great significance for artificial photosynthesis. Building an efficient electron transfer channel between the photo-excitation site and the reaction-active site to extract and steer photo-induced electron flow is necessary but challenging for the highly selective conversion of CO 2. In this study, we achieved an oxygen-bridged Schottky junction between ZnO and Ni 3 ZnC 0.7 (denoted as Zn oxide –O–Zn TMC) through a ligand-vacancy strategy of MOF. The ZnO–Ni 3 ZnC 0.7 heterostructure integrates the photo-exciter (ZnO), high-speed electron transport channel (Zn oxide –O–Zn TMC), and reaction-active species (Ni 3 ZnC 0.7), where Zn oxide –O–Zn TMC facilitates the transfer of excited electrons in ZnO to Ni 3 ZnC 0.7. The Zn atoms in Ni 3 ZnC 0.7 serve as electron-rich active sites, regulating the CO 2 adsorption energy, promoting the transformation of *COOH to CO, and inhibiting H 2 production. The ZnO–Ni 3 ZnC 0.7 shows a high CO yield of 2674.80 μmol g–1h–1 with a selectivity of 93.40 % and an apparent quantum yield of 18.30 % (λ = 420 nm) with triethanolamine as a sacrificial agent. The CO production rate remains at 96.40 % after 18 h. Notably, ZnO–Ni 3 ZnC 0.7 exhibits a high CO yield of 873.60 μmol g–1h–1 with a selectivity of 90.20 % in seawater. [ABSTRACT FROM AUTHOR]

Photoredox catalysis has attracted increasing attention because of wide range of synthetic transformations and solar energy conversion applications. Reviews on photoredox catalysis have so far focused predominantly on the synthetic applications. This review highlights how organic photoredox catalysts were developed and how they function as efficient photocatalysts in mechanistic point of views. In particular, 9‐mesityl‐10‐methylactidinium (Acr+–Mes) has been highlighted as one of the best organic photoredox catalysts. Acr+–Mes was originally developed as a model compound of the photosynthetic reaction center to mimic the long lifetime of the charge‐separated state in which the energy is converted to chemical energy in photosynthesis. The reason why Acr+–Mes acts as one of the most efficient photoredox catalyst is clarified in terms of the one‐electron redox potentials and long lifetimes of the electron‐transfer state (Acr•–Mes•+) produced upon photoexcitation of Acr+–Mes in different solvents. The reason why the mesityl substituent at the 9‐position of the Acr+ moiety is essential for the efficient photoredox catalysis is discussed in comparison with acridinium ions with different substituents R (Acr+–R) including 10‐methylacridinium ion with no substituent (AcrH+). The mechanisms of photoredox catalysis of Acr+–Mes are discussed in various synthetic transformations and solar energy conversion reactions mimicking photosynthesis. Photoredox catalysis of quinolinium ion and its derivatives is also discussed in comparison with that of Acr+–Mes. Finally, immobilization of Acr+–Mes and quinolinium ions to form the composite catalysts with redox catalyst is discussed to improve the photoredox catalytic activity and stability. [ABSTRACT FROM AUTHOR]

Lead-free halide perovskites (LFHP) are one of the most promising materials for CO 2 photoreduction; however, their stability is an issue that must be solved to scale up the manufacturing. To overcome this limitation, this work proposes the encapsulation of LFHP of K 3 Bi 2 I 9 in three inorganic supports based on aluminosilicates such as (i) geopolymer, (ii) tobermorite, and other based on (iii) magnesium oxychloride. These supports provide a porous structure and active sites to host the perovskite particles, which favor enhanced light absorption, stability, and their activity for CO 2 reduction under visible light. The encapsulated perovskites exhibited activity to photoconvert CO 2 into formic acid (HCOOH) with efficiencies up to 2500 μmol h−1 using the K 3 Bi 2 I 9 host in geopolymer. This support provides stable polysialate-diloxo chains to encapsulate the perovskite, delayed the degradation in aqueous medium, and its activity was demonstrated during 16 h of continuous visible light irradiation. The good stability and efficiency for CO 2 reduction was associated to the formation of K 3 Bi 2 I 9 /BiOI heterojunction that prevent the degradation of the structure and enhance the charge transfer between both semiconductors. • K 3 Bi 2 I 9 perovskite was encapsulated in inorganic supports to assure its stability. • The implementation of this approach allowed the stability of K 3 Bi 2 I 9 up to 16 h. • HCOOH was the main product of CO 2 reduction with high efficiencies (2.5 mmol h−1). • Partial leaching of K+ could enhanced the CO 2 sorption and the BiOI formation. • Geopolymer is an excellent K 3 Bi 2 I 9 host for stability and enhanced charge transfer. [ABSTRACT FROM AUTHOR]

Pyridinic N functionalized DEB-N 2 displays strong O 2 adsorption ability and delivers a substantial H 2 O 2 generation with an initial rate of 3492 μmol g-1h−1 in pure water. [Display omitted] Artificial photosynthesis of hydrogen peroxide (H 2 O 2) is a hopeful alternative to the industrial anthraquinone process. However, rational fabrication of the photocatalysts for the production of H 2 O 2 without any sacrificial agents is still a formidable challenge. Herein, two kinds of linear conjugated polymers (LCPs) including pyridinic N functionalized polymer (DEB-N 2) and pyridinic N non-contained polymer (DEB-N 0) were successfully synthesized. DEB-N 2 displays enhanced light capturing ability and good dispersion in water, leading to a substantial initial H 2 O 2 generation rate of 3492μmol g-1h−1 as well as remarkable photocatalytic stability in pure water. Furthermore, the temperature programmed desorption (TPD) and density functional theory (DFT) analysis reveal that highly electronegative pyridine-N atoms in DEB-N 2 boost the adsorption affinity of oxygen molecules, which facilitates the occurrence of the oxygen reduction reaction, therefore enhancing the performance of photocatalytic H 2 O 2 production. This study unveils that the presence of pyridinic N in DEB-N 2 has a significant impact on photocatalytic H 2 O 2 production, suggesting the precise manipulation of the chemical structure of polymer photocatalysts is essential to achieve efficient solar-to-chemical energy conversion. [ABSTRACT FROM AUTHOR]

Graphitized carbon nitride (C3N4)‐based photocatalysts provide a prospective approach for producing hydrogen peroxide (H2O2) in artificial photosynthesis. However, their activity is constrained by the sluggish water oxidation reaction (WOR) process, which hampers the supply of protons and electrons necessary for the oxygen reduction reaction. Here, this work demonstrates a synergistic redox dual‐site strategy via co‐modified with 3,4,9,10‐perylenetetracarboxylic acid diimide (PDI) and Pt single atoms in C3N4 support, which achieves an exceptional H2O2 yield of 802 µmol g−1 h−1 and a selectivity of 91.8% without sacrificial agents. Mechanistic studies reveal that Pt single atoms act as photogenerated electron‐rich sites to effectively activate O2 to form superoxide radicals, and PDI promotes WOR driving force to provide abundant protons. The optimized reduction and oxidation half‐reactions improve the proton‐coupled electron transfer process, thereby enhancing the selective photosynthesis of H2O2. This work underscores the importance of finely controlling half‐reactions in photocatalytic processes to promote efficient and synergistic overall reactions. [ABSTRACT FROM AUTHOR]

Converting clean solar energy into chemical energy through artificial photosynthesis is an effective solution to solve the energy and environmental issues. Here, we report a Cs3Bi2Br9/Bi2WO6 (CBB/BWO) Z‐scheme heterojunction constructed via electrostatic self‐assembly, which facilitates efficient separation of photogenerated carriers and ensures the corresponding redox capacity of both components. By sharing Bi atoms, a Br−Bi−O bond is established between CBB and BWO, serving as an "electron bridge". The electrons generated by BWO are efficiently channeled to CBB through the heterojunction‐formed "electron bridge", thereby achieving effective photocatalytic CO2 reduction. Under simulated sunlight conditions, it exhibits the highest CO yield of 72.52 μmol g−1 (without the addition of any precious metal, photosensitizers or sacrifices), which is approximately 7‐fold and 18‐fold greater than that of pure CBB and BWO, respectively. This work provides a more profound comprehension of the regulation of electron transfer through interfacial chemical bonds, thereby proposing a promising strategy for the development of efficient heterojunction photocatalysts for CO2 photoreduction. [ABSTRACT FROM AUTHOR]

Aquatic environments host various living organisms with active molecular systems, such as the enzymes in the thylakoid membrane that realise photosynthesis. Various challenges in achieving artificial photosynthesis, such as water splitting, have been studied using both inorganic and organic molecules. However, several problems persist, including diffusion-limited reactions and multiple redox reactions in the liquid phase. In this Feature Article, we discuss the significant challenges in using polymer networks as active mediators for photoinduced water splitting. In the creation of artificial chloroplasts, polymer networks offer various advantages, such as stable dispersions of multiple types of functional molecules and close molecular arrangements. To incorporate these features, stepwise synthesis and integration can be utilized during the hierarchical construction of polymer networks. The constituent molecules such as ruthenium complex and platinum nanoparticles in the photoinduced electron transfer circuits are closely arranged to smoothly operate forward reactions by polymer networks. The quantum efficiency of photoinduced H2 generation in gel systems is considerably higher than that of conventional solution systems. Additionally, a thermoresponsive poly(N-isopropylacrylamide) (PNIPAAm) network of microgels can be used to integrate catalytic nanoparticles into the inside by using the electrostatic interaction and the mesh size changes. By focusing on the redox changes of copolymerised molecules that induce swelling/shrinking at a constant temperature, active electron transfer can be precisely achieved using the coil–globule transition of the PNIPAAm having viologen. This article highlights the potential of polymer networks to develop strategies for active electron transfer and energy conversion systems similar to those found in living organisms. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

Efficient photocatalytic CO2 reduction coupled with the photosynthesis of pure H2O2 is a challenging and significant task. Herein, using classical CO2 photoreduction site iron porphyrinate as the linker, Ag(I) clusters were spatially separated and evenly distributed within a new metal–organic framework (MOF), namely Ag27TPyP‐Fe. With water as electron donors, Ag27TPyP‐Fe exhibited remarkable performances in artificial photosynthetic overall reaction with CO yield of 36.5 μmol g−1 h−1 and ca. 100 % selectivity, as well as H2O2 evolution rate of 35.9 μmol g−1 h−1. Since H2O2 in the liquid phase can be more readily separated from the gaseous products of CO2 photoreduction, high‐purity H2O2 with a concentration up to 0.1 mM was obtained. Confirmed by theoretical calculations and the established energy level diagram, the reductive iron(II) porphyrinates and oxidative Ag(I) clusters within an integrated framework functioned synergistically to achieve artificial photosynthesis. Furthermore, photoluminescence spectroscopy and photoelectrochemical measurements revealed that the robust connection of Ag(I) clusters and iron porphyrinate ligands facilitated efficient charge separation and rapid electron transfer, thereby enhancing the photocatalytic activity. [ABSTRACT FROM AUTHOR]

S‐scheme heterostructure photocatalysts, distinguished by unique charge‐transfer pathways and exceptional catalytic redox capabilities, have found widespread applications in addressing challenging chemical processes, including the photocatalytic reduction of CO2 with a high reaction barrier. Nevertheless, the influence of intraband defect levels within S‐scheme heterojunctions on charge separation, carrier lifetime, and surface catalytic reactions has, for the most part, been overlooked. Herein, we develop a tunable defect‐level‐assisted strategy to construct an electron reservoir, effectively prolonging the lifetime of charge carriers through the rapid capture and gradual release of photoelectrons within WO3‐x/In2S3 S‐scheme heterojunctions, as authenticated by femtosecond transient absorption spectroscopy and theoretical simulations. The surface photoredox mechanism, unraveled by Gibbs free energy calculations, demonstrates that oxygen‐vacancy‐induced defect states in WO3‐x/In2S3 heterojunctions unlock the rate‐determining H2O oxidation into free oxygen molecules by forming metastable oxygen intermediates, contributing to the facilitation of H2O photooxidation. This distinct role, combined with the extended carrier lifetime, results in boosted CO2 photoreduction with nearly 100 % CO selectivity in the absence of any photosensitizer or scavenger. Our work sheds light on the role of controllable defect levels in governing charge transfer dynamics within S‐scheme heterojunctions, thereby inspiring the development of more advanced photocatalysts for artificial photosynthesis. [ABSTRACT FROM AUTHOR]

As the global energy crisis deepens and the demand for carbon emission reductions grows more urgent, the rapid development of artificial photosynthesis (AP) emerges as a critical solution. AP offers a sustainable method for producing hydrogen and electrical energy by mimicking natural photosynthetic processes. The field continues to expand, with new advances and research findings emerging each year. This paper provides a comprehensive review of recent breakthroughs in AP, with a particular focus on the development of advanced catalysts designed to optimize solar-driven water-splitting processes. Eight types of catalysts, published in recent studies, are analyzed and compared for their efficiency and potential impact. Additionally, various methods for generating molecular hydrogen, including artificial photosynthesis, are evaluated to highlight their advantages and challenges. Crucially, this review also addresses the need for efficient hydrogen storage systems, a key component in advancing renewable energy technologies. The study concludes by outlining essential directions for future research aimed at enhancing the reliability, scalability, and efficiency of artificial photosynthesis, paving the way for its integration into global energy solutions. [Display omitted] • Energy transformations in natural and artificial photosynthesis are compared. • Ongoing research in artificial photosynthesis is highlighted. • The role of artificial photosynthesis in hydrogen energy sustainability is explored. • Challenges and future potentials in artificial photosynthesis are addressed. [ABSTRACT FROM AUTHOR]

A nonporous [Pb(tadt)]n (tadt = 1,3,4‐thiadiazole‐2,5‐dithiolate) coordination polymer, KGF‐9, with a 2D infinite (−Pb−S−)n structure has been previously reported as a precious‐metal‐free photocatalyst for selective CO2‐to‐formate conversion under visible light. In the present work, a microwave (MW)‐assisted solvothermal reaction is used to synthesize KGF‐9 with improved physicochemical properties and catalytic activity. Compared with KGF‐9 prepared by the previously reported methods, that prepared by the new synthesis route exhibited a greater specific surface area, greater crystallinity, and greater photoconductivity. These improved properties led to a drastic increase of the apparent quantum yield (AQY) for selective formate production, from 2.6 to 25% at 400 nm; this AQY represents a record‐high value among reported heterogeneous photocatalysts for CO2‐to‐formate conversion. Interestingly, the AQY for formate production is unchanged irrespective of the light intensity (0.04–14 mW cm−2), indicating little contribution of charge accumulation in the bulk during the reaction (i.e., indicating efficient charge transport to surface reactants). When composited with Ketjen Black, KGF‐9 enabled the electrochemical conversion of CO2 to formate in aqueous solution while maintaining a high selectivity. A high‐rate reduction of CO2 to formate with a total absolute current density of 200–300 mA cm−2 is achieved, with a Faradaic efficiency (FE) of >90%. [ABSTRACT FROM AUTHOR]

The photosynthetic pigment "chlorophyll" possesses attractive photophysical properties, including efficient sunlight absorption, photoexcited energy transfer, and charge separation, which are advantageous for applications for photo- and electro-functional materials such as artificial photosynthesis and solar cells. However, these functions cannot be realized by individual chlorophyll molecules alone; rather, they are achieved by the formation of sophisticated supramolecules through the self-assembly of the pigments. Here, we present strategies for constructing and developing artificial light-harvesting systems by mimicking photosynthetic antenna complexes through the highly ordered supramolecular self-assembly of synthetic dyes, particularly chlorophyll derivatives. [ABSTRACT FROM AUTHOR]

The direct utilization of solar energy for the artificial photosynthesis of hydrogen peroxide (H2O2) provides a reliable approach for producing this high-value green oxidant. Here we report on the utility of high-entropy oxide (HEO) semiconductor as an all-in-one photocatalyst for visible light-driven H2O2 production directly from H2O and atmospheric O2 without the need of any additional cocatalysts or sacrificial agents. This high-entropy photocatalyst contains eight earth-abundant metal elements (Ti/V/Cr/Nb/Mo/W/Al/Cu) homogeneously arranged within a single rutile phase, and the intrinsic chemical complexity along with the presence of a high density of oxygen vacancies endow high-entropy photocatalyst with distinct broadband light harvesting capability. An efficient H2O2 production rate with an apparent quantum yield of 38.8% at 550 nm can be achieved. The high-entropy photocatalyst can be readily assembled into floating artificial leaves for sustained on-site production of H2O2 from open water resources under natural sunlight irradiation. An "all-in-one" high-entropy semiconductor photocatalyst enables the photocatalytic production of H2O2 from H2O and O2 under visible light without any external cocatalysts or sacrificial agents [ABSTRACT FROM AUTHOR]

BACKGROUND: Natural photosynthesis, utilizing intelligent molecular machinery to harness sunlight, stands as the benchmark for efficient energy generation. Despite its high quantum efficiency compared to synthetic methods, challenges persist due to dynamic nutritional and light requirements in plant, microalgae, and cyanobacteria‐driven processes. Reported microalgae CO2 uptake rates rely on biomass dry cell weight measurement after certain incubation period and systematic study of required CO2 concentrations for optimal photobioreactor operation remaining unexplored. This research is thus aimed at evaluating the critical dissolved CO2 (Ccrit ∙ CO2) concentration and specific CO2 uptake rates (SCUR) of Chlorella minutissima (CM) culture in the presence of surplus light and other nutrients by online monitoring and measuring the dynamic CO2 uptake rates which will help in maintaining the optimal rate of CO2 delivery for continuous cultivation of microalgae while minimizing the escape of CO2. RESULTS: Dissolved Ccrit ∙ CO2 was determined to be in the range of 16–20 mg/L, and the maximum SCUR in BBM (Bold Basal Medium) was found to be 0.73 mg CO2 (mg dcw ∙ h)−1. Interestingly, this SCUR value is nearly three times greater than that of the most efficient in vitro artificial photosynthetic novel pathway reported so far. CONCLUSION: From the calculated SCUR values, it may be noted that 9.6 g of biomass can be obtained from 1 g of microalgal inoculum in a day, thereby setting a benchmark for the scientists working in the areas of bioprocess engineering, synthetic biology, and metabolic engineering to comply. © 2024 Society of Chemical Industry (SCI). [ABSTRACT FROM AUTHOR]

Metal-organic layers (MOLs), a type of new-emerging two-dimensional ultrathin metal-organic framework materials with large surface areas and highly exposed active sites, have shown promising applications in photocatalytic CO2 reduction. However, due to a lack of photosensitivity and photooxidation capability, photosensitizers and sacrificial reductants are usually necessary for MOLs-based photocatalytic CO2 reduction systems. In this article, by integration of MOLs and quantum dots (QDs), we constructed MOLs-based catalysts with multi-functions of photosensitivity, photoreduction and photooxidation, which thus can serve as photocatalysts for CO2 reduction with H2O as an electron donor. Specifically, by an electrostatic self-assembly approach, nickel(II)-based MOLs (Ni-MOLs) and CsPbBr3 QDs have been assembled, constructing valid II-Scheme Ni-MOLs/CsPbBr3 heterojunctions with close Ni-MOLs/CsPbBr3 heterointerface. Such a close heterointerface shortens the charge transfer distance, thus effectively boosting the charge separation and transfer. As a result, upon illumination by visible light (λ ⩾ 400 nm, 100 mW cm−2), the optimized photocatalyst shows high efficiency and stability in photochemical CO2 reduction in the absence of any photosensitizers and sacrificial reductants. The CO yield reaches as high as 124 µmol g−1 in 4 h, over 6 times higher than that achieved by CsPbBr3. Additionally, the selectivity reaches 100%. This work provides a new way to construct MOL-based catalysts for artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Graphitic carbon nitride (g-C3N4) has gained increasing attention in artificial photosynthesis of H2O2, yet its performance is hindered by sluggish oxygen reduction reaction (ORR) kinetics and short excited-state electron lifetimes. Here we show a B-doped g-C3N4 (BCN) tailored with coordinatively unsaturated FeOOH and CoOx clusters for H2O2 photosynthesis from water and oxygen without sacrificial agents. The optimal material delivers a 30-fold activity enhancement compared with g-C3N4 under visible light, with a solar-to-chemical conversion efficiency of 0.75%, ranking among the forefront of reported g-C3N4-based photocatalysts. Additionally, an electron transfer efficiency reaches 34.1% for the oxygen reduction reaction as revealed by in situ microsecond transient absorption spectroscopy. Experimental and theoretical results reveal that CoOx initiates hole–water oxidation and prolongs the electron lifetime, whereas FeOOH accepts electrons and promotes oxygen activation. Intriguingly, the key to the direct one-step two-electron reaction pathway for H2O2 production lies in coordinatively unsaturated FeOOH to adjust the Pauling-type adsorption configuration of O2 to stabilize peroxide species and restrain the formation of superoxide radicals. The authors develop a strategy to regulate oxygen reduction reaction kinetics and electron lifetimes with coordinatively unsaturated FeOOH and CoOx clusters to access a direct two-electron pathway for H2O2 photosynthesis on boron-doped g-C3N4. [ABSTRACT FROM AUTHOR]

Natural photosynthesis utilizes solar energy to convert water and atmospheric CO2 into carbohydrates through all-weather light/dark reactions based on molecule-based enzymes and coenzymes, inspiring extensive development of artificial photosynthesis. However, development of efficient artificial photosynthetic systems free of noble metals, as well as rational integration of functional units into a single system at the molecular level, remain challenging. Here we report an artificial system, the assembly system of Cu6 cluster and cobalt terpyridine complex, that mimics natural photosynthesis through precise integration of nanozyme complexes and ubiquinone (coenzyme Q) on Cu6 clusters. This biomimetic system efficiently reduces CO2 to CO in light reaction, achieving a production rate of 740.7 μmol·g−1·h−1 with high durability for at least 188 hours. Notably, our system realizes the decoupling of light and dark reactions, utilizing the phenol-evolutive coenzyme Q acting as an electron reservoir. By regulating the stabilizer of coenzyme Q, the dark reaction time can be extended up to 8.5 hours, which fully meets the natural day/night cycle requirements. Our findings advance the molecular design of artificial systems that replicate the comprehensive functions of natural photosynthesis. Natural photosynthesis converts H2O and CO2 into carbohydrates through all-weather reactions based on enzymes and coenzymes. Here, the authors report an artificial photosynthesis system under intermittent light irradiation by integrating nanozyme complexes and ubiquinone on a copper nanocluster. [ABSTRACT FROM AUTHOR]

To achieve artificial photosynthesis, it is crucial to develop a catalytic system for CO2 reduction using water as the electron source. However, photochemical CO2 reduction by homogeneous molecular catalysts has predominantly been conducted in organic solvents. This study investigates the impact of water content on catalytic activity in photochemical CO2 reduction in N,N-dimethylacetamide (DMA), using [Ru(bpy)3]2+ (bpy: 2,2′-bipyridine) as a photosensitizer, 1-benzyl-1,4-dihydronicotinamide (BNAH) as an electron donor, and two ruthenium diimine carbonyl complexes, [Ru(bpy)2(CO)2]2+ and trans(Cl)-[Ru(Ac-5Bpy-NHMe)(CO)2Cl2] (5Bpy: 5′-amino-2,2′-bipyridine-5-carboxylic acid), as catalysts. Increasing water content significantly decreased CO and formic acid production. The similar rates of decrease for both catalysts suggest that water primarily affects the formation efficiency of free one-electron-reduced [Ru(bpy)3]2+, rather than the intrinsic catalytic activity. The reduction in cage-escape efficiency with higher water content underscores the challenges in replacing organic solvents with water in photochemical CO2 reduction. [ABSTRACT FROM AUTHOR]

Selective CO2 photoreduction to value‐added multi‐carbon (C2+) feedstocks, such as C2H4, holds great promise in direct solar‐to‐chemical conversion for a carbon‐neutral future. Nevertheless, the performance is largely inhibited by the high energy barrier of C−C coupling process, thereby leading to C2+ products with low selectivity. Here we report that through facile surface immobilization of a 1‐ethyl‐3‐methylimidazolium tetrafluoroborate (EMIM‐BF4) ionic liquid, plasmonic Cu nanowires could enable highly selective CO2 photoreduction to C2H4 product. At an optimal condition, the resultant plasmonic photocatalyst exhibits C2H4 production with selectivity up to 96.7 % under 450 nm monochromatic light irradiation, greatly surpassing its pristine Cu counterpart. Combined in situ spectroscopies and computational calculations unravel that the addition of EMIM‐BF4 ionic liquid modulates the local electronic structure of Cu, resulting in its enhanced adsorption strength of *CO intermediate and significantly reduced energy barrier of C−C coupling process. This work paves new path for Cu surface plasmons in selective artificial photosynthesis to targeted products. [ABSTRACT FROM AUTHOR]

Resorcinol‐formaldehyde (RF) resin represents a promising visible‐light responding photocatalyst for oxygen reduction reaction (ORR) toward H2O2 production. However, its photocatalytic ORR activity toward H2O2 generation is still unsatisfied for practical application. Herein, 3‐hydroxythiophenol‐formaldehyde (3‐HTPF) resin microspheres synthesized through polycondensation reaction between 3‐HTP and formaldehyde at room temperature and subsequent hydrothermal treatment exhibit enhanced photocatalytic ORR activity is reported. The experimental results show that the partial substitution of hydroxy group (─OH) by sulfhydryl one (─SH) through using 3‐HTP to replace resorcinol could slow the rates of nucleation and growth of the resin particles and lead to strongly π‐stacked architecture in 3‐HTPF. The introduction of ─SH group can also improve adsorption ability of 3‐HTPF to O2 molecules and enhance ORR catalytic activity of the photocatalysts. Stronger built‐in electric field, better adsorption ability to O2 molecules, and increased surface catalytic activity collectively boost photocatalytic activity of 3‐HTPF microspheres. As a result, H2O2 production rate of 2010 µm h−1 is achieved over 3‐HTPF microspheres at 273 K, which is 3.4 times larger than that obtained using RF submicrospheres (591 µm h−1). The rational substituent group modulation provides a new strategy for designing polymeric photocatalysts at the molecular level toward high‐efficiency artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Resorcinol‐formaldehyde (RF) resin represents a promising visible‐light responding photocatalyst for oxygen reduction reaction (ORR) toward H2O2 production. However, its photocatalytic ORR activity toward H2O2 generation is still unsatisfied for practical application. Herein, 3‐hydroxythiophenol‐formaldehyde (3‐HTPF) resin microspheres synthesized through polycondensation reaction between 3‐HTP and formaldehyde at room temperature and subsequent hydrothermal treatment exhibit enhanced photocatalytic ORR activity is reported. The experimental results show that the partial substitution of hydroxy group (─OH) by sulfhydryl one (─SH) through using 3‐HTP to replace resorcinol could slow the rates of nucleation and growth of the resin particles and lead to strongly π‐stacked architecture in 3‐HTPF. The introduction of ─SH group can also improve adsorption ability of 3‐HTPF to O2 molecules and enhance ORR catalytic activity of the photocatalysts. Stronger built‐in electric field, better adsorption ability to O2 molecules, and increased surface catalytic activity collectively boost photocatalytic activity of 3‐HTPF microspheres. As a result, H2O2 production rate of 2010 µm h−1 is achieved over 3‐HTPF microspheres at 273 K, which is 3.4 times larger than that obtained using RF submicrospheres (591 µm h−1). The rational substituent group modulation provides a new strategy for designing polymeric photocatalysts at the molecular level toward high‐efficiency artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Natural photosynthetic systems require spatiotemporal organization to optimize photosensitized reactions and maintain overall efficiency, involving the hierarchical self‐assembly of photosynthetic components and their stabilization through synergistic interactions. However, replicating this level of organization is challenging due to the difficulty in efficiently communicating supramolecular nano‐assemblies with nanoparticles or biological architectures, owing to their dynamic instability. Herein, we demonstrate that the supramolecular reconstruction of self‐assembled amphiphilic rhodamine B nanospheres (RN) through treatment with metal‐phenolic coordination complexes results in the formation of a stable hybrid structure. This reconstructed structure enhances electron transfer efficiency, leading to improved photocatalytic performance. Due to the photoluminescence quenching property of RN and its electronic synergy with tannic acid (T) and zirconium (Z), the supramolecular complexes of hybrid nanospheres (RNTxZy) with Pt nanoparticles or a biological workhorse, Shewanella oneidensis MR‐1, showed marked improvement in photocatalytic hydrogen production. The supramolecular hybrid particles with a metal‐phenolic coordination layer showed 5.6‐ and 4.0‐fold increases, respectively, in the productivities of hydrogen evolution catalyzed by Pt (Pt/RNTxZy) and MR‐1 (M/RNTxZy), respectively. These results highlight the potential for further advancements in the structural and photochemical control of supramolecular nanomaterials for energy harvesting and bio‐hybrid systems. [ABSTRACT FROM AUTHOR]

Directly converting CO2 in flue gas using artificial photosynthetic technology represents a promising green approach for CO2 resource utilization. However, it remains a great challenge to achieve efficient reduction of CO2 from flue gas due to the decreased activity of photocatalysts in diluted CO2 atmosphere. Herein, we designed and synthesized a series of dual metallosalen‐based covalent organic frameworks (MM‐Salen‐COFs, M: Zn, Ni, Cu) for artificial photosynthetic diluted CO2 reduction and confirmed their advantage in comparison to that of single metal M‐Salen‐COFs. As a results, the ZnZn‐Salen‐COF with dual Zn sites exhibits a prominent visible‐light‐driven CO2‐to‐CO conversion rate of 150.9 μmol g−1 h−1 under pure CO2 atmosphere, which is ~6 times higher than that of single metal Zn‐Salen‐COF. Notably, the dual metal ZnZn‐Salen‐COF still displays efficient CO2 conversion activity of 102.1 μmol g−1 h−1 under diluted CO2 atmosphere from simulated flue gas conditions (15 % CO2), which is a record high activity among COFs‐ and MOFs‐based photocatalysts under the same reaction conditions. Further investigations and theoretical calculations suggest that the synergistic effect between the neighboring dual metal sites in the ZnZn‐Salen‐COF facilitates low concentration CO2 adsorption and activation, thereby lowering the energy barrier of the rate‐determining step. [ABSTRACT FROM AUTHOR]

Water oxidation is a crucial reaction in the artificial photosynthesis system. In the present work, density functional calculations were employed to decipher the mechanism of water oxidation catalyzed by a binuclear cobalt complex, which was disclosed to be a homogeneous water oxidation catalyst in pH=7 phosphate buffer. The calculations showed that the catalytic cycle starts from the CoIII,III−OH2 species. Then, a proton‐coupled electron transfer followed by a one‐electron transfer process leads to the generation of the formal CoIV,IV−OH intermediate. The subsequent PCET produces the active species, namely the formal CoIV,V=O intermediate (4). The oxidation processes mainly occur on the ligand moiety, including the coordinated water moiety, implying a redox non‐innocent behavior. Two cobalt centers keep their oxidation states and provide one catalytic center for water activation during the oxidation process. 4 triggers the O−O bond formation via the water nucleophilic attack pathway, in which the phosphate buffer ion functions as the proton acceptor. The O−O bond formation is the rate‐limiting step with a calculated total barrier of 17.7 kcal/mol. The last electron oxidation process coupled with an intramolecular electron transfer results in the generation of O2. [ABSTRACT FROM AUTHOR]

Solar-driven CO2 conversion into high-value-added chemicals, powered by photovoltaics, is a promising technology for alleviating the global energy crisis and achieving carbon neutrality. However, most of these endeavors focus on CO2 electroreduction to small-molecule fuels such as CO and ethanol. In this paper, inspired by the photosynthesis of green plants and artificial photosynthesis for the electroreduction of CO2 into value-added fuel, CO2 artificial photosynthesis for the electrocarboxylation of bromobenzene (BB) with CO2 to generate the value-added carboxylation product methyl benzoate (MB) is demonstrated. Using two series-connected dye-sensitized photovoltaics and high-performance catalyst Ag electrodes, our artificial photosynthesis system achieves a 61.1% Faraday efficiency (FE) for carboxylation product MB and stability of the whole artificial photosynthesis for up to 4 h. In addition, this work provides a promising approach for the artificial photosynthesis of CO2 electrocarboxylation into high-value chemicals using renewable energy sources. [ABSTRACT FROM AUTHOR]

The use of organic molecules as photosensitizers in photoredox catalysis is an attractive research field as it has the potential to replace conventionally used photosensitizers, which are based on rare metals. In the context of light‐driven hydrogen evolution catalysis, the radical formation of two perylene monoimide dyes (PMIs) was studied by means of electron paramagnetic resonance (EPR) and UV/Vis spectroscopy. The PMIs were reduced and oxidized both photochemically and electrochemically to study the changes in absorption and EPR signature. A distinct differentiation between the two PMIs as well as a comparison between the oxidative and reductive processes can be made by EPR measurements. UV/Vis measurements showed different features under redox conditions. This study addresses a gap in understanding the radical intermediate formation during photocatalytic processes. [ABSTRACT FROM AUTHOR]

Here, the use of high‐performance microfluidic techniques (HPMT) is reportedto afford conjugated porous polymer (CPPs) with smaller particle size and narrower particle size dispersion than the obtained by miniemulsion methodology. Specifically, polymers based on BODIPY or BOPHY dyes are synthesized by HPMT conditions and conventional miniemulsion conditions. The polymer textural properties from HPMT are notably improved, giving rise to high‐quality thin films that are photoelectrochemically characterized. Furthermore, hybrid materials of CPPs synthesized by HPMT and TiO2 inorganic semiconductor revealed enhanced photocatalytic activity in the hydrogen evolution reaction (HER). The most active hybrid UN_IEP‐7@T‐10 photocatalyst, containing 10 wt% polymer loading, achieved a hydrogen evolution rate of 3.10 mmol g−1 h−1 (ƺ = 1.13%), which is threefold higher than that of its non‐nanostructured from bulk synthesis, two‐times greater than its nanostructured by conventional miniemulsion techniques and even surpassed by 39‐times the performance of bare TiO2. It is noteworthy that both photoluminescence lifetime (τPL) and transient lifetime (τT) are not affected by the nanoestructuration of CPPs, which agrees with the preservation of the chemical structure by both synthetic methodologies. The employment of HPMT as nanostructuration strategy clearly supports the obtaining of more processable polymers for a wide range of energy applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • We show an easy, template-free synthesis of polymeric photocatalysts with hollow nanotube-nanocluster core–shell structure. • The structure is realized via intramolecular covalent crosslinking and synergistic intermolecular donor–acceptor interactions. • This approach facilitated charge separation and transfer, reduced nanocluster aggregation, and provided more catalytic sites. The modulation of microstructures in conjugated polymers represents a viable strategy for enhancing photocatalytic efficiency, albeit hampered by complex processing techniques. Here, we present an uncomplicated, template-free method to synthesize polymeric photocatalysts, namely BCN(x)@PPy, featuring a hollow nanotube-nanocluster core–shell superstructure. This configuration is realized through intramolecular covalent crosslinking and synergistic intermolecular donor–acceptor (D−A) interactions between phenylene pyrene (PPy, D) nanotubes and poly([1,1′-biphenyl]-3-carbonitrile) (PBCN, A) nanoclusters. Interestingly, the optimized BCN2@PPy composite demonstrates remarkably enhanced performance for photocatalytic hydrogen evolution, with an efficiency of 14.7-fold higher than that of unmodified PPy nanotubes. Experimental and density functional theory calculations revealed that BCN(x)@PPy composites are conducive to shortening photogenerated exciton migration, facilitating charge separation and transfer, reducing nanoclusters aggregation or re-stacking, and providing sufficient catalytically active sites, all contributing to the heightened efficiency in photocatalysis. These insights underscore the potential for precise molecular adjustments in conjugated polymers, advancing artificial photosynthesis. [ABSTRACT FROM AUTHOR]

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Abnormal hyperphosphorylation of tau protein is a principal pathological hallmark in the onset of neurodegenerative disorders, such as Alzheimer's disease (AD), which can be induced by an excess of reactive oxygen species (ROS). As an antioxidant, hydrogen gas (H2) has the potential to mitigate AD by scavenging highly harmful ROS such as •OH. However, conventional administration methods of H2 face significant challenges in controlling H2 release on demand and fail to achieve effective accumulation at lesion sites. Herein, we report artificial nanoreactors that mimic natural photosynthesis to realize near-infrared (NIR) light-driven photocatalytic H2 evolution in situ. The nanoreactors are constructed by biocompatible crosslinked vesicles (CVs) encapsulating ascorbic acid and two photosensitizers, chlorophyll a (Chla) and indoline dye (Ind). In addition, platinum nanoparticles (Pt NPs) serve as photocatalysts and upconversion nanoparticles (UCNP) act as light-harvesting antennas in the nanoreacting system, and both attach to the surface of CVs. Under NIR irradiation, the nanoreactors release H2 in situ to scavenge local excess ROS and attenuate tau hyperphosphorylation in the AD mice model. Such NIR-triggered nanoreactors provide a proof-of-concept design for the great potential of hydrogen therapy against AD.

Enhancing the utilization of absorbed light is essential for enhancing the efficiency of solar energy conversion via artificial photosynthesis. In this work, we report the successful incorporation of Rhodamine B (RhB) into the pore of ZIF-8 (ZIF = zeolitic imidazolate framework) and the efficient energy transfer process from RhB to Co-doped ZIF-8. Using transient absorption spectroscopy, we show that energy transfer only occurs from RhB (donor) to Co center (acceptor) when RhB is confined into the ZIF-8 structure, which is in stark contrast to the system based on the physical mixture of RhB with Co-doped ZIF-8, where negligible energy transfer was observed. In addition, energy transfer efficiency increases with the concentration of Co and reaches a plateau when the molar ratio of Co to RhB reaches 32. These results suggest that RhB confined in the ZIF-8 structure is essential for energy transfer to occur, and energy transfer efficiency can be controlled by tuning the concentration of acceptors. [ABSTRACT FROM AUTHOR]

The adsorption ability of O 2 and OOH* on the Au site can be enhanced to improve photocatalytic H 2 O 2 production by constructing an electron-deficient Auδ+ site. [Display omitted] • Au nanoparticles were constructed by a Pt-induced selective photodeposition method. • The charge spontaneously transfers to produce the electron-deficient Auδ+ active site. • Auδ+ nanoparticles spontaneously enhance the intensity and number of O 2 adsorption. • The BiVO 4 /Pt 0.1 @Au exhibits high photocatalytic H 2 O 2 -production activity. Simultaneous optimization of the number and intensity of oxygen (O 2) adsorption on gold (Au) cocatalyst is highly required to greatly improve their interfacial hydrogen peroxide (H 2 O 2)-production activity. However, it is a great challenge to realize the above effective modulation of Au by traditional photodeposition route. In this study, a platinum (Pt)-induced selective photodeposition method was designed to simultaneously regulate the particle size and electronic structure of Au cocatalyst for boosting the photocatalytic H 2 O 2 -production activity of bismuth vanadate (BiVO 4) via the selective deposition of Pt@Au core–shell cocatalyst. The photocatalytic results indicate that the as-prepared BiVO 4 /Pt 0.1 @Au photocatalyst achieves a considerable H 2 O 2 -production activity with a rate of 2752.13 μmol L−1 (AQE = 13.76 %), which is obviously higher than that of BiVO 4 /Pt (137.63 μmol L−1) and BiVO 4 /Au (475.33 μmol L−1). It was found that the introduction of Pt successfully induced the formation of Au nanoparticles for enhancing the number of O 2 adsorption. Meanwhile, the spontaneous transfer of free electrons of Au to Pt induces the generation of electron-deficient Auδ+ sites, which spontaneously enhances the O 2 -adsorption intensity for facilitating the 2-electron oxygen reduction reaction (ORR), resulting in efficient H 2 O 2 production. The present strategy may be useful for more comprehensively regulating the intensity and number of O 2 adsorption on cocatalysts to facilitate artificial photosynthesis. [ABSTRACT FROM AUTHOR]

[Display omitted] Photocatalytic reduction of CO 2 in pure H 2 O media to produce chemicals presents an appealing avenue for simultaneously alleviating energy and environmental crises. However, the rapid recombination of photogenerated charge carriers presents a significant challenge in this promising field. Heterojunction engineering has emerged as an effective approach to address this dilemma. Here, by decorating 2D NiAl-layered double hydroxides (NAL) onto bismuth oxybromide (BOB), we have created a S-scheme heterojunction (N 1 B 1 composite). This catalyst affords CO 2 -to-CO yields of 102.30 μmol g−1 with a selectivity of 100 %. Ultraviolet photoelectron spectroscopy (UPS) and in-situ irradiated X-ray photoelectron spectroscopy (ISI-XPS) reveal that charge transfer occurs efficiently from BOB to 2D-NAL upon light irradiation. The designed N 1 B 1 heterojunction achieves 7.3-fold and 2.1-fold increase in the internal electric field strength compared to bare 2D-NAL and BOB, respectively, which should be accountable for the improved charge migration. Additionally, pulsed chemisorption and in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) show the presence of multiple carbonate intermediates with activated O C O bonds upon N 1 B 1 composite, with *CO 2 − being identified as the most crucial species for CO production. [ABSTRACT FROM AUTHOR]

[Display omitted] • A robust 2D/2D MXene/C 3 N 5 heterostructured artificial photosynthesis platform. • Nitrogen-rich C 3 N 5 nanosheets with abundant π-π conjugated electrons. • Abundant ultrathin 2D/2D hetero-interfaces for rapid charge separation/transfer. • Nearly 100 % photocatalytic NADH regeneration efficiency without electron mediator. • Ultra-high HCOOH production rate of 3.51 mmol g−1h−1 with nearly 100 % selectivity. Photoenzyme-coupled catalytic systems offer a promising avenue for selectively converting CO 2 into high-value chemicals or fuels. However, two key challenges currently hinder their widespread application: the heavy reliance on the costly coenzyme NADH, and the necessity for metal-electron mediators or photosensitizers to address sluggish reaction kinetics. Herein, we present a robust 2D/2D MXene/C 3 N 5 heterostructured artificial photosynthesis platform for in situ NADH regeneration and photoenzyme synergistic CO 2 conversion to HCOOH. The efficiencies of utilizing and transmitting photogenerated charges are significantly enhanced by the abundant π-π conjugation electrons and well-engineered 2D/2D hetero-interfaces. Noteworthy is the achievement of nearly 100 % NADH regeneration efficiency within just 2.5 h by 5 % Ti 3 C 2 /C 3 N 5 without electron mediators, and an impressive HCOOH production rate of 3.51 mmol g−1h−1 with nearly 100 % selectivity. This study represents a significant advancement in attaining the highest NADH yield without electron mediator and provides valuable insights into the development of superior 2D/2D heterojunctions for CO 2 conversion. [ABSTRACT FROM AUTHOR]

Heterojunction engineering has been deemed one of the most promising strategies for promoting charge separation and improving solar‐to‐chemicals efficiency. Howbeit, constructing well‐defined nanoheterojunction with superior photocatalytic activity for H2O2 generation and a clear reaction mechanism remains a formidable challenge. Herein, an in situ vulcanization way to synthesize an intriguing 2D/1D Bi3TiNbO9/Bi2S3 heterojunction by growing Bi2S3 nanorods on Bi3TiNbO9 microsheet is used for the first time, where an S‐scheme charge transfer mechanism is formed that facilitates the spatial separation of charge carriers. Moreover, the in situ grown Bi2S3 on Bi3TiNbO9 can optimize the interfacial electronic structure and the reaction energy barriers. As a result, the H2O2 yield rate for Bi3TiNbO9/Bi2S3 can reach 810(2) µmol g−1 h−1 without any sacrificial agents and cocatalysts, ≈6.18 and ≈18.0 times of pristine Bi3TiNbO9 and Bi2S3, respectively. Importantly, the heterojunction unveiled unprecedented stability, remaining ≈95.46(2)% of the initial one after 13 continuous cycles. This work highlights an innovative in situ vulcanization strategy to engineer oxide perovskite/metal sulfide nanocomposite catalysts for artificial photosynthesis of H2O2, opening new opportunities for achieving highly efficient photocatalyst systems. [ABSTRACT FROM AUTHOR]

Artificial photosynthesis emerges as a strategic pathway to produce hydrogen peroxide (H2O2), an environmentally benign oxidant and a clean energy carrier. Nonetheless, in many heterojunction‐based artificial photosynthetic systems, the H2O2 productivity is significantly hindered by poor carrier transport, narrow spectral light absorption, and a lack of adequate active sites for the two‐electron oxygen reduction reaction. Herein, a catalyst architecture with an iso‐elemental heterojunction formed by interfacing Zn3In2S6 nano‐flowers and ZnIn2S4 nanosheets is proposed. This catalyst exhibits a H2O2 production rate as high as 23.47 µmol g−1 min−1 under UV–vis light irradiation, which is attributed to the minimized contact energy barrier and enhanced lattice match at the ZnIn2S4/Zn3In2S6 interface thanks to the iso‐elemental catalyst architecture which aids in enhanced efficient separation and transfer of photogenerated carriers. Theoretical simulations alongside comprehensive in‐situ and ex‐situ characterizations confirm the photo‐redox sites for H2O2 generation and effective carrier dynamics across the catalyst surface. Moreover, substituting one reduction‐type catalyst ZnIn2S4 with other non‐iso‐elemental catalysts like CdIn2S4, TiO2, and CdS further confirms the feasibility and superiority of the proposed iso‐elemental configuration. This work offers a new perspective on designing heterojunction catalysts for artificial photosynthesis of H2O2. [ABSTRACT FROM AUTHOR]

Atmospheric CO2 and H2O adsorbed on the photocatalyst surface undergo sunlight‐assisted conversion to solar products that bridge the gaps between artificial and natural photosynthesis. Herein, we report a Lewis acid‐base interaction derived photocatalyst, Cu deposited on reduced titania, that harvests CO2 and H2O from the air and transforms them to CH4. Photocatalyst surface studies confirm that coordinately unsaturated Cu atoms and oxygen vacancies are formed that facilitate CO2 and H2O adsorption. The mechanistic studies, combined with tandem secondary ion mass spectroscopy and isotopic labelling, confirm the CH4 origin from atmosphere‐adsorbed CO2 and H2O. The contributing factors to photocatalyst instability are explored. We expect that this study will have an impact on the widespread application and economic viability of photocatalytic CO2 reduction. [ABSTRACT FROM AUTHOR]

The photosynthetic oxygen‐evolving center (OEC) is a unique Mn4CaO5‐cluster that catalyses water splitting into electrons, protons, and dioxygen. Precisely structural and functional mimicking of the OEC is a long‐standing challenge and pressingly needed for understanding the structure‐function relationship and catalytic mechanism of O−O bond formation. Herein we report two simple and robust artificial Mn3Ce2O5‐complexes that display a remarkable structural similarity to the OEC in regarding of the ten‐atom core (five metal ions and five oxygen bridges) and the alkyl carboxylate peripheral ligands. This Mn3Ce2O5‐cluster can catalyse the water‐splitting reaction on the surface of ITO electrode. These results clearly show that cerium can structurally and functionally replace both calcium and manganese in the cluster. Mass spectroscopic measurements demonstrate that the oxide bridges in the cluster are exchangeable and can be rapidly replaced by the isotopic oxygen of H218O in acetonitrile solution, which supports that the oxide bridge(s) may serve as the active site for the formation of O−O bond during the water‐splitting reaction. These results would contribute to our understanding of the structure‐reactivity relationship of both natural and artificial clusters and shed new light on the development of efficient water‐splitting catalysts in artificial photosynthesis. [ABSTRACT FROM AUTHOR]

The construction of solar‐to‐chemical conversion system by mimicking the photosynthetic network of the chloroplast holds great promise on efficient solar energy utilization. We developed an artificial photosynthetic cell (APC) based on molecular biomimetic thylakoid (CoTPP‐FePy) to split water into hydrogen and oxygen (H2 and O2) at low driving voltage (1.1 V) and neutral condition (pH≈7). The CoTPP‐FePy can emulate the light reaction in thylakoids to produce O2 by coupling light harvesting, photocatalysis, and electron/energy storage (FeIII/FeII−Py). Subsequently, a membrane electrode assembly (MEA) were employed to simulate the dark reaction, wherein the proton, electron and energy generated by the light reaction can drive the H2 producing process. By a temporally and spatially coupling of the light and dark reactions, the resulting APC achieved a solar conversion efficiency of 3.1 %, exceeding that of natural photosynthetic systems and demonstrating the potential of artificial photosynthesis. [ABSTRACT FROM AUTHOR]

Proton supply is as critical as O2 activation for artificial photosynthesis of hydrogen peroxide (H2O2) via two‐electron oxygen reduction reaction (2e− ORR). However, proton release via water dissociation is frequently hindered because of the sluggish water oxidation reaction (WOR), extremely limiting the efficiency of photocatalytic H2O2 production. To tackle this challenge, carboxyl‐enriched supramolecular polymer (perylene tetracarboxylic acid—PTCA) is elaborately prepared by molecular self‐assembly for overall photosynthesis of H2O2. Interestingly, the interconversion between carboxyl as Brønsted acid and its conjugated base realizes rapid proton circulation. Through this efficient tandem proton transfer process, the spatial effect of photocatalytic reduction and oxidation reaction is greatly enhanced with reduced reaction barrier. This significantly facilitates 2e− photocatalytic ORR to synthesize H2O2 and in the meanwhile promotes 4e− photocatalytic WOR to evolve O2. Consequently, the as‐developed PTCA exhibits a remarkable H2O2 yield of 185.6 μM h−1 in pure water and air atmosphere under visible light illumination. More impressively, an appreciable H2O2 yield of 78.6 μM h−1 can be well maintained in an anaerobic system owing to in situ O2 generation by 4e− photocatalytic WOR. Our study presents a novel concept for artificial photosynthesis of H2O2 via constructing efficient proton transfer pathway to enable rapid proton circulation. [ABSTRACT FROM AUTHOR]

By embedding Na ions into graphitic carbon nitride, the directional migration of photo-generated electrons towards Na sites is achieved, thereby creating additional reaction sites. Moreover, the electron-rich Na sites enhance the adsorption and activation of CO 2. Consequently, the photocatalytic performance is improved to some extent. [Display omitted] The depressed directional separation of photogenerated carriers and weak CO 2 adsorption/activation activity are the main factors hampering the development of artificial photosynthesis. Herein, Na ions are embedded in graphitic carbon nitride (g-C 3 N 4) to achieve directional migration of the photogenerated electrons to Na sites, while the electron-rich Na sites enhance CO 2 adsorption and activation. Na/g-C 3 N 4 (NaCN) shows improved photocatalytic reduction activity of CO 2 to CO and CH 4 , and under simulated sunlight irradiation, the CO yield of NaCN synthesized by embedding Na at 550°C (NaCN-550) is 371.2 μmol g−1 h−1, which is 58.9 times more than that of the monomer g-C 3 N 4. By means of theoretical calculations and experiments including in situ fourier transform infrared spectroscopy, the mechanism is investigated. This strategy which improves carrier separation and reduces the energy barrier at the same time is important to the development of artificial photosynthesis. [ABSTRACT FROM AUTHOR]

A solvent‐free sulfur‐bridge‐eosin‐Y (SBE‐Y) polymeric framework photocatalyst was prepared for the first time through an in situ thermal polymerization route using elemental sulfur (S8) as a bridge. The addition of a sulfur bridge to the polymeric framework structure resulted in an allowance of the harvesting range of eosin‐Y (E‐Y) for solar light. This shows that a wider range of solar light can be used by the bridge material's photocatalytic reactions. In this context, supercharged solar spectrum: enhancing light absorption and hole oxidation with sulfur bridges. This suggests that the excited electrons and holes through solar light can contribute to oxidation–reduction reactions more potently. As a result, the photocatalyst‐enzyme attached artificial photosynthesis system developed using SBE‐Y as a photocatalyst performs exceptionally well, resulting in high 1,4‐NADH regeneration (86.81%), followed by its utilization in the exclusive production of formic acid (210.01 μmol) from CO2 and synthesis of fine chemicals with 99.9% conversion yields. The creation of more effective photocatalytic materials for environmental clean‐up and other applications that depend on the solar light‐driven absorption spectrum of inorganic and organic molecules could be one of the practical ramifications of this research. [ABSTRACT FROM AUTHOR]

In the last few decades, photochemistry has great influence on all type of synthetic processes. While photochemical synthesis is emerging field in inorganic chemistry as it impart various magnificent properties to materials that are used for synthesis of nano-sized materials to giant supramolecular structures. There are many photochemical based synthetic approaches like electron, atom, energy transfer depending upon the need of product where one can switch the pathway. A variety of inorganic compounds have been synthesized like dienes, nitrides, indoles, gold nano-particles and supramolecular structures using photochemical route. Photochemical synthesis has various applications like artificial photosynthesis and fluorophores. [ABSTRACT FROM AUTHOR]

The utilization of solar energy by light conversion processes in both natural and artificial photosynthesis systems has become a pivotal means of sustaining a consistent power supply for our daily lives and production. In general, these reactions rely on the visible spectra region where the sun produces abundant energy according to the black body's emission. Further expanding the adoption of the near-infrared (NIR) spectral region through upconversion has become an intelligent strategy to improve the entire utilization rate of solar energy. In this work, the two-photon upconversion (TPUC) properties were discovered in CsPbBr3 nanoplates (NPs) emitted at 450 nm, and a sub-gap energy level was observed to serve as the center to facilitate the upconversion process. The excitation threshold for TPUC is drastically lower than that for the two-photon absorption, another nonlinear upconversion path that requires strengthened excitation power. Moreover, a significant negative correlation between the excitation threshold for TPUC in the CsPbBr3 NPs and the exciton binding energy was unveiled, which could be attributed to the enhanced quantum confinement effects. Our work paved the way for a feasible way to expand the utilization of the NIR spectral region in light conversion applications. [ABSTRACT FROM AUTHOR]

The carbon dioxide (CO2) conversion to useable compounds remains a great contest to scientists, engineers, and environmentalists with regard to the reverse of the oxidative degradation of organics. This conversion is essential for the development of complementary fuels and raw materials for various industries, which in turn will help in avoiding the drastic increase in tropospheric temperature due to greenhouse effect leading to global warming. The solar energy is the earth's essential power source along with the other various forms of energy for example fossil fuels, hydropower, wind, and biomaterials, etc. The final goal is to establish the artificial photosynthesis, which can be replicated thru various chemical reduction techniques of CO2 by employing appropriate photo-, thermal- and electro-catalysts in order to produce different one carbon atom (C1) and higher carbon atoms containing products. Besides, the utilization of clean and sustainable CO2 towards high-value products is of great interest today due to the recognized environmental worries and subsequent lessening of the fossil fuels utilization load to meet the energy demand of mankind. This way, solar energy can directly and/or indirectly be altered and stored in chemical energy form for industrial as well as societal applications. In this article our endeavor is to summarize the advances in CO2 chemical reduction research area till date especially in free radical-based methods such as electrochemical, photochemical and plasma chemical for the development of carbon species up to two carbon (C2) atoms containing products perceived in the chemical reduction of CO2. The author hopes that this piece of work will be helpful to researchers and readers who are focused on the field of CO2. [ABSTRACT FROM AUTHOR]