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Efficient harvesting of unlimited solar energy and its conversion into valuable chemicals is one of the ultimate goals of scientists. With the ever-increasing concerns about sustainable growth and environmental issues, numerous efforts have been made to develop artificial photosynthetic process for the production of fuels and fine chemicals, thus mimicking natural photosynthesis. Despite the research progress made over the decades, the technology is still in its infancy because of the difficulties in kinetic coupling of whole photocatalytic cycles. Herein, we report a new type of artificial photosynthesis system that can avoid such problems by integrally coupling biocatalytic redox reactions with photocatalytic water splitting. We found that photocatalytic water splitting can be efficiently coupled with biocatalytic redox reactions by using tetracobalt polyoxometalate and Rh-based organometallic compound as hole and electron scavengers, respectively, for photoexcited [Ru(bpy)3]2+. Based on these results, we could successfully photosynthesize a model chiral compound (l-glutamate) using a model redox enzyme (glutamate dehydrogenase) upon in situ photoregeneration of cofactors. [ABSTRACT FROM AUTHOR]

Abstract: We present a versatile route for promoting cell adhesion and viability on various non-wetting surfaces, inspired by mussel adhesion mechanism. The oxidative polymerization of dopamine, a small designer molecule of the DOPA-K motif found in mussels, results in the formation of a poly(dopamine) ad-layer on any material surface. We found that the poly(dopamine) coating can promote cell adhesion on any type of material surfaces including the well-known anti-adhesive substrate, poly(tetrafluoroethylene). According to our results, mammalian cells well adhered and underwent general cell adhesion processes (i.e., attachment to substrate, spreading, and cytoskeleton development) on poly(dopamine)-modified surfaces, while they barely adhered and spread on unmodified non-wetting surfaces. The mussel-inspired surface functionalization strategy is extremely useful because it does not require the time-consuming synthesis of complex linkers and the process is solvent-free and non-toxic. Therefore, it can be a powerful route for converting a variety of bioinert substrates into bioactive ones. [Copyright &y& Elsevier]

Recently discovered evidences suggest that precipitation of Alzheimer's β-amyloid (Aβ) peptide and the toxicity in Alzheimer's disease (AD) are caused by abnormal interactions with neocortical metal ions, especially Zn2+, Cu2+, and Fe3+. While many studies had focused on the role of a "single" metal ion and its interaction with Aβ peptides, such studies involving "multiple" metal ions have hardly been explored. Here, to explore the nature of codeposition of different metals, two or more metal ions along with Aβ were incubated over a solid template prepared by immobilizing Aβ42 oligomers. The influence of Zn2+, Cu2+, and Fe3+ on Aβ aggregation was investigated by two approaches: co-incubation and sequential addition. Our results using ex situ AFM, ThT-induced fluorescence, and FTIR spectroscopy indicated that the co-incubation of Cu2+, Zn2+, and Fe3+ significantly altered the morphology of aggregates. A concentration dependence study with mixed metal ions suggested that Zn2+ was required at much lower concentrations than Cu2+ to yield nonfibrillar amorphous Aβ deposits. In addition, sequential addition of Zn2+ or Cu2+ on fibrillar aggregates formed by Fe3+ demonstrated that Zn2+ and Cu2+ could possibly change the conformation of the aggregates induced by Fe3+. Our findings elucidate the coexistence of multiple metal ions through their interactions with Aβ peptides or its aggregates. [ABSTRACT FROM AUTHOR]

Abstract: The aggregation of soluble β-amyloid (Aβ) peptide into oligomers/fibrils is one of the key pathological features in Alzheimer''s disease (AD). The use of naturally occurring small molecules for inhibiting protein aggregation has recently attracted many interests due to their effectiveness for treating protein folding diseases such as AD, Parkinson''s, Huntington''s disease, and other amyloidosis diseases. α-d-Mannosylglycerate (MG), a natural extremolyte identified in microorganisms growing under extremely high temperatures up to 100°C, had been shown to protect proteins against various stress conditions such as heat, freezing, thawing, and drying. Here, we report the effectiveness of MG on the suppression of Alzheimer''s Aβ aggregation and neurotoxicity to human neuroblastoma cells. According to our study – carried out by using thioflavin-T induced fluorescence, atomic force microscopy, and cell viability assay – MG had significant inhibitory effect against Aβ amyloid formation and could reduce the toxicity of amyloid aggregates to human neuroblastoma cells while MG itself was innocuous to cells. On the other hand, the structural analogs of MG such as α-d-mannosylglyceramide, mannose, methylmannoside, glycerol, showed negligible effect on Aβ aggregate formation. The results suggest that MG could be a potential drug candidate for treating Alzheimer''s disease. [Copyright &y& Elsevier]

[Display omitted] • Open-cell PDMS sponge was produced by water droplet templating method. • The PDMS sponge is prepared without the use of surfactants and toxic additives. • Total preparation time of PDMS sponge was less than 15 min. • The PDMS sponge exhibited outstanding oil-absorbing properties and was reusable. The conventional fabrication methods for porous polymers involve high energy consumption and the use of chemicals and toxic additives, leading to environmental pollution. In the quest for energy-efficient and eco-friendly techniques, we developed a surfactant-free spray-assisted water droplet templating (SWDT) method for fabricating a polydimethylsiloxane (PDMS) sponge with efficient oil-absorbing properties. This method employs a spray atomizer to generate additive-free water droplets and ultraviolet curing to prepare a droplet-templated PDMS sponge, thereby being an environmentally friendly (no use of surfactant), easy (simple procedure and conventional equipment), and efficient (low time and energy consumption) way to fabricate porous structures. The resulting PDMS sponge exhibits high porosity (approximately 80.8 %), high oil absorption capacity (39.0 g/g), and excellent reusability without significant degradation of the structure and capacity. We expect that the SWDT method can contribute to the sustainable development of reusable porous polymer manufacturing because of its low environmental impact. This method holds promise for reusable polymer sorbent which can be utilized in oil spill accidents. [ABSTRACT FROM AUTHOR]

Tin–lead halide perovskites (TLHPs) are promising photoactive materials for photovoltaics (PVs) due to reduced toxicity and broad light absorption. However, their inherent ionic vacancies facilitate inward metal diffusion, accelerating device degradation. Here, efficient, stable TLHP‐based PV and photoelectrochemical (PEC) devices are reported containing a chemically protective cathode interlayer—amine‐functionalized perylene diimide (PDINN). Solution‐processed PDINN effectively extract electrons and suppress inward‐metal diffusion by forming tridentate metal complexes with its nucleophilic sites. The PV device achieved an efficiency of 23.21% (>81% retention after 750 h at 60 °C and >90% retention after 3100 h at 23 ± 4 °C), and the first demonstration of TLHP‐based PEC devices exhibit a record‐high bias‐free solar hydrogen production rate (33.0 mA cm−2; ≈3.42 × 10−6 kg s−1 m−2) when coupled with biomass oxidation, which is ≈1.7‐fold higher than the ultimate target set by the U.S. Department of Energy for one‐sun hydrogen production. These findings demonstrate the potential of TLHPs for efficient, stable photoconversion by the molecular design of the cathode interlayer. [ABSTRACT FROM AUTHOR]

Facile removal of adsorbed gas bubbles from electrode surfaces is crucial to realize efficient and stable energy conversion devices based on electrochemical gas evolution reactions. Conventional studies on bubble removal have limited applicability and scalability due to their reliance on complex and energy/time‐intensive processes. In this study, a simple and versatile method is reported to fabricate large‐area superaerophobic electrodes (up to 100 cm2) for diverse gas evolution reactions using the gel‐like aerophobic surface system (GLASS). GLASS electrodes are readily and uniformly fabricated by simple spin‐coating and cross‐linking of polyallylamine on virtually any kinds of electrodes within 5 min under ambient conditions. Intrinsically hydrophilic gel overlayers with interconnected open pores allow the physical separation of bubble adhesion and catalytic active sites, reducing bubble adhesion strength, and promoting the removal of gas bubbles. As a result, GLASS electrodes exhibit greatly enhanced efficiency and stability for diverse gas evolution reactions, such as hydrogen evolution, hydrazine oxidation, and oxygen evolution reactions. This study provides deeper insights into understanding the effect of the hydrophilic microenvironment on gas evolution reactions and designing practical electrochemical devices. [ABSTRACT FROM AUTHOR]

Under visible light irradiation, the rationally designed catalyst had high photocatalytic activity and stability for H 2 O 2 production without additional photosensitizers, cocatalysts, and even sacrificial electron donors. [Display omitted] Producing hydrogen peroxide (H 2 O 2) from H 2 O and O 2 under visible light irradiation is a promising solar-to-chemical energy conversion technology. Hydrogen peroxide has versatile applications as a green oxidant and liquid energy carrier but has been produced through energy-intensive and complex anthraquinone processes. Herein, we report the rational design of efficient and stable porous organic polymer (POP) containing redox centers, anthraquinone photocatalyst (ANQ-POP) for solar H 2 O 2 production. ANQ-POP is readily synthesized with stable dioxin-linkages via efficient one-pot, transition-metal-free nucleophilic aromatic substitution reactions between 1,2,3,4,5,6,7,8-octafluoro-9,10-anthraquinone (OFANQ) and 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP). Exhibiting a fibrillar morphology, ANQ-POP boasts a high surface area of 380 m2∙g−1 and demonstrates thermal stability. With 10 % ethanol, ANQ-POP yields an H 2 O 2 production rate of 320 μmol g−1 under visible light irradiation. Moreover, ANQ-POP alone can efficiently produce H 2 O 2 without any photosensitizers and cocatalysts. Density functional theory calculations reveal that the quinone groups of the anthraquinone moieties can serve as redox centers for H 2 O 2 production under light irradiation. Furthermore, unlike most conventional photocatalysts, it can produce H 2 O 2 using only water and air by catalyzing both oxygen reduction and evolution reactions under light irradiation. Our findings provide an efficient, eco-friendly pathway for photocatalytic production of H 2 O 2 under mild reaction conditions using a dioxin-derived POP-based photocatalyst. [ABSTRACT FROM AUTHOR]

Recent studies have found that green hydrogen production and biomass utilization technologies can be combined to efficiently produce both hydrogen and value‐added chemicals using biomass as an electron and proton source. However, the majority of them have been limited to proof‐of‐concept demonstrations based on batch systems. Here the authors report the design of modular flow systems for the continuous depolymerization and valorization of lignin and low‐voltage hydrogen production. A redox‐active phosphomolybdic acid is used as a catalyst to depolymerize lignin with the production of aromatic compounds and extraction of electrons for hydrogen production. Individual processes for lignin depolymerization, byproduct separation, and hydrogen production with catalyst reactivation are modularized and integrated to perform the entire process in the serial flow. Consequently, this work enabled a one‐flow process from biomass conversion to hydrogen gas generation under a cyclic loop. In addition, the unique advantages of the fluidic system (i.e., effective mass and heat transfer) substantially improved the yield and efficiency, leading to hydrogen production at a higher current density (20.5 mA cm−2) at a lower voltage (1.5 V) without oxygen evolution. This sustainable eco‐chemical platform envisages scalable co‐production of valuable chemicals and green hydrogen for industrial purposes in an energy‐saving and safe manner. [ABSTRACT FROM AUTHOR]

Microfluidic systems with large surface‐to‐volume ratios and superior light transmission are used to efficiently transfer mass and convert energy, and to enhance photocatalytic reactions. Utilizing the entire solar spectrum for promoting photocatalytic reactions is highly desirable and near‐infrared (NIR) radiation, in particular, has a high transmission efficiency through common polymers and materials used to construct microfluidic devices. Herein, a reliable microfluidic system using bimodal light‐harvesting technique is reported to improve the photocatalytic efficiency of C(sp3)‐H functionalization reactions using coumarin dye (C153) and lanthanide‐doped upconversion nanocrystals (UCNs). Using two light‐harvesting components (C153 and UCNs) in polycarbosilane polymer matrix, a bimodal light‐harvesting microfluidic reactor is realized in which the inner surface of the microfluidic channel is reliably coated with a transparent composite of C153/UCNs to simultaneously downshift visible light and upconvert NIR light. A double‐stacked microfluidic system that successfully enhanced the photocatalytic conversion efficiency of Rose Bengal‐based aza‐Henry photocatalytic reactions by twofold (≈93% conversion). The study provides a design principle of next‐generation microfluidic reactor for a robust photocatalytic organic synthesis. [ABSTRACT FROM AUTHOR]

Removal of gas bubbles from the electrode surface is practically important to maintain the activity of electrochemical gas evolution reactions. Conventionally, most studies have focused on the development of electrocatalysts and paid less attention to the bubble removal issues. Recently, it has been reported that attached gas bubbles can be readily eliminated by imparting extremely gas‐repellent properties (so‐called superaerophobicity) to electrodes via controlling their nano/microstructure. However, this approach is material‐specific and requires harsh and expensive synthetic conditions, causing difficulties in scaling up to large‐area electrodes for commercialization. To address these issues, a universal method to impart superaerophobicity to various electrodes through simple coating with porous polymeric hydrogels without affecting the underlying target substrates is reported. The modification of electrodes with superaerophobic polymeric hydrogel substantially enhances the efficiency of the hydrogen evolution reaction because the hydrogel can facilitate the removal of as‐generated gas bubbles and thereby minimize ohmic and concentration overpotentials. Particularly, electrodes modified with the superaerophobic hydrogel outperform those modified with electrocatalysts at high current densities where more gas bubbles are generated and adhered to. The results provide insights into the design of various electrochemical devices that are based on gas‐involving reactions. [ABSTRACT FROM AUTHOR]

Abstract: Amyloid-β (Aβ) is the major constituent of senile plaques in the brains of Alzheimer''s disease patients. In order to develop an efficient in vitro system for studying the interaction of cells with Aβ aggregates, we have prepared a synthetic amyloid lawn by immobilizing Aβ peptides over a functionalized glass surface and subsequently incubating the template in a fresh Aβ solution. On the top of different types of amyloid lawns (e.g. monomeric, oligomeric, and fibrillar), we cultivated PC12 cells, creating physical contacts between the cells and the lawns. Results indicated that cell viability was differentially affected when grown atop different Aβ lawns while cells were well adhered onto the surface of these Aβ lawns. The mode of cell death by Aβ lawn was confirmed to be apoptotic rather than necrotic, showing that cells undergo suicide by just contact with Aβ lawn. While conventional ‘solution-based’ methods for testing amyloid toxicity suffer from problems such as lot-to-lot variations, continued fibrillation, and heterogeneous population of aggregates, our ‘surface-based’ lawn system is suitable for high-throughput analysis of amyloid toxicity, which may enable high-throughput screening of potential drug candidates for treating amyloid diseases with the goal of reducing the cell death on the lawn. [Copyright &y& Elsevier]

[Display omitted] • Hexagonal rosettes of CM adduct were fabricated as a precursor for g-C 3 N 4. • The confined polymerization of the CM rosettes was performed at 500 °C. • Condensation of CM adduct leads to the formation of hexagonal rosettes of g-C 3 N 4. • A thorough mechanism pathway for the polymerization process was elaborated. • The rosette g-C 3 N 4 showed superb photocatalytic activity for H 2 and H 2 O 2 production. Photocatalytic sustainable fuel production attracted extensive attention because of the urgent need of the society to shift from fossil fuels to solar fuels. Herein, the synthesis of hexagonal rosettes of g-C 3 N 4 with an efficient performance toward hydrogen evolution and hydrogen peroxide production as the two kinds of solar fuels were reported. The hexagonal rosettes of g-C 3 N 4 were simply fabricated via controlled solid-state polymerization of three-dimensional hexagonal rosettes of cyanuric acid-melamine adduct at 500 °C. The hexagonal rosettes of g-C 3 N 4 showed an amorphous nature with an extremely high surface area of 400 m2 g−1. Also, the as-obtained catalyst demonstrated remarkable photocatalytic activity in hydrogen production of 1285 μmol g−1 h−1 and hydrogen peroxide production of 150 μmol g−1 h−1. The mechanism for the polymerization process of the cyanuric acid-melamine (CM) complex to hexagonal rosettes of g-C 3 N 4 was thoroughly described employing electron microscopy tools. This study identified that the CM complex condensation is accomplished via a dehydration process by producing a highly condensed and active structure of g-C 3 N 4 , which is different from the previously reported condensation mechanism of the melamine and its derivatives performed through a deamination process. [ABSTRACT FROM AUTHOR]

The charge separation efficiency of water oxidation photoanodes is modulated by depositing polyelectrolyte multilayers on their surface using layer‐by‐layer (LbL) assembly. The deposition of the polyelectrolyte multilayers of cationic poly(diallyldimethylammonium chloride) and anionic poly(styrene sulfonate) induces the formation of interfacial dipole layers on the surface of Fe2O3 and TiO2 photoanodes. The charge separation efficiency is modulated by tuning their magnitude and direction, which in turn can be achieved by controlling the number of bilayers and type of terminal polyelectrolytes, respectively. Specifically, the multilayers terminated with anionic poly(styrene sulfonate) exhibit a higher charge separation efficiency than those with cationic counterparts. Furthermore, the deposition of water oxidation molecular catalysts on top of interfacial dipole layers enables more efficient photoelectrochemical water oxidation. The approach exploiting the polyelectrolyte multilayers for improving the charge separation efficiency is effective regardless of pH and types of photoelectrodes. Considering the versatility of the LbL assembly, it is anticipated that this study will provide insights for the design and fabrication of efficient photoelectrodes. [ABSTRACT FROM AUTHOR]

Solar‐to‐chemical energy conversion, or so‐called artificial photosynthesis, is a promising technology enabling sustainable production and use of various chemical compounds such as H2, CO, CH4, HCOOH, CH3OH, and NH3. For practical applications, it is necessary to improve the interfacial properties of light‐harvesting semiconductors through modification with proper electrocatalysts, by trying to overcome their intrinsic limitations such as rapid recombination, sluggish reaction kinetics, and photocorrosion. Compared to their heterogeneous counterparts, molecular electrocatalysts have a higher catalytic activity and more flexibility in their design/synthesis and integration with semiconducting materials. In this article, we review recent efforts on the tailored assembly of molecular electrocatalysts to address the above issues for artificial photosynthesis, especially those for oxygen evolution reactions on semiconductor photoelectrodes for photoelectrochemical water oxidation. One can expect that the strategies and methods developed for the tailored assembly and integration of molecular electrocatalysts on water oxidation photoanodes can provide insights for the design and fabrication of various forms of photosynthetic devices due to the similarity between their underlying principles. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • POMs were converted to CoWO 4 nanoparticles by annealing. • POM-derived a-CoWO 4 exhibited excellent catalytic activity for water oxidation. • Its catalytic activity was closely related to the formation of oxygen vacancies. • It was readily integrated on a desired surface by adsorption and annealing of POMs. • This enabled simple preparation of efficient (photo)anodes for water oxidation. Abstract Highly efficient water-oxidation catalysts (WOCs) were readily prepared through the simple heat treatment of cobalt-containing polyoxometalate [Co 4 (H 2 O) 2 (PW 9 O 34) 2 ]10− (POM). The annealing of soluble POM molecules at high temperatures in air led to the formation of insoluble nanoparticles, of which the crystal structure and catalytic activity can be controlled by the annealing temperature. POMs were converted to amorphous and crystalline CoWO 4 nanoparticles when annealed at 400 and 500 °C, respectively. Interestingly, amorphous CoWO 4 nanoparticles exhibited excellent catalytic activity near the neutral pH of pH 8.0, making them superior to both pristine POM and POM-derived crystalline CoWO 4 nanoparticles. X-ray absorption and photoelectron spectroscopies combined with density functional theory (DFT) calculations revealed that their outstanding performance was resulted from the generation of large amounts of oxygen vacancies upon annealing, leading to the optimum distance between the nearest Co ions for the Langmuir-Hinshelwood (LH) mechanism. Based on these findings, we could readily immobilize CoWO 4 -based WOCs on the surfaces of various electrodes for efficient electrochemical and photoelectrochemical water oxidation through the annealing of POMs pre-adsorbed onto the desired electrode surface. This study may provide insights not only for the synthesis of efficient electrocatalysts derived from POMs but also for their immobilization onto the desired electrode surface for practical applications. [ABSTRACT FROM AUTHOR]

We report a fully solution processable bias-free photoelectrochemical (PEC) cell for overall solar water splitting using a Cu2O photocathode and a BiVO4 photoanode. They were modified with catalytic multilayers (CMs) for hydrogen and oxygen evolution reactions (HER and OER), respectively, using simple and versatile layer-by-layer (LBL) assembly. The deposition of the respective CMs composed of cationic polyelectrolyte and anionic molecular polyoxometalate (POM) electrocatalysts resulted in remarkably improved performance in terms of both photocatalytic activity and stability. Detailed PEC analysis revealed that the CMs not only facilitated (1) charge transport to and (2) catalytic charge transfer at the photoelectrode/electrolyte interface, but also suppressed the deactivation of photoelectrodes, especially a labile Cu2O photocathode, by the formation of a protective coating layer. As a result, we could successfully fabricate an efficient and stable PEC cell for unassisted solar water splitting without the use of toxic/hazardous chemicals and energetic processes, which have been inevitably employed. We believe that this study provides a simple and versatile platform for the design and fabrication of various forms of electrochemical PEC devices in an environmentally friendly manner. [ABSTRACT FROM AUTHOR]

Porous hydrogels facilitate the removal of adsorbed hydrogen gas bubbles during water electrolysis and allow more efficient hydrogen production. Superaerophobic Polyethyleneimine Hydrogels for Improving Electrochemical Hydrogen Production by Promoting Bubble Detachment (Adv. Keywords: hydrogels; hydrogen evolution reaction; polyethyleneimine; superaerophobicity; three-phase interface EN hydrogels hydrogen evolution reaction polyethyleneimine superaerophobicity three-phase interface 1 1 1 08/08/22 20220804 NES 220804 B Electrochemical Hydrogen Production b In article number 2201452, Dasom Jeon, Jungki Ryu, and co-workers report that a hydrogel coating can improve the performance of electrodes for electrochemical hydrogen production even without additional catalysts. [Extracted from the article]

Graphene-wrapped metal oxide hybrid materials are synthesized through inspiration from natural CO2 mineralization. We created hierarchical, nanostructured graphene/metal oxide by converting a CO2-mineralized graphene oxide/CaCO3 precursor to metal-based minerals such as graphene-wrapped CuO hybrid materials, which highly enhanced the stability and recyclability of the CuO anode for Li ion batteries. The synthesis of graphene-wrapped metal oxide and its application to Li ion battery electrodes suggest a new possibility for hybridizing graphene and metal oxide nanoparticles using the inspiration of natural mineralization. [ABSTRACT FROM AUTHOR]

Abstract: A self-assembled peptide hydrogel consisting of Fmoc-diphenylalanine has been employed as a biosensing platform through the encapsulation of enzyme bioreceptors (e.g., glucose oxidase or horseradish peroxidase) and fluorescent reporters (e.g., CdTe and CdSe quantum dots). Enzymes and quantum dots (QDs) were physically immobilized within the hydrogel matrix in situ in a single step by simply mixing aqueous solution containing QDs and enzymes with monomeric peptide (Fmoc-diphenylalanine) solution. By using atomic force microscopy and scanning transmission electron microscopy, we observed that the self-assembled peptide hydrogel had a three-dimensional network of nanofibers (with a diameter of approximately 70–90nm) that physically hybridized with QDs and encapsulated enzyme bioreceptors with a minimal leakage. We successfully applied the peptide hydrogel to the detection of analytes such as glucose and toxic phenolic compounds by using a photoluminescence quenching of the hybridized QDs. The Michaelis–Menten constant (K M) of the photoluminescent peptide hydrogel was found to be 3.12mM (GOx for glucose) and 0.82mM (HRP for hydroquinone), respectively, which were much lower than those of conventional gel materials. These results suggest that the peptide hydrogel is an alternative optical biosensing platform with practical advantages such as simple fabrication via self-assembly, efficient diffusion of target analytes, and high encapsulation efficiencies for fluorescent reporters and bioreceptors. [ABSTRACT FROM AUTHOR]

Charge Separation Efficiency: Modulating Charge Separation Efficiency of Water Oxidation Photoanodes with Polyelectrolyte-Assembled Interfacial Dipole Layers (Adv. Funct. Keywords: charge separation; interfacial dipole; layer-by-layer assembly; photoelectrodes; polyelectrolyte multilayers Charge separation, interfacial dipole, layer-by-layer assembly, photoelectrodes, polyelectrolyte multilayers. [Extracted from the article]

Solar-to-Chemical Energy Conversion: Modular Layer-by-Layer Assembly of Polyelectrolytes, Nanoparticles, and Molecular Catalysts into Solar-to-Chemical Energy Conversion Devices (Adv. Funct. In article number 1906407, Joonseok Lee, Jiseok Lee, Jungki Ryu, and co-workers suggest the fabrication of solar-to-chemical energy conversion devices using a layer-by-layer assembly method. Rational and precise assembly of plasmonic and upconversion nanoparticles, polyelectrolytes, and molecular catalysts enables more efficient light-harvesting, surface passivation, and catalysis, respectively, for solar water oxidation. [Extracted from the article]

The design and fabrication of solar‐to‐chemical energy conversion devices are enabled through interweaving multiple components with various morphologies and unique functions using a versatile layer‐by‐layer assembly method. Cationic and anionic polyelectrolytes are used as an electrostatic adhesive to assemble the following functional materials: plasmonic Ag nanoparticles for improved light harvesting, upconversion nanoparticles for utilization of near‐infrared light, and polyoxometalate water oxidation catalysts for enhanced catalytic activity. Polyelectrolytes also have an additional function of passivating the surface recombination centers of the underlying photoelectrode. These functional components are precisely assembled on a model photoanode (e.g., Fe2O3 and BiVO4) in a desired order and various combinations without degradation of their intrinsic properties. As a result, the performance of water oxidation photoanodes is synergistically enhanced. This study can enable the design and fabrication of novel solar‐to‐chemical energy conversion devices. [ABSTRACT FROM AUTHOR]

M13 bacteriophages can provide a versatile platform for nanobiotechnology because of their unique biological and physicochemical properties. Polypeptides on their surfaces can be finely tuned on demand through genetic engineering, enabling tailored assembly of multiple functional components through specific interactions. Their versatility has been demonstrated by synthesizing various unprecedented hybrid materials for energy storage, biosensing, and catalysis. Here we select a specific type of genetically engineered M13 bacteriophage (DSPH) to investigate the origin of interactions. The interaction forces between the phage-coated surface and five different functionalized self-assembled monolayers are directly measured using a surface forces apparatus. We confirm that the phages have strong adhesion energies in acidic environments due to π-π stacking and hydrophobic interactions, while hydrogen bonding interactions remain relatively weak. These results provide quantitative and qualitative information of the molecular interaction mechanisms of DSPH phages, which can be utilized as a database of the bacteriophage interactions. Bacteriophages are widely used in nanotechnology. Here the specific intermolecular forces controlling interactions between a bacteriophage peptide and several self-assembled monolayers are probed and shown to depend on pi-pi stacking and hydrophobic interactions. [ABSTRACT FROM AUTHOR]