Hydrogen peroxide (H
O
) is a powerful industrial oxidant and potential carbon-neutral liquid energy carrier. Sunlight-driven synthesis of H
O
from the most earth-abundant O
and seawater is highly ...desirable. However, the solar-to-chemical efficiency of H
O
synthesis in particulate photocatalysis systems is low. Here, we present a cooperative sunlight-driven photothermal-photocatalytic system based on cobalt single-atom supported on sulfur doped graphitic carbon nitride/reduced graphene oxide heterostructure (Co-CN@G) to boost H
O
photosynthesis from natural seawater. By virtue of the photothermal effect and synergy between Co single atoms and the heterostructure, Co-CN@G enables a solar-to-chemical efficiency of more than 0.7% under simulated sunlight irradiation. Theoretical calculations verify that the single atoms combined with heterostructure significantly promote the charge separation, facilitate O
absorption and reduce the energy barriers for O
reduction and water oxidation, eventually boosting H
O
photoproduction. The single-atom photothermal-photocatalytic materials may provide possibility of large-scale H
O
production from inexhaustible seawater in a sustainable way.
Selective uranium extraction from seawater is challenging because of ubiquitous marine biofouling and poor reusability of adsorbents. A reusable atomic-scale tungsten nanozyme integrating uranium ...capture capacity and intrinsic haloperoxidase-like activity is constructed, resulting in strong antibiofouling ability and superb reusability for uranium extraction after consecutive multiple regeneration cycles in bio-aggressive seawater.
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•Atomically dispersed tungsten is anchored in metal organic frameworks (W-UiO).•The presence of atomic-scale tungsten endows W-UiO with haloperoxidase-mimicking activity.•W-UiO nanozyme exerts strong antibacterial activity and inhibition effect against marine microbial colonization.•Such nanozyme exhibits excellent reusability for uranium extraction from seawater.
Uranium is the essential element for nuclear power industry. Selective uranium extraction from seawater is very attractive, but challenging because ubiquitous marine biofouling seriously impairs the uranium extraction capacity and reusability of absorbents in bio-aggressive seawater. Herein, we construct a reusable nanozyme for uranium recovery from seawater based on atomically dispersed tungsten anchored on metal organic frameworks (W-UiO). We illustrate that W-UiO nanozyme mimics naturally occurring vanadium haloperoxidase that catalytically converting halides to biocidal hypobromous acid, inducing strong antibiofouling activity against marine microbial colonization. As demonstrated, W-UiO nanozyme shows superb reusability in raw seawater simultaneously, preserving a 78.0% of its initial uranium capture capacity (6.8 times higher than its pristine counterpart) after five consecutive adsorption-desorption cycles. This study is anticipated to spur rationally realizing robust absorbents by mimicking the natural enzymes for practical application in uranium recovery from seawater.
Sunlight‐driven photoreduction of the environmentally mobile uranyl (VI) to less soluble tetravalent uranium is of considerable value to environmental sustainability, yet the pursuit for ...high‐performance semiconductors is plagued by the current disadvantages of inferior charge separation/migration. This study reports that a nickel single atom isolated on a sulfur‐functionalized graphitic carbon nitride/reduced graphene oxide 2D heterostructure enables exceptional uranyl photoreduction. Under only 11 min of visible light irradiation, the single atom anchored semiconductor yields a high removal rate of 99.8% and a record‐high extraction capacity of 4144 mg g−1 in uranyl‐containing wastewater and seawater. Theoretical calculations confirm that the remarkable uranyl photoreduction originates from the synergetic effect of Ni single atoms and intimate heterojunction establishment that can not only promote the separation/migration of photoexcited carriers, but also greatly reduce the energy barrier of uranyl reduction. This study showcases the exciting potential of single atom semiconductors for efficient uranyl removal from uranium‐contaminated aqueous environments.
Photoreduction of environmentally mobile uranyl (VI) from uranium‐contaminated aqueous environments to less soluble U (IV) solid is of considerable value to environmental sustainability. A single‐site nickel mediated heterostructure in which nickel single atoms are isolated on sulfur‐functionalized graphitic carbon nitride/reduced graphene oxide is created to enable efficient uranyl photoreduction, yielding a record‐fast removal rate in uranium‐contaminated aqueous environments.
Biofouling is a common and expensive problem in medical, food, and maritime industries. Artificial nanozymes as functional mimics of haloperoxidases that boost the formation of cytotoxic hypohalous ...acids from halides and H2O2 are showing increasing potential as a novel class of ecofriendly antibiofouling materials to combat biofilm formation. A photothermal nanozyme (Mo SA‐N/C) with Mo single atoms as active sites that exhibits haloperoxidase‐mimicking capacity is herein developed. Density functional theory calculations indicate that hydroxyl radical from H2O2 dissociation is the key intermediate for hypobromous acid formation. Upon photoirradiation, Mo SA‐N/C generates heat and accelerates the reaction kinetics substantially. Finally, it is demonstrated that Mo SA‐N/C exerts superior broad‐spectrum antibacterial activity and can be applied as an effective coating additive for inhibiting biofouling in real marine conditions. Taken together, this study opens an avenue for developing biocompatible and photo‐response artificial enzymes for our fight against marine biofouling.
Utilizing solar‐driven thermal effect to amplify the reaction kinetics is of great significance in biomimetic chemistry. A single‐site molybdenum photothermal nanozyme is constructed to mimic naturally occurring haloperoxidase. Upon λ > 420 nm photoirradiation, the thermal effect accelerates the generation of biocidal hypohalous acid, enabling superior broad‐spectrum antibacterial activity and significant antibiofouling ability in bio‐aggressive seawater.
Nature has evolved diverse strategies to battle surface biofouling colonization and thus provides us novel insights into designing and developing advanced nontoxic antibiofouling materials and ...technologies. Mimicking the defense mechanisms of natural haloperoxidases in marine algae in response to biofilm colonization, here we show that the less active MoS2 shows efficient haloperoxidase-mimicking activity through judicious transition metal engineering. Cobalt-doped MoS2 (Co–MoS2) displays an excellent haloperoxidase-mimicking performance in catalyzing the Br– oxidation into germicidal HOBr, roughly 2 and 23 times higher than the nickel-doped MoS2 and pristine MoS2, respectively. Accordingly, Co–MoS2 shows an outstanding antimicrobial effect against drug-resistant bacteria and antibiofouling performance in real field tests in marine environments. The realization of robust haloperoxidase-mimicking activity of MoS2 via metal engineering may open a new avenue to design highly active transition metal dichalcogenides for antibacterial and antibiofouling applications.
Coupling the photoproduction of solar fuel and value‐added chemicals is highly attractive, as it maximizes the utilization of incident sunlight and the economic value of photocatalytic reactions. ...Constructing intimate semiconductor heterojunction for these reactions is highly desirable due to accelerated charge separation at the interfacial contact, but is challenged by material synthesis. Here, an active heterostructure bearing intimate interface, consisting of discrete Co9S8 nanoparticles anchored on cobalt doped ZnIn2S4 using a facile in situ one‐step strategy, can drive photocatalytic co‐production of H2O2 and benzaldehyde from a two‐phase water/benzyl alcohol system with spatial product separation is reported. The heterostructure yields a high production amount of 49.5 and 55.8 mmol L−1 for H2O2 and benzaldehyde under visible‐light soaking, respectively. The synchronous elemental Co doping and intimate heterostructure establishment substantially improve the overall reaction kinetics. Mechanism studies reveal that H2O2 generated in the aqueous phase undergoes photodecomposition forming hydroxyl radical, which is subsequently transferred into the organic phase to oxidize benzyl alcohol into benzaldehyde. This study offers fertile guidelines for creating integrated semiconductors and broadens the avenue toward the coupled production of solar fuels and industrially important chemicals.
The generation of undesired biofouling in medical and engineering applications results in a reduction in function and durability. Copying functionalities of natural enzymes to combat biofouling by ...artificial nanomaterials is highly attractive but still challenged by the inferior catalytic activity and specificity principally because of low densities of active sites. Here, an innovate strategy is demonstrated to stabilize high‐density ultrasmall ceria clusters on zirconia for biofouling prevention. Benefiting from the unique structure, CeO2@ZrO2 nanozyme can significantly enhance the haloperoxidase‐mimicking activity in catalyzing the oxidation of bromide with H2O2 into biocidal hypobromous acid as a result of abundant defects and surface strong acidity sites, inducing impressive antibacterial and antibiofouling capacity compared with that of pristine CeO2. This work is expected to open a new avenue for the rational design of cluster catalysts for various targeting catalytic applications.
Downsizing metal oxides to the sub‐nano scale is of significance for maximizing active component utilization and realizing superb catalytic performance. A nanozyme with high‐density ultrasmall ceria clusters (≈0.8 nm) stabilized on zirconia substrates is constructed, achieving significantly enhanced haloperoxidase‐mimicking activity and impressive antibiofouling ability in bioaggressive seawater.
Coupling the photoproduction of solar fuel and value-added chemicals is highly attractive, as it maximizes the utilization of incident sunlight and the economic value of photocatalytic reactions. ...Constructing intimate semiconductor heterojunction for these reactions is highly desirable due to accelerated charge separation at the interfacial contact, but is challenged by material synthesis. Here, an active heterostructure bearing intimate interface, consisting of discrete Co
S
nanoparticles anchored on cobalt doped ZnIn
S
using a facile in situ one-step strategy, can drive photocatalytic co-production of H
O
and benzaldehyde from a two-phase water/benzyl alcohol system with spatial product separation is reported. The heterostructure yields a high production amount of 49.5 and 55.8 mmol L
for H
O
and benzaldehyde under visible-light soaking, respectively. The synchronous elemental Co doping and intimate heterostructure establishment substantially improve the overall reaction kinetics. Mechanism studies reveal that H
O
generated in the aqueous phase undergoes photodecomposition forming hydroxyl radical, which is subsequently transferred into the organic phase to oxidize benzyl alcohol into benzaldehyde. This study offers fertile guidelines for creating integrated semiconductors and broadens the avenue toward the coupled production of solar fuels and industrially important chemicals.
Artificial nanozymes exerting enzyme functionality are recognized as promising alternatives of natural enzymes in biomimetic chemistry. Natural haloperoxidases that utilize hydrogen peroxide (H2O2) ...to catalytically convert halide into strong biocidal hypohalous acid hold great promise for thwarting biofouling, while their practical application remains highly questionable as instability of natural enzymes and inadequate H2O2. Herein a semiconducting nanozyme consisting of chromium single atoms coordinated on carbon nitride (Cr‐SA‐CN) that performs bifunctional roles of nonsacrificial H2O2 photosynthesis and haloperoxidase‐mimicking activity for antibiofouling is constructed. Such nanozyme is capable of generating H2O2 from water and O2 upon visible‐light illumination, and then sustainably self‐supplying H2O2 for haloperoxidase‐mimicking reaction in a sequential manner. This dual‐activity Cr‐SA‐CN overcomes H2O2 dilemma and yields hypobromous acid continuously, inducing remarkable bactericidal capability. When used as an eco‐friendly coating additive, it is successfully demonstrated that Cr‐SA‐CN enables an inert surface against marine biofouling. Thereby, this study not only illustrates an attractive strategy for antibiofouling but also opens an avenue to construct valuable nanoplatform with multifunctionality for future applications.
A system, namely chromium single atoms coordinated on carbon nitride, is designed. Chromium incorporation endows the system with coupled bifunctions of hydrogen peroxide photosynthesis and haloperoxidase‐mimicking activity, enabling remarkable bactericidal capability and impressive antibiofouling performance. This multifunctional biomimetic design surmounts the natural haloperoxidases, paving a way for constructing advanced nanomaterials for a variety of antibiofilm processes.
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