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1.
J Am Chem Soc ; 2020 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-32530616

RESUMO

Photocatalytic nitrogen fixation represents a green alternative to the conventional Haber-Bosch process in the conversion of nitrogen to ammonia. In this study, a series of Bi5O7Br nanostructures were synthesized via a facile, low-temperature thermal treatment procedure, and their photocatalytic activity toward nitrogen fixation was evaluated and compared. Spectroscopic measurements showed that the tubular Bi5O7Br sample prepared at 40 °C (Bi5O7Br-40) exhibited the highest electron-transfer rate among the series, producing a large number of O2.- radicals and oxygen vacancies under visible-light photoirradiation and reaching a rate of photocatalytic nitrogen fixation of 12.72 mM·g-1·h-1 after 30 min of photoirradiation. The reaction dynamics was also monitored by in situ infrared measurements with a synchrotron radiation light source, where the transient difference between signals in the dark and under photoirradiation was analyzed and the reaction pathway of nitrogen fixation was identified. This was further supported by results from density functional theory calculations. The reaction energy of nitrogen fixation was quantitatively estimated and compared by building oxygen-enriched and anoxic models, where the change in the oxygen vacancy concentration was found to play a critical role in determining the nitrogen fixation performance. Results from this study suggest that Bi5O7Br with rich oxygen vacancies can be used as a high-performance photocatalyst for nitrogen fixation.

2.
J Am Chem Soc ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32130002

RESUMO

Harvesting solar energy for catalytic conversion of CO2 into valuable chemical fuels/feedstocks is an attractive yet challenging strategy to realize a sustainable carbon-cycle utilization. Homogeneous catalysts typically exhibit higher activity and selectivity as compared with heterogeneous counterparts, benefiting from their atomically dispersed catalytic sites and versatile coordination structures. However, it is still a "black box" how the coordination and electronic structures of catalysts dynamically evolve during the reaction, forming the bottleneck for understanding their reaction pathways. Herein, we demonstrate to track the mechanistic pathway of photocatalytic CO2 reduction using a terpyridine nickel(II) complex as a catalyst model. Integrated with a typical homogeneous photosensitizer, the catalytic system offers a high selectivity of 99% for CO2-to-CO conversion with turnover number and turnover frequency as high as 2.36 × 107 and 385.6 s-1, respectively. We employ operando and time-resolved X-ray absorption spectroscopy, in combination with other in situ spectroscopic techniques and theoretical computations, to track the intermediate species of Ni catalyst in the photocatalytic CO2 reduction reaction for the first time. Taken together with the charge dynamics resolved by optical transient absorption spectroscopy, the investigation elucidates the full mechanistic reaction pathway including some key factors that have been often overlooked. This work opens the "black box" for CO2 reduction in the system of homogeneous catalysts and provides key information for developing efficient catalysts toward artificial photosynthesis.

3.
Chem Rev ; 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32186373

RESUMO

Single-atom photocatalysts have shown their compelling potential and arguably become the most active research direction in photocatalysis due to their fascinating strengths in enhancing light-harvesting, charge transfer dynamics, and surface reactions of a photocatalytic system. While numerous comprehensions about the single-atom photocatalysts have recently been amassed, advanced characterization techniques and vital theoretical studies are strengthening our understanding on these fascinating materials, allowing us to forecast their working mechanisms and applications in photocatalysis. In this review, we begin by describing the general background and definition of the single-atom photocatalysts. A brief discussion of the metal-support interactions on the single-atom photocatalysts is then provided. Thereafter, the current available characterization techniques for single-atom photocatalysts are summarized. After having some fundamental understanding on the single-atom photocatalysts, their advantages and applications in photocatalysis are discussed. Finally, we end this review with a look into the remaining challenges and future perspectives of single-atom photocatalysts. We anticipate that this review will provide some inspiration for the future discovery of the single-atom photocatalysts, manifestly stimulating the development in this emerging research area.

4.
Nanoscale ; 12(4): 2507-2514, 2020 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-31930257

RESUMO

Harvesting solar energy to convert carbon dioxide (CO2) into fossil fuels shows great promise to solve the current global problems of energy crisis and climate change. To achieve this goal, it is desirable to develop efficient catalysts with visible light response to cater for the solar spectrum. CdTe QDs are ideal candidates for absorbing visible light, but it is difficult to directly perform CO2 reduction due to the lack of effective catalytic sites. Herein, we report a strategy for the activation of mercaptopropionic acid (MPA)-capped CdTe QDs for visible-light-driven CO2 reduction, in which iron ions (Fe2+) are immobilized onto CdTe QDs using l-cysteine as a bridging ligand (CdTe-b-Fe). This ligand bridging strategy can immobilize Fe2+ ions on the surface of CdTe QDs as catalytic sites, and these catalytic sites can be conveniently adjusted by directly adding different types or numbers of metal ions. In addition to effectively immobilizing catalytic sites, the bridging ligands can also provide a pathway for electron transport between CdTe QDs and the catalytic sites. The CdTe-b-Fe QD system based on the ligand bridging strategy exhibits excellent catalytic properties: the yield of CH4/CO (two products together) is 126 µmol g-1 h-1, and the selectivity for carbon-based products approaches 98%. This work presents a facile strategy for immobilizing catalytic sites on QDs and provides a platform for designing efficient visible-light driven catalysts for CO2 reduction.

5.
Artigo em Inglês | MEDLINE | ID: mdl-31922641

RESUMO

Single-atom catalysts are promising platforms for heterogeneous catalysis, especially for clean energy conversion, storage, and utilization. Although great efforts have been made to examine the bonding and oxidation state of single-atom catalysts before and/or after catalytic reactions, when information about dynamic evolution is not sufficient, the underlying mechanisms are often overlooked. Herein, we report the direct observation of the charge transfer and bond evolution of a single-atom Pt/C3 N4 catalyst in photocatalytic water splitting by synchronous illumination X-ray photoelectron spectroscopy. Specifically, under light excitation, we observed Pt-N bond cleavage to form a Pt0 species and the corresponding C=N bond reconstruction; these features could not be detected on the metallic platinum-decorated C3 N4 catalyst. As expected, H2 production activity (14.7 mmol h-1 g-1 ) was enhanced significantly with the single-atom Pt/C3 N4 catalyst as compared to metallic Pt-C3 N4 (0.74 mmol h-1 g-1 ).

6.
Chem Sci ; 10(31): 7310-7326, 2019 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-31768231

RESUMO

Heterogeneous thermocatalytic and electrocatalytic conversion of CO x including CO and CO2 to value-added products, which can be performed through three promising approaches - syngas conversion, CO2 hydrogenation and CO2 electroreduction, are highly important to achieving a carbon-neutral cycle associated with the continuing consumption of fossil fuels. Toward the formation of value-added C2+ products, precise regulation of C-C coupling requires rational design of catalysts in all the three approaches, which usually share similar fundamentals from the viewpoint of surface science. In this article, we outline the recent advances in catalyst design for controlling C-C coupling in syngas conversion, CO2 hydrogenation and CO2 electroreduction from the viewpoint of surface science. Specifically, the fundamental insights are provided for each conversion approach, which makes a connection between thermocatalysis and electrocatalysis in terms of catalytic site design. Finally, the challenges and opportunities are discussed in the hope of inspiring new ideas to achieve more efficient C-C coupling in thermocatalytic and electrocatalytic CO x conversion.

7.
Nat Commun ; 10(1): 2840, 2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31253761

RESUMO

The design of efficient and stable photocatalysts for robust CO2 reduction without sacrifice reagent or extra photosensitizer is still challenging. Herein, a single-atom catalyst of isolated single atom cobalt incorporated into Bi3O4Br atomic layers is successfully prepared. The cobalt single atoms in the Bi3O4Br favors the charge transition, carrier separation, CO2 adsorption and activation. It can lower the CO2 activation energy barrier through stabilizing the COOH* intermediates and tune the rate-limiting step from the formation of adsorbed intermediate COOH* to be CO* desorption. Taking advantage of cobalt single atoms and two-dimensional ultrathin Bi3O4Br atomic layers, the optimized catalyst can perform light-driven CO2 reduction with a selective CO formation rate of 107.1 µmol g-1 h-1, roughly 4 and 32 times higher than that of atomic layer Bi3O4Br and bulk Bi3O4Br, respectively.

8.
Nanoscale ; 11(23): 11064-11070, 2019 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-31166355

RESUMO

Photocatalytic conversion of CO2 into carbonaceous chemical fuels and building blocks is an intriguing strategy for solving fossil energy crisis and reducing CO2 emission. Recently, development of atomically dispersed catalytic sites for photocatalytic CO2 reduction has sparked tremendous interest as their coordinatively unsaturated states, tunable electronic structures and well-defined active sites provide versatile knobs for tuning CO2 conversion. While this Minireview mainly highlights recent key developments in this important research field and elucidates the common fundamentals behind various materials systems, it also provides insights into the future development and emphasizes opportunities and challenges.

9.
Magn Reson Imaging ; 61: 137-142, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31129280

RESUMO

PURPOSE: Only a few studies have investigated the brain morphology abnormalities in structural MRI in patients with drug-naïve idiopathic generalized epilepsy (IGE) and mainly focused on brain volume changes. In the present study, we aimed to investigate the changes in three morphologic measurement differences including cortical thickness, cortical volume, and surface area using FreeSurfer in a pediatric cohort of recent-onset, drug-naïve IGE. METHODS: Forty-five recent-onset, drug-naïve patients diagnosed with IGE and 32 demographically matched healthy controls were recruited. All participants underwent structural MRI scans with a 3.0 T MR system. FreeSurfer, an automated cortical surface reconstruction toolbox, was applied to compare the cortical morphology between patients and controls. The brain regions with significant group differences after multiple comparison correction were extracted in common space for each patient, and then correlated with their clinical characteristics (including onset age, duration of epilepsy, and mini-mental state examination (MMSE)) using partial correlation analysis with age, sex and intracranial volume as covariates. RESULTS: Compared with controls, IGE patients showed decreased cortical thickness in the left rostral middle frontal gyrus, decreased cortical volume in the right cuneus and left superior frontal gyrus that extended to the precentral gyrus, and decreased surface area in the right cuneus and right inferior parietal gyrus. None of these regions showed significant relationships with clinical measurements in the patient group. CONCLUSION: Our findings suggest that cortical thickness, cortical volume, and surface area changes occurred in the early stage of IGE. These findings provide structural neuroimaging evidence underlying the pathology of IGE.


Assuntos
Mapeamento Encefálico , Epilepsia Generalizada/diagnóstico por imagem , Lobo Frontal/diagnóstico por imagem , Imagem por Ressonância Magnética , Córtex Pré-Frontal/diagnóstico por imagem , Adolescente , Adulto , Estudos de Casos e Controles , Criança , Pré-Escolar , Epilepsia/diagnóstico por imagem , Feminino , Lobo Frontal/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Reconhecimento Automatizado de Padrão , Córtex Pré-Frontal/patologia , Reprodutibilidade dos Testes
10.
J Am Chem Soc ; 141(19): 7807-7814, 2019 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-31038309

RESUMO

Nitrogen fixation in a simulated natural environment (i.e., near ambient pressure, room temperature, pure water, and incident light) would provide a desirable approach to future nitrogen conversion. As the N≡N triple bond has a thermodynamically high cleavage energy, nitrogen reduction under such mild conditions typically undergoes associative alternating or distal pathways rather than following a dissociative mechanism. Here, we report that surface plasmon can supply sufficient energy to activate N2 through a dissociative mechanism in the presence of water and incident light, as evidenced by in situ synchrotron radiation-based infrared spectroscopy and near ambient pressure X-ray photoelectron spectroscopy. Theoretical simulation indicates that the electric field enhanced by surface plasmon, together with plasmonic hot electrons and interfacial hybridization, may play a critical role in N≡N dissociation. Specifically, AuRu core-antenna nanostructures with broadened light adsorption cross section and active sites achieve an ammonia production rate of 101.4 µmol g-1 h-1 without any sacrificial agent at room temperature and 2 atm pressure. This work highlights the significance of surface plasmon to activation of inert molecules, serving as a promising platform for developing novel catalytic systems.

11.
J Am Chem Soc ; 140(48): 16514-16520, 2018 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-30407807

RESUMO

Development of visible-light photocatalytic materials is an ultimate goal for solar-driven CO2 conversion. Au nanoclusters (NCs) may potentially serve as components for harvesting visible light but can hardly perform solar-driven CO2 reduction due to the lack of catalytic sites. Herein, we report an effective strategy for turning Au nanoclusters catalytically active for visible-light CO2 reduction, in which metal cations (Fe2+, Co2+, Ni2+, and Cu2+) are grafted to the Au NCs using l-cysteine as a bridging ligand. The metal-S bonding bridge facilitates the electron transfer from Au NCs to metal cations so that the grafted metal cations can receive photoinduced electrons and work as catalytic sites for CO2 reduction. The varied d-band centers and binding energies with CO2 for different metal cations allow tuning electron transfer efficiency and CO2 activation energy. Furthermore, the photostability of Au NCs-based catalyst can be significantly enhanced through the encapsulation with metal-organic frameworks. This work opens a new door for the photocatalyst design based on metal clusters and sheds light on the surface engineering of metal clusters toward specific applications.

12.
Angew Chem Int Ed Engl ; 57(45): 14847-14851, 2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30178910

RESUMO

Solar-driven reduction of CO2 , which converts inexhaustible solar energy into value-added fuels, has been recognized as a promising sustainable energy conversion technology. However, the overall conversion efficiency is significantly limited by the inefficient charge separation and sluggish interfacial reaction dynamics, which resulted from a lack of sufficient active sites. Herein, Bi12 O17 Cl2 superfine nanotubes with a bilayer thickness of the tube wall are designed to achieve structural distortion for the creation of surface oxygen defects, thus accelerating the carrier migration and facilitating CO2 activation. Without cocatalyst and sacrificing reagent, Bi12 O17 Cl2 nanotubes deliver high selectivity CO evolution rate of 48.6 µmol g-1 h-1 in water (16.8 times than of bulk Bi12 O17 Cl2 ), while maintaining stability even after 12 h of testing. This paves the way to design efficient photocatalysts with collaborative optimizing charge separation and CO2 activation towards CO2 photoreduction.

13.
J Genet ; 97(4): 1007-1011, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30262714

RESUMO

Congenital anophthalmia is a rare eye anomaly which lacks a recognizable eye in the orbit. It can be isolated (nonsyndromic) or be observed as a sign of other diseases (syndromic). A Chinese infant was born with bilateral anophthalmia and palpebral fissure closures. Ocular and systemic examinations were performed, and genomic DNA was prepared from peripheral leukocytes. The coding exons and the adjacent intrinsic sequence of SOX2 were analysed by Sanger sequencing. A c.70_89del (p. Asn24ArgfsX65; rs398123693) mutation in SOX2 was identified in the Chinese infant with bilateral clinical anophthalmia and sensorineural hearing loss. Thismutation was not detected in the unaffected parents and 150 unaffected control individuals.Mutation in SOX2 is associated with bilateral clinical anophthalmia and probablywith other anomalies in the Chinese infant. Until nowhearing loss has not been reported in individuals with SOX2 mutation. The results remind us that clinical anophthalmia may be accompanied by sensorineural hearing loss and may be associated with SOX2 mutation, and it will contribute to improving diagnosis and patient care. Given that children with anophthalmia already have reduced sight, it seems worthwhile to make a point of careful vigilance on hearing for all such patients.


Assuntos
Anoftalmia/genética , Perda Auditiva Neurossensorial/genética , Fatores de Transcrição SOXB1/genética , Anoftalmia/fisiopatologia , Predisposição Genética para Doença , Perda Auditiva Neurossensorial/fisiopatologia , Humanos , Lactente , Deleção de Sequência
14.
Chemistry ; 24(69): 18398-18402, 2018 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-30102805

RESUMO

Metal-containing nanocrystals with well-designed surface structures represent a class of model systems for revealing the fundamental physical and chemical processes involved in heterogeneous catalysis. Herein it is shown how surface modification can be utilized as an efficient strategy for controlling the surface electronic state of catalysts and, thus, for tuning their catalytic activity. As model catalysts, the Pd-tetrahedron-TiO2 nanostructures, modified on the surface with different foreign atoms, showed a varied activity in the catalytic decomposition of formic acid towards H2 production. The catalytic activity increases with a reduction in the work function of modified atoms; this reduction can be well explained by a surface polarization mechanism. In this hybrid system, the difference in the work functions of Pd and modified atoms results in surface polarization on the Pd surface and, thus, in the tuning of its charge state. Together with the Schottky junction between TiO2 and metals, the tuned charge state enables the promotion of catalytic efficiency in the catalytic decomposition of formic acid to H2 and CO2 .

15.
Hum Pathol ; 79: 93-101, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29792893

RESUMO

Fusobacterium nucleatum in the tumor microenvironment plays an important role in the development of colorectal cancer. The underlying mechanism of action, however, remains to be elucidated. We evaluated the relation of F nucleatum amount to thymocyte selection-associated high-mobility group box (TOX) protein expression and CD4+ T-cell density in 138 human colorectal tissues. TOX expression and CD4+ T-cell density in Fnucleatum-negative tissues were significantly higher compared to those in Fnucleatum-positive tissues (P < .001 and P = .002, respectively). We found a negative correlation between F nucleatum abundance and TOX expression (P < .001) and CD4+ T-cell density (P < .001). TOX expression in normal mucosa, hyperplastic polyps, and adenomas was significantly higher than in sessile serrated adenomas and different stages of carcinomas (P < .05). Moreover, CD4+ T-cell density in high-TOX expression tissues was significantly higher than in low-TOX expression tissues (P = .003). A positive correlation was found between TOX expression and CD4+ T-cell density in colorectal tissues (Spearman correlation coefficient: 0.362, 95% confidence interval: 0.051-0.641, P = .022). Our findings suggest that F nucleatum may suppress antitumor immune responses by decreasing CD4+ T-cell density and TOX expression in the progression of colorectal cancer.


Assuntos
Biomarcadores Tumorais/análise , Linfócitos T CD4-Positivos/imunologia , Neoplasias Colorretais/química , Infecções por Fusobacterium/microbiologia , Fusobacterium nucleatum/isolamento & purificação , Proteínas de Grupo de Alta Mobilidade/análise , Linfócitos do Interstício Tumoral/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Linfócitos T CD4-Positivos/microbiologia , Neoplasias Colorretais/imunologia , Neoplasias Colorretais/microbiologia , Neoplasias Colorretais/patologia , Feminino , Infecções por Fusobacterium/imunologia , Fusobacterium nucleatum/genética , Fusobacterium nucleatum/imunologia , Interações Hospedeiro-Patógeno , Humanos , Linfócitos do Interstício Tumoral/microbiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Evasão Tumoral , Microambiente Tumoral
16.
Small ; 14(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29149529

RESUMO

The electrocatalytic oxygen evolution reaction (OER) is a highly important reaction that requires a relatively high overpotential and determines the rate of water splitting-a process for producing hydrogen. The overall OER performance is often largely limited by uncontrollable interface when active catalysts are loaded on conductive supports, for which polymer binders are widely used, but inevitably block species transportation channels. Here, a scalable fabrication approach to freestanding graphitized carbon nanofiber networks is reported, which provides abundant sites for in situ growing Fe/Ni catalysts with the improved interface. The fabricated hybrid membrane exhibits high activity and durability toward OER, with an overpotential of 280 mV at a geometrical current density of 10 mA cm-2 and a Tafel slope of 30 mV dec-1 in alkaline medium. As implemented as a freestanding electrode, the 3D hybrid structure achieves further enhanced OER performance with an overpotential down to 215 mV at 10 mA cm-2 . This work provides fresh insights into rationally fabricating OER electrocatalysts from the angle of electrode design.

17.
Small ; 13(31)2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28640522

RESUMO

Adsorption and activation of molecules on a surface holds the key to heterogeneous catalysis toward aerobic oxidative reactions. To achieve high catalytic activities, a catalyst surface should be rationally tailored to interact with both organic substrates and oxygen molecules. Here, a facile bottom-up approach to defective tungsten oxide hydrate (WO3 ·H2 O) nanosheets that contain both surface defects and lattice water is reported. The defective WO3 ·H2 O nanosheets exhibit excellent catalytic activity for aerobic coupling of amines to imines. The investigation indicates that the oxygen vacancies derived from surface defects supply coordinatively unsaturated sites to adsorb and activate oxygen molecules, producing superoxide radicals. More importantly, the Brønsted acid sites from lattice water can contribute to enhancing the adsorption and activation of alkaline amine molecules. The synergistic effect of oxygen vacancies and Brønsted acid sites eventually boosts the catalytic activity, which achieves a kinetic rate constant of 0.455 h-1 and a turnover frequency of 0.85 h-1 at 2 h, with the activation energy reduced to ≈35 kJ mol-1 . This work provides a different angle for metal oxide catalyst design by maneuvering subtle structural features, and highlights the importance of synergistic effects to heterogeneous catalysts.

18.
Small ; 13(23)2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28452397

RESUMO

Low power consumption and minimal potential hazards are ultimate goals for the modern development of chemical manufacturing; however, it often reduces the selectivity of chemical reactions by implementing a new reaction system. A nanocatalyst design is reported for achieving efficient and selective alkyne semihydrogenation through the photocatalytic hydrogen transfer from water, which avoids the use of a heat source and explosive H2 . The PdPt catalytic sites that are implemented on the TiO2 photocatalyst hold the key to achieving both high activity and selectivity. As compared with pure Pd or Pt, the alloy cocatalysts can better harness H diffusion/desorption for selective semihydrogenation as well as suppress competitive H2 evolution. This work opens up new possibilities for green and selective alkyne semihydrogenation and highlights the importance of lattice engineering to catalytic selectivity.

19.
J Am Chem Soc ; 139(12): 4486-4492, 2017 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-28276680

RESUMO

Photocatalytic conversion of CO2 to CH4, a carbon-neutral fuel, represents an appealing approach to remedy the current energy and environmental crisis; however, it suffers from the large production of CO and H2 by side reactions. The design of catalytic sites for CO2 adsorption and activation holds the key to address this grand challenge. In this Article, we develop highly selective sites for photocatalytic conversion of CO2 to CH4 by isolating Cu atoms in Pd lattice. According to our synchrotron-radiation characterizations and theoretical simulations, the isolation of Cu atoms in Pd lattice can play dual roles in the enhancement of CO2-to-CH4 conversion: (1) providing the paired Cu-Pd sites for the enhanced CO2 adsorption and the suppressed H2 evolution; and (2) elevating the d-band center of Cu sites for the improved CO2 activation. As a result, the Pd7Cu1-TiO2 photocatalyst achieves the high selectivity of 96% for CH4 production with a rate of 19.6 µmol gcat-1 h-1. This work provides fresh insights into the catalytic site design for selective photocatalytic CO2 conversion, and highlights the importance of catalyst lattice engineering at atomic precision to catalytic performance.

20.
Angew Chem Int Ed Engl ; 56(15): 4206-4210, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28296159

RESUMO

Z-scheme water splitting is a promising approach based on high-performance photocatalysis by harvesting broadband solar energy. Its efficiency depends on the well-defined interfaces between two semiconductors for the charge kinetics and their exposed surfaces for chemical reactions. Herein, we report a facile cation-exchange approach to obtain compounds with both properties without the need for noble metals by forming Janus-like structures consisting of γ-MnS and Cu7 S4 with high-quality interfaces. The Janus-like γ-MnS/Cu7 S4 structures displayed dramatically enhanced photocatalytic hydrogen production rates of up to 718 µmol g-1 h-1 under full-spectrum irradiation. Upon further integration with an MnOx oxygen-evolution cocatalyst, overall water splitting was accomplished with the Janus structures. This work provides insight into the surface and interface design of hybrid photocatalysts, and offers a noble-metal-free approach to broadband photocatalytic hydrogen production.

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