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Clarifying the reaction pathways at the solid–water interface and in bulk water solution is of great significance for the design of heterogeneous catalysts for selective oxidation of organic pollutants. However, achieving this goal is daunting because of the intricate interfacial reactions at the catalyst surface. Herein, we unravel the origin of the organic oxidation reactions with metal oxide catalysts, revealing that the radical-based advanced oxidation processes (AOPs) prevail in bulk water but not on the solid catalyst surfaces. We show that such differing reaction pathways widely exist in various chemical oxidation (e.g., high-valent Mn 3+ and MnO X ) and Fenton and Fenton-like catalytic oxidation (e.g., Fe 2+ and FeOCl catalyzing H 2 O 2 , Co 2+ and Co 3 O 4 catalyzing persulfate) systems. Compared with the radical-based degradation and polymerization pathways of one-electron indirect AOP in homogeneous reactions, the heterogeneous catalysts provide unique surface properties to trigger surface-dependent coupling and polymerization pathways of a two-electron direct oxidative transfer process. These findings provide a fundamental understanding of catalytic organic oxidation processes at the solid–water interface, which could guide the design of heterogeneous nanocatalysts.

Using renewable biomass to replace fossil resources for producing low-carbon-footprint but high-value chemicals is a sustainable approach to pursue a carbon-neutral society. Herein, a boron nitrogen doped carbon (BNC) confined Pd single atom catalyst (Pd SAs/BNC) is synthesized and used as a robust catalyst toward the reductive amination reaction to produce low-carbon-footprint amines from renewable biomass. Because of the finely tuned electron structure, the as-synthesized single atom catalyst delivers an ultrahigh turn-over frequency value (max. 1368 h− 1) in the reductive amination of aldehydes/ketones and demonstrates a great conversion capacity for various aldehyde/ketone and amine/nitro-compound substrates. Extensive characterizations and density functional theory calculations show that the highly polar metal-N site formed between the central Pd single atom and its neighboring N and B atoms favors hydrogen activation from the donor (reductants) and hydrogen transformation to the receptor (C = O group), resulting in a great selectivity. This system could be further extended to directly produce various aromatic and furonic amines from renewable lignocellulosic biomass, and their greenhouse gas emission potentials are negative compared to those of fossil-fuel resource-based amines. This work offers a highly efficient and sustainable approach to construct C-N bonds for the production of numerous amines from carbon-neutral biomass resources.

Photosynthesis of hydrogen peroxide (H 2 O 2 ) by selective oxygen reduction is a green and cost-effective alternative to the energy-intensive anthraquinone process. Although inexpensive polymeric graphitic carbon nitride (g-C 3 N 4 ) exhibits the ability to produce H 2 O 2 , its disordered and amorphous structure leads to a high recombination rate of photogenerated carriers and hinders charge transfer between layers. Herein, we predict that stacked polymeric g-C 3 N 4 with ion intercalation (K + and I – ) can improve carrier separation and transfer by multiscale computational simulations. The electronic structures of g-C 3 N 4 were tailored and modified by intercalating K + and I – into the layer-by-layer structures. Guided by the computational predictions, we achieved efficient solar-driven H 2 O 2 production by employing this facile and ion-intercalated crystalline g-C 3 N 4 . An H 2 O 2 production rate of 13.1 mM g −1 h −1 and an apparent quantum yield of 23.6% at 400 nm were obtained. The synergistic effects of crystallinity regulation and dual interstitial doping engineering triggered the formation of new light absorption centers, the establishment of rapid charge diffusion channels, and the enhancement of two-electron oxygen reduction characteristics. This work sheds light on the dual tuning of crystallinity and electronic structure and broadens the design principles of organic-conjugated polymer photocatalysts for environmental remediation and energy conservation.

The biogeochemical cycle of iron is of great importance to living organisms on Earth, and dissimilatory metal-reducing bacteria (DMRB) with the capability of reducing hematite (α-Fe2O3) by outer-membrane (OM) cytochromes play a great role in the iron cycle. However, the dynamic binding of cytochromes to α-Fe2O3 at the molecular level and the resulting impact on the photon-to-electron conversion of α-Fe2O3 for the iron cycle are not fully understood. To address these issues, two-dimensional IR correlation analysis coupled with molecular dynamics (MD) simulations was conducted for an OmcA-Fe2O3 system as OmcA bonds stronger with hematite in a typical DMRB,Shewanella. The photoelectric response of α-Fe2O3 with the OmcA coating was evaluated at three different potentials. Specifically, the binding groups from OmcA to α-Fe2O3 were in the sequence of carboxyl groups, amide II, and amide I. Further MD analysis reveals that both electrostatic interactions and hydrogen bonds played essential roles in the binding process, leading to the structural changes of OmcA to facilitate iron reduction. Moreover, the OmcA coating could store the photogenerated electrons from α-Fe2O3 like a capacitor and utilize the stored electrons for α-Fe2O3 reduction in dark and anoxic environments, further driving the biogeochemical cycle of iron. These investigations give the dynamic information on the OM protein/hematite interaction and provide fundamental insights into the biogeochemical cycle of iron by taking the photon-induced redox chemistry of iron oxide into consideration.

Summary Plasmon-induced charge transfer has drawn considerable interests and spurred rapid developments of photovoltaics and photocatalysis. Various plasmonic metal/transition metal dichalcogenide (TMD) heterostructures have been developed to promote charge separation. For plasmon-induced catalysis, the transformation of TMDs is rare, and the erosion of TMDs has not yet been reported. Here, we report the etching of two-dimensional TMDs by planar surface plasmon polaritons (SPPs). We found that SPPs can etch various TMDs into desired layers and lateral size through controlling the light power and incident direction. In aqueous media, the strong plasmonic coupling at Au/MoS2 interface generates holes in the valence band of MoS2 that can weaken its interlayer interaction. As a synergistic effect, the plasmonic hot electrons produce oxidizing H2O2 to dissolve MoS2 from the top layers. Our results provide a new perspective for understanding the plasmonic coupling at metal-TMD interfaces and a reliable route toward fabricating well-defined TMDs.

Cadmium ion (Cd2+) is a common environmental pollutant with high biotoxicity. Interestingly, the Cd2+ biotoxicity can be alleviated by the coexisting selenite (SeO32-), which induces the formation of cadmium selenide-rich nanoparticles (CdSe NPs) under the function of thiol-capping peptides. However, the detailed biochemical mechanisms by which Cd and Se are synergistically transformed into CdSe NPs in living organisms remain unclear so far. Here, we shed light on the molecular basis of such biotransformation processes in Caenorhabditis elegans by focusing on the roles of several key thiol-capping peptides. By monitoring the compositional and structural changes of the Cd and Se species and the genetic-level responses of nematodes, we revealed the specific roles of glutathione (GSH) and phytochelatins (PCs) in mediating the CdSe NP formation. With the aid of in vitro bioassembly assay and density functional theory calculations, the detailed Cd-Se interaction pathways were further deciphered: the ingested Cd binds predominantly to GSH and PCs in sequence, then further interacts with selenocysteine to form tetrahedral-structured PC2-Cd2-Sec2 complex, and ultimately grows into CdSe NPs. This work provides molecular-level insights into the Cd-Se interaction in C. elegans and lays a basis for controlling the ecological and health risks of heavy metals in polluted environment.

Single-atom catalysts have emerged as an efficient oxidant activator for eliminating organic pollutants in Fenton-like systems. However, the complex preparation, single active site, lack of understanding of the fundamental mechanism, and harsh pH conditions currently limit their practical applications. In this work, single-atom iron anchored nitrogen-rich g-C

Graphitic carbon nitride (gCN) has attracted increasing interest in photocatalysis because of its visible-light-responsive ability, environment-friendliness, low cost and ease of large-scale production. However, its practical application is restricted by its insufficient light absorption, relatively small surface area and low charge separation efficiency. In this work, a post-P-doped gCN nanosheet (gCN-P (post)) with a controllable morphology was successfully synthesized and highly-active P sites were introduced by C/P substitution. The formed porous nanosheet structure greatly increased the specific surface area and exposed more active sites to favor the photocatalytic reaction. gCN-P (post) exhibited excellent visible light photoactivity toward bisphenol A (BPA) degradation with a much higher reaction rate than pristine gCN and other P-doped g-C3N4 composites. Doping P resulted in a narrowed band gap of gCN with enhanced light-harvesting and improved reduction capacity of electrons, which facilitated the reduction of molecular oxygen and the formation of more high-powered oxidative species. The post-P doping could maintain the morphology of gCN nanosheets with a high yield and simultaneously optimize the electronic orbital distribution of the triazine ring. The high BPA mineralization efficiency and preferable photostability capacity further confirmed its application potential. This work provides a promising approach for efficient water and wastewater treatment with rationally designed visible-light-responsive photocatalysts.

Nitarsone, the extensively used organoarsenical in poultry production has resulted in the elevated level of arsenic in aquatic environments, further influencing the arsenic cycling and increasing t...

Rechargeable batteries are promising platforms for sustainable development of energy conversion and storage technologies. Highly efficient multifunctional electrodes based on bimetallic sulfides for rechargeable batteries are extremely desirable but still challenging to tailor with controllable phase and structure. Here, we report a colloidal strategy to fabricate FeCo-based bimetallic sulfides on reduced graphene oxide (rGO), which are expected to display highly efficient oxygen electrocatalysis and sodium storage performances. Specifically, as-screened FeCo8S8 nanosheets (NSs) on rGO originating from suitable tailoring of the Co9S8 matrix with Fe at the atomic level exhibited a very low potential difference (0.77 V) at 10 mA cm-2 and negligible voltage loss after 200 cycles as an air electrode for Zn-air batteries. For Na-ion batteries, FeCo8S8 NS/rGO demonstrated a superior high-rate capability (188 mAh g-1 at 20 A g-1) with long-term cycling stability. The bifunctional electrocatalytic property and sodium storage performance are attributed to not only the synergistic effect of Fe/Co but also the optimized catalytic activity and ion transport ability by the in situ rGO hybrid. This work demonstrates the potential applications of FeCo-based bimetallic sulfides as efficient electrode materials for both rechargeable Zn-air and Na-ion batteries.

Type 1 copper (T1Cu) proteins play important roles in electron transfer in biology, largely due to the unique structure of the T1Cu center, which is reflected by its spectroscopic properties. Previous reports have suggested a correlation between a high ratio of electronic absorbance at ∼450 nm to that at ∼600 nm (

Nanoparticle-based fluorescent probes, typically fabricated by a chemical synthesis route, have been widely used for monitoring trace heavy metals in environments. However, the high-cost and complicated, aggressive fabrication processes restrict their widespread application. In this work, we report the first use of biogenic quantum dots (Bio-QDs) as a highly sensitive, low-cost fluorescent probe for label-free detection of mercury ions (Hg

We have performed sound velocity and unit cell volume measurements of three synthetic, ultrafine micro/nanocrystalline grossular samples up to 50 GPa using Brillouin spectroscopy and synchrotron X-ray diffraction. The samples are characterized by average grain sizes of 90 nm, 93 nm and 179 nm (hereinafter referred to as samples Gr90, Gr93, and Gr179, respectively). The experimentally determined sound velocities and elastic properties of Gr179 sample are comparable with previous measurements, but slightly higher than those of Gr90 and Gr93 under ambient conditions. However, the differences diminish with increasing pressure, and the velocity crossover eventually takes place at approximately 20–30 GPa. The X-ray diffraction peaks of the ultrafine micro/nanocrystalline grossular samples significantly broaden between 15–40 GPa, especially for Gr179. The velocity or elasticity crossover observed at pressures over 30 GPa might be explained by different grain size reduction and/or inhomogeneous strain within the individual grains for the three grossular samples, which is supported by both the pressure-induced peak broadening observed in the X-ray diffraction experiments and transmission electron microscopy observations. The elastic behavior of ultrafine micro/nanocrystalline silicates, in this case, grossular, is both grain size and pressure dependent.

The exposed active sites of semiconductor catalysts are essential to the photocatalytic energy conversion efficiency. However, it is difficult to directly observe such active sites and understand the photogenerated electron/hole pairs' dynamics on a single catalyst particle. Here, we applied a quasi-total internal reflection fluorescence microscopy and laser-scanning confocal microscopy to identify the photocatalytic active sites at a single-molecule level and visualized the photogenerated hole-electron pair dynamics on a single TiO2 particle, the most widely used photocatalyst. The experimental results and density functional theory calculations reveal that holes and electrons tend to reach and react at the same surface sites, i.e., crystal edge/corner, within a single anatase TiO2 particle owing to the highly exposed (001) and (101) facets. The observation provides solid proof for the existence of the surface junction "edge or corner" on single TiO2 particles. These findings also offer insights into the nature of the photocatalytic active sites and imply an activity-based strategy for rationally engineering catalysts for improved photocatalysis, which can be also applied for other catalytic materials.

The unique properties of ionic liquids make them attractive for a wide range of industrial applications, which makes it easy to be released into the environment and cause water or soil pollution. Phytoremediation of organic contaminants is a safe and important process for removing persistent pollutants from the environment. However, due to they are very chemically stable and potentially toxic to plants, whether they can be removed, assimilated and metabolized by plants remains unknown during phytoremediation process. In this study, ryegrass, Lolium perenne L., was used for imidazolium ionic liquid (1-butyl-3-methylimidazolium bromide, [C4mim]+) removal from water. The results show that [C4mim]+ could be taken up, accumulated and metabolized by plants in vivo with a high removal efficiency. Most of the [C4mim]+ was accumulated in the root tissue, with the root concentration fraction factors ranging from 4.9 to 51.5. Two hydroxylated metabolites 1-(4-hydroxybutyl)-3-methylimidazolium, and 1-(n-butyl)-3-(hydroxymethyl)-imidazolium, and two secondary metabolites were detected in the ryegrass after [C4mim]+ uptake. The metabolic mechanism was clarified using density functional theory calculations. Furthermore, [C4mim]+ at a high concentration was found to be high toxic to inhibit the growth of ryegrass markedly. In response, some oxidative stress was observed in the metabolic process, as indicated by increasing of catalase, super dismutase and peroxidase activities. Our results suggested that phytoremediation was an efficient technique for ionic liquids treatment from water.

Biosynthesis offers opportunities for cost-effective and sustainable production of semiconductor quantum dots (QDs), but is currently restricted by poor controllability on the synthesis process, resulting from limited knowledge on the assembly mechanisms and the lack of effective control strategies. In this work, we provide molecular-level insights into the formation mechanism of biogenic QDs (Bio-QDs) and its connection with the cellular substrate metabolism in Escherichia coli. Strengthening the substrate metabolism for producing more reducing power was found to stimulate the production of several reduced thiol-containing proteins (including glutaredoxin and thioredoxin) that play key roles in Bio-QDs assembly. This effectively diverted the transformation route of the selenium (Se) and cadmium (Cd) metabolic from Cd3(PO4)2 formation to CdSxSe1–x QDs assembly, yielding fine-sized (2.0 ± 0.4 nm), high-quality Bio-QDs with quantum yield (5.2%) and fluorescence lifetime (99.19 ns) far exceeding the existing...

Author(s): Iwai, Masakazu; Chen, Jie-Jie; Park, Soomin; Yoneda, Yusuke; Schmid, Eva; Fletcher, Daniel; Fleming, Graham; Niyogi, Krishna | Abstract: Understanding photosynthetic light harvesting requires knowledge of the molecular mechanisms that dissipate excess energy in thylakoids. However, it remains unclear how the physical environment of light-harvesting complex II (LHCII) influences the process of chlorophyll de-excitation. Here, we demonstrate that protein-protein interactions between LHCIIs affect the optical properties of LHCII and thus influence the total energy budget. Aggregation of LHCII in the dark altered its absorption properties, independent of the amount of prior light exposure. We also revisited the triplet excited state involved in light-induced fluorescence quenching and found another relaxation pathway involving emission in the green region, which might be related to triplet excited energy transfer to neighboring carotenoids and annihilation processes that result in photoluminescence. LHCII- containing liposomes with different protein densities exhibited altered fluorescence and scattering properties. Our results suggest that macromolecular reorganization affects overall optical properties, which need to be addressed to compare the level of energy dissipation.

The construction of enzyme-inspired artificial catalysts with enzyme-like active sites and microenvironment remains a great challenge. Herein, we report a single-atomic-site Co catalyst supported by carbon doped boron nitride (BCN) with locally polarized B–N bonds (Co SAs/BCN) to simulate the reductive dehalogenases. Density functional theory analysis suggests that the BCN supports, featured with ionic characteristics, provide additional electric field effect compared with graphitic carbon or N-doped carbon (CN), which could facilitate the adsorption of polarized organochlorides. Consistent with the theoretical results, the Co SAs/BCN catalyst delivers a high activity with nearly complete dechlorination (~98%) at a potential of −0.9 V versus Ag/AgCl for chloramphenicol (CAP), showing that the rate constant (k) contributed by unit mass of metal (k/ratio) is 4 and 19 times more active than those of the Co SAs/CN and state-of-the-art Pd/C catalyst, respectively. We show that Co single atoms coupled with BCN host exhibit high stability and selectivity in CAP dechlorination and suppress the competing hydrogen evolution reaction, endowing the Co SAs/BCN as a candidate for sustainable conversion of organic chloride., Bridging the biocatalytic repertoire and the effective environmental remediation remains a great challenge. Here, inspired by the dehalogenases, the authors designed a single atom Co catalyst on carbon doped boron nitride that exhibits high stability and selectivity in dechlorination.

The utilization of solar energy for hydrogen peroxide (H2O2) production using graphitic carbon nitride (g-C3N4) under visible light irradiation has attracted increasing interests due to its high efficiency and cost-effectiveness. However, this process is still limited by slow charge carrier migration. In this work, continuous regulation of band structure inside g-C3N4 is obtained by defect engineering through gradient calcination. The H2O2 production rate (4980 μmol g−1 h−1) of nitrogen-defective g-C3N4 is 18 times higher than that of pristine g-C3N4. The π*C N-C signals in X-ray absorption near-edge structure spectrum decline, indicating an increased N-defects. The N-defects with the electronic vacancies in the heptazine intensifies its light-harvesting on g-C3N4 and also improve the selectivity of 2-electron O2 reduction. A quantitative structure-activity relationship between N-defects and band structure is unveiled. This work offers an accessible strategy to design photocatalysts with desirable defect structures for energy conservation.

Various photocatalysts have been fabricated and tested for the treatment of water and wastewater. As visible-light-driven photocatalysts, bismuth oxybromide nanomaterials have weak responses to visible light and low activities of using photogenerated h+ to produce hydroxyl radicals ( OH), both of which are limited by their band structures. Thus, modification of bismuth oxybromide to form an optimized band structure is essential to enhance its photocatalytic activity for environmental applications. In this work, an oxygen-rich bismuth oxybromide nanomaterial, Bi24O31Br10 nanobelt, was fabricated using a solvothermal method, which possessed a narrower band gap and a more positive position of valance band top. As a result, this catalyst exhibited a strong response to visible light and produced large quantities of OH directly via its photogenerated h+, which contributed to the outstanding performance of photocatalysis, as evidenced by the experimental results and density functional theoretical (DFT) calculations. Under visible light irradiation, the Bi24O31Br10 nanobelt exhibited a substantially enhanced photocatalytic efficiency for the degradation of bisphenol A compared to those of Bi24O31Br10 and BiOBr nanosheets. Moreover, this catalyst could resist most interfering ions and was able to treat two types of actual industrial wastewaters efficiently. This work elucidates a new approach to modify photocatalysts and is helpful to expand practical applications of photocatalytic technologies for water and wastewater treatment.

Antibiotics residuals in the environments receive wide concerns due to the high risk of generating antibiotic resistance. Natural organic matters (NOM) existed in the environments are considered to have the capacity of binding with organic contaminants, consequently influencing their speciation and transformation in the natural environments. To assess the migration of antibiotics in the environments, it is crucial to understand the binding mechanisms between NOM and antibiotics, which is still unclear due to the limit of available research methods. In this study, the interaction between fulvic acids (FA), one of the main components of NOM, and sulfamethazine (SMZ) was characterized by nuclear magnetic resonance (NMR) combined with surface plasmon resonance (SPR) and isothermal titration calorimetry (ITC) technology. The parameters related to kinetics and thermodynamics of the interaction were determined, and the possible mechanisms driving the interaction were also proposed. In addition, density functional theory (DFT) was used to predict the binding mode between FA and SMZ to reveal the interaction mechanism. Results indicate that FA can effectively bound with SMZ to form a stable complex with a binding constant at the level of 103 L/mol. The kinetic parameters including association and dissociation constants were 29.4 L/mol/s and 6.64 × 10−3 1/s, respectively. Hydrophobic interaction might play significant roles in the binding interaction with ancillary contribution of π-π conjunction arising from the aromatic rings stacking of FA and SMZ.

The catalytic properties of ultrafine metal nanoparticles (NPs) are usually limited by their dispersion of NPs; support is thus needed for ultrafine metal NPs. However, single-dimensional supports ...

A bioelectrochemical system (BES) allows direct electricity production from wastes, but its low-power density, which is mainly associated with its poor anodic performance, limits its practical applications. Here, the anodic performance of a BES can be significantly improved by electrodepositing vitamin B2 (VB2) onto a graphene [reduced graphene oxide (rGO)]-modified glassy carbon electrode (VB2/rGO/GC) with Geobacter sulfurreducens as the model microorganisms. The VB2/rGO/GC electrode results in 200% higher electrochemical activity than a bare GC anode. Additionally, in microbial electrolysis cells, the current density of this composite electrode peaks at ∼210 μA cm–2 after 118 h and is maintained for 113 h. An electrochemical analysis coupled with molecular simulations reveals that using VB2 as a linker between the electrochemically active protein of this model strain and the rGO surface accelerates the electron transfer, which further improves the bioelectricity generation and favors the long-term stabi...

A microbial fuel cell (MFC) is able to convert waste energy into electricity, and its performance is mainly constrained by extracellular electron transfer (EET) at biological/inorganic interfaces. In this work, the interaction process between the microbe’s outer membrane cytochrome (OmcA) and graphene oxide (GO) is investigated in vitro to elucidate the EET mechanism in the MFC. The feasibility of the electron transfer from the purified OmcA to GO is examined by protein film voltammetry tests. Stopped flow analysis demonstrates that the EET kinetic process obeys the Michaelis–Menten equation and exhibits the characteristics of enzyme catalysis. The structural changes of OmcA/GO monitored by a circular dichroism spectroscopy combined with infrared spectroscopy techniques indicate that the formation of a hydrogen bond between the −NH2 group of the residues and the −COOH/–OH group of GO shortens the electron-transfer distance to mitigate the energy barrier. These results help to understand the EET mechanism ...

Bismuth oxychloride (BiOCl) is a typical UV-light-sensitive photocatalyst with a unique layered structure, but exhibits no response towards visible light. This is a main limitation for its practical applications in photocatalytic degradation of pollutants. Among various methods to expand the light absorption region, doping modification is an efficient approach because it can tailor the band structure by forming a doping energy level without changing the layered structure substantially. In this case, the static electric field in the BiOCl crystal can be retained. Since cobalt (Co) exhibits good electrochemical properties, it is an ideal element for doping modification to expand the light absorption region and enhance the charge separation efficiency of BiOCl. In this work, Co-doped BiOCl nanosheets were prepared using a simple hydrothermal route. The doped Co expanded the light absorption region and enhanced the charge separation efficiency by forming a doping energy level in the band gap of BiOCl. As a result, the Co-BiOCl nanosheets exhibited an outstanding photocatalytic performance in degrading bisphenol A (BPA) under visible light irradiation with a degradation rate of 3.5 times higher than that of BiOCl. On the basis of the experimental results and density functional theory calculations, the mechanism of visible-light-driven catalytic BPA degradation by the Co-BiOCl nanosheets was elucidated. Therefore, the feasibility of Co-doping modification for BiOCl was confirmed, and a novel and efficient strategy was provided for the design and synthesis of high-performance photocatalysts.

Metal oxide semiconductors with surface homojunctions characteristic of continuous band bending and well-defined epitaxial interfaces show amazing potential for photocatalytic applications. Herein, a new concept of facet junctions is proposed and validated according to the synergy between the co-exposed crystal facets of shape-tailored anatase TiO2 single crystals. By considering the atomic and electronic interactions between the co-exposed facets, our density functional theory calculations reveal the existence of type-II band alignment between the co-exposed {001} and {101} facets. This band alignment results in in situ construction of a facet junction to allow built-in facet-mediated carrier transfer. The self-constructed {101}/{001} facet junction, due to the effective carrier separation between different exposed facets, exhibits a significantly enhanced quantum efficiency and catalytic performance in photochemical hydrogen generation compared to TiO2 poly-crystals. These findings open a new horizon of facet junction-engineered nano-catalysts for more robust and efficient energy and environmental applications.

Precise modulation of local structure will improve the catalytic performance for single-site catalysts (SSCs), by taming electronic structure of supported metals and impacting the adsorption energy of reaction intermediates. In order to modify and strengthen the metal-support interaction, a controllable drilling process induced by atomic Cu1Ox is presented for fabrication of accessible SSCs. First, the bulk Cu2O was thermally driven to migrate and diffuse within the tangent graphene oxide membranes (GOM) interface, drilling plenty of channels in the GOM. Then, the volatile and atomic Cu1Ox species would diffuse through the corroded channels. At last, the Cu1Ox species with strong causticity would corrode the C-N support by breaking the Cu-O bonds and releasing CO2. Hence, the atomic Cu species were eventually anchored in the C-N support by coordination with dangling N-rich defects, forming the Cu SSCs. The fabricated Cu SSCs exhibited an excellent performance in sterilizing bacteria. As our results displayed, Escherichia coli (E. coli.) was almost sterilized by Cu SSCs via activating persulfate. Compared to the traditional approaches employed by wastewater treatment plant, our Cu SSCs exhibit much better antibacterial effect, holding a great potential for practical bacterial disinfection.

Due to the large number of ionic liquids (ILs) and their potential environmental risk, assessing the toxicity of ILs by ecotoxicological experiment only is insufficient. Quantitative structure-activity relationship (QSAR) has been proven to be a quick and effective method to estimate the viscosity, melting points, and even toxicity of ILs. In this work, the LC50 values of 30 imidazolium-based ILs were determined with Caenorhabditis elegans as a model animal. Four suitable molecular descriptors were selected on the basis of genetic function approximation algorithm to construct a QSAR model with an R2 value of 0.938. The predicted lgLC50 in this work are in agreement with the experimental values, indicating that the model has good stability and predictive ability. Our study provides a valuable model to predict the potential toxicity of ILs with different sub-structures to the environment and human health.

Biosynthesis offers opportunities for cost-effective and sustainable production of semiconductor quantum dots (QDs), but is currently restricted by poor controllability on the synthesis process, resulting from limited knowledge on the assembly mechanisms and the lack of effective control strategies. In this work, we provide molecular-level insights into the formation mechanism of biogenic QDs (Bio-QDs) and its connection with the cellular substrate metabolism in Escherichia coli. Strengthening the substrate metabolism for producing more reducing power was found to stimulate the production of several reduced thiol-containing proteins (including glutaredoxin and thioredoxin) that play key roles in Bio-QDs assembly. This effectively diverted the transformation route of the selenium (Se) and cadmium (Cd) metabolic from Cd

Peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs) for wastewater treatment have recently attracted widespread interests. However, the degradation of organic pollutants via traditional radical-dominated pathway is severely limited by the side reactions between radicals and the co-existing inorganic anions, especially under high salinity conditions. Herein, an efficient Fe/O co-doped g-C3N4nanosheet catalyst was synthesized to dominantly activate PMS through a dual non-radical pathway with the singlet oxygen and high-valent iron-oxo species (Fe(V)=O). The rapid degradation of model pollutant bisphenol A (BPA) was achieved by dosing PMS (1 mM), catalyst (0.1 g/L) in a simulated high-salt wastewater (≥200 mM) of the developed Fe/O-doped g-C3N4+PMS system with a reaction rate constant of 1204-fold higher than that in g-C3N4+PMS system. The O and Fe co-dopants could reconfigurate the electronic structure of pristine g-C3N4 to produce more non-radical active species. The formed Fe(V)=O played a main role in the BPA degradation by promoting electron transfer from BPA molecule to the "metastable PMS/catalyst complex", which was verified by electrochemical tests and density functional theory calculations. The auxiliary transient productions of ·OH+SO4·- species were also favorable for the pollutant degradation. Excellent reusability in a wide pH range confirmed the practical application prospects of the Fe/O-doped g-C3N4+PMS system. The successive addition of PMS with a low dosage into the system rich in pollutants was confirmed to favor the PMS utilization. Our work unveils the potential applications of a non-radical dominated process for the decontamination of organic pollutants in saline water.

FeNi-based nanomaterials with bimetallic alloying effect deliver a great promise as an efficient electrocatalyst for oxygen evolution reaction (OER). However, the reconstruction to generate in-situ catalytically FeNi-based oxides or hydroxides during OER process and high electrical conductivity demand foster the great pursuit of the rational design of FeNi-based OER electrocatalyst a big challenge. Herein, we design and fabricate a nanostructured metallic FeNi2S4 as a highly efficient OER electrocatalyst. This catalyst exhibits an overpotential of (250 mV) and a Tafel slope (62 mV dec−1), that outperforms the benchmark of commercial RuO2. The experimental results demonstrate that the alloying effect and the superior electrical conductivity, endow it a great electrocatalytic performance. Such a nanostructured metallic OER electrocatalyst shows a great promise in water splitting.

Converting CO2 into valuable chemicals and fuels is one of the most practical routes for reducing CO2 emissions while fossil fuels continue to dominate the energy sector. Noble-metal-free NiFe bimetal nanoparticles have shown good catalytic activity in CO2 conversion. Herein we theoretically evaluated the catalytic performance and possible mechanisms of NiFe-based nanoclusters for hydrogenating CO2 to form formic acid and CO through bicarbonate by using a periodic and self-consistent density functional theory (DFT) simulation. The theoretical results illustrated that NiFe nanoclusters could have good catalytic activity and selectivity for HCO3− reduction to formic acid and the possible pathway is that HCO3− preferred to react with adsorbed H atoms of H2 on NiFe alloy nanoclusters through the carbon atom site. Moreover, the NiFe alloy nanoclusters with the Fe atom exposed on the surface of the Ni cluster showed better performance with a lower energy barrier compared to that with Fe doped in the corner of the Ni cluster. However, the generation of CO from HCO3− reduction was shown to be neither thermodynamically nor kinetically favorable on NiFe alloy nanoclusters. Additionally, the simulation results also suggested that it was thermodynamically unfavorable for further hydrogenated reduction of formic acid to formaldehyde on NiFe alloy nanoclusters themselves as well as supported on graphene. In summary, a molecular-level insight of CO2 reduction to valuable products on NiFe nanoclusters is offered in this study, which may provide some useful information for guiding the design of NiFe-based catalytic materials for efficient CO2 conversion to useful fuels.