Multifunctional Interface Layer Constructed by Trace Zwitterions for Highly Reversible Zinc Anodes.

The inhomogeneous plating/stripping of Zn anode, attributed to dendrite growth and parasitic reactions at the electrode/electrolyte interface, severely restricts its cycling life-span. Here, trace zwitterions (trifluoroacetate pyridine, TFAPD) are introduced into the aqueous electrolyte to construct a multifunctional interface that enhances the reversibility of Zn anode. The TFA- anions with strong specific adsorption adhere onto the Zn surface to reconstruct the inner Helmholtz plane (IHP), preventing the hydrogen evolution and corrosion side reactions caused by free H2O. The Py+ cations accumulate on the outer Helmholtz plane (OHP) of Zn anode with the force of electric field during Zn2+ plating, forming a shielding layer to uniformize the deposition of Zn2+. Besides, the adsorbed TFA- and Py+ promote the desolvation process of Zn2+ resulting in fast reaction kinetics. Thus, the Zn||Zn cells present an outstanding cycling performance of more than 10000 hours. And even at 85 % utilization rate of Zn, it can stably cycle for over 200 hours at 10 mA cm-2 and 10 mAh cm-2. The Zn||I2 full cell exhibits a capacity retention of over 95 % even after 30000 cycles. Remarkably, the Zn||I2 pouch cells (95 mAh) deliver a high-capacity retention of 99 % after 750 cycles.

Botulinum toxin type A-targeted SPP1 contributes to neuropathic pain by the activation of microglia pyroptosis.

BACKGROUND: Neuropathic pain (NP) is the primary symptom of various neurological conditions. Patients with NP often experience mood disorders, particularly depression and anxiety, that can severely affect their normal lives. Microglial cells are associated with NP. Excessive inflammatory responses, especially the secretion of large amounts of pro-inflammatory cytokines, ultimately lead to neuroinflammation. Microglial pyroptosis is a newly discovered form of inflammatory cell death associated with immune responses and inflammation-related diseases of the central nervous system. AIM: To investigate the effects of botulinum toxin type A (BTX-A) on microglial pyroptosis in terms of NP and associated mechanisms. METHODS: Two models, an in vitro lipopolysaccharide (LPS)-stimulated microglial cell model and a selective nerve injury model using BTX-A and SPP1 knockdown treatments, were used. Key proteins in the pyroptosis signaling pathway, NLRP3-GSDMD, were assessed using western blotting, real-time quantitative polymerase chain reaction, and immunofluorescence. Inflammatory factors [interleukin (IL)-6, IL-1ß, and tumor necrosis factor (TNF)-α] were assessed using enzyme-linked immunosorbent assay. We also evaluated microglial cell proliferation and apoptosis. Furthermore, we measured pain sensation by assessing the delayed hind paw withdrawal latency using thermal stimulation. RESULTS: The expression levels of ACS and GSDMD-N and the mRNA expression of TNF-α, IL-6, and IL-1ß were enhanced in LPS-treated microglia. Furthermore, SPP1 expression was also induced in LPS-treated microglia. Notably, BTX-A inhibited SPP1 mRNA and protein expression in the LPS-treated microglia. Additionally, depletion of SPP1 or BTX-A inhibited cell viability and induced apoptosis in LPS-treated microglia, whereas co-treatment with BTX-A enhanced the effect of SPP1 short hairpin (sh)RNA in LPS-treated microglia. Finally, SPP1 depletion or BTX-A treatment reduced the levels of GSDMD-N, NLPRP3, and ASC and suppressed the production of inflammatory factors. CONCLUSION: Notably, BTX-A therapy and SPP1 shRNA enhance microglial proliferation and apoptosis and inhibit microglial death. It improves pain perception and inhibits microglial activation in rats with selective nerve pain.

Cr doping and heterostructure-accelerated NiFe LDH reaction kinetics assist the MoS2 oxygen evolution reaction.

Although molybdenum disulfide (MoS2) has garnered significant interest as a potential catalyst for the oxygen evolution reaction (OER), its poor intrinsic activity and few marginal active spots restrict its electrocatalytic activity. Herein, we successfully constructed a catalyst via a simple hydrothermal method by forming a heterostructure of MoS2 with Cr-doped nickel-iron hydroxide (NiFe LDH) to synthesize a MoS2/NiFeCr LDH catalyst to significantly improve the OER catalytic performance. MoS2 plays a crucial function as an electron transport channel in the MoS2/NiFeCr LDH heterostructure, which increases the electron transport rate. Furthermore, a larger active surface area for NiFeCr LDH is provided by the ultrathin layered structure of MoS2, increasing the number of active sites and encouraging the OER. On the other hand, the introduction of Cr element increased the density of the catalytic center and provided additional Cr-OH active sites, which accelerated the oxygen decomposition reaction. These two factors act synergistically to improve the intrinsic structure of MoS2, increase the number of reactive sites, and dramatically enhance the OER catalytic performance. Excellent OER activity is demonstrated by the MoS2/NiFeCr LDH catalyst, which only needs an overpotential of 224 mV to obtain a current density of 10 mA cm-2 and a Tafel slope of 61 mV dec-1. The catalyst also demonstrated outstanding stability, with its activity practically holding steady after 48 h of testing. This work offers novel ideas for enhancing and designing MoS2-based OER catalysts, and it provides a crucial reference for research in the field of clean energy.

Crystalline/Amorphous Mo-Ni(OH)2/FexNiy(OH)3x+2y hierarchical nanotubes as efficient electrocatalyst for overall water splitting.

The development of efficient bifunctional catalysts for overall water splitting is highly desirable and essential for the advancement of hydrogen technology. In this work, Mo-Ni(OH)2/FexNiy(OH)3x+2y with hierarchical nanotube structure is constructed on flexible carbon cloth (CC) through simple electrochemical deposition and hydrothermal method. The hollow tube-structure is in favor of both exposing active sites and enhancing mass transfer capability. Moreover, the doping of Mo can enhance the electronic conductivity of heterostructures. The interfacial interaction between amorphous and crystal can enhance effectively the charge transfer kinetics across the interface. Therefore, Mo-Ni(OH)2/FexNiy(OH)3x+2y can achieve a low overpotential of 57 mV for hydrogen evolution reaction (HER) and 229 mV for oxygen evolution reaction (OER) at 10 mA·cm-2. In addition, Mo-Ni(OH)2/FexNiy(OH)3x+2y needs a potential of only 1.54 V at 10 mA·cm-2 for overall water splitting, and retains for a long period of time (60 h) reliable. The work will provide a valuable approach to the construction of highly efficient electrocatalysts for overall water splitting.

Sulfidation and NaOH etching in CoFeAl LDH evolved catalysts for an efficient overall water splitting in an alkaline solution.

In this study, a hierarchical interconnected porous metal sulfide heterostructure was synthesized from CoFeAl layered double hydroxides (LDHs) by a two-step hydrothermal process (sulfidation and a NaOH etching process). Among the as-made samples, the CoFeAl-T-NaOH electrode exhibited excellent oxygen and hydrogen evolution reaction catalytic activities with overpotentials of 344 mV and 197 mV at the current density of 100 mA cm-2, respectively. Meanwhile, small Tafel slopes of 57.7 mV dec-1 and 106.5 mV dec-1 for water oxidation and hydrogen evolution were observed for the CoFeAl-T-NaOH, respectively. Serving as both the cathode and anode for overall water splitting, the CoFeAl-T-NaOH electrode reached a current density of 10 mA cm-2 at a cell voltage of 1.65 V with excellent stability. The enhanced electrocatalytic activity could be attributed to: the hierarchical interconnected nanosheet structure facilitating mass transport; the porous structure promoting electrolyte infiltration and reactant transfer; the heterojunction accelerating charge transfer; and the synergistic effect between them. This study offered a new clue for in situ synthesizing porous transition-metal based heterojunction electrocatalysts with a careful tuning of the sequence of sulfuration and alkaline etching to enhance the electrocatalytic performance.

Interface strong-coupled 3D Mo-NiS@Ni-Fe LDH flower-cluster as exceptionally efficient electrocatalyst for water splitting in wide pH range.

It is crucial to create a bifunctional catalyst with high efficiency and low cost for electrochemical water splitting under alkaline and neutral pH conditions. This study investigated the in-situ creation of ultrafine Mo-NiS and NiFe LDH nanosheets as an effective and stable electrocatalyst with a three-dimensional (3D) flower-cluster hierarchical structure (Mo-NiS@NiFe LDH). The strong interfacial connection between Mo-NiS and NiFe LDH enhances the formation of metal higher chemical states in the material, optimizes the electronic structure, increases OH- adsorption capacity improves electron transfer/mass diffusion, and promotes O2/H2 gas release. As a result, at 10 mA cm-2, Mo-NiS@NiFe LDH/NF demonstrates the outstanding bifunctional electrocatalytic activity of just 107 mV (HER, hydrogen evolution reaction) and 184 mV (hydrogen evolution reaction) (OER, oxygen evolution reaction). The catalytic performance is remarkably stable after 72 h of continuous operation in 1 M KOH at high current densities (300 mA cm-2). More interestingly, in the overall water splitting system, the cell voltages for anode and cathode in both alkaline and neutral electrolytes for Mo-NiS@NiFe LDH/NF are only 1.54 V (alkaline) and 2.06 V (neutral) at 10 mA cm-2. These results demonstrated that the bifunctional electrocatalyst design concept is a viable solution for water splitting in both alkaline and neutral systems.

Activatable Lanthanide Nanoprobes with Dye-Sensitized Second Near-Infrared Luminescence for in Vivo Inflammation Imaging.

Lanthanide nanoparticles exhibit unique photophysical properties and thus emerge as promising second near-infrared (NIR-II) optical agents. However, the limited luminescence brightness hampers their construction of activatable NIR-II probes. Herein, we report the synthesis of dye-sensitized lanthanide nanoprobes (NaGdF4:Nd/ICG; indocyanine green (ICG)) and their further development for in vivo activatable imaging of hypochlorite (ClO-). Dye sensitization using ICG not only shifts the optimal doping concentration of Nd3+ from 5 to 20 mol % but also leads to a 5-fold NIR-II enhancement relative to the ICG-free counterpart. Mechanistic studies reveal that such a luminescence enhancement of NaGdF4:Nd at high Nd3+ concentration is ascribed to an alleviated cross-relaxation effect due to the broad absorption of ICG and faster energy transfer process. Taking advantage of dye oxidation, the nanoprobes enable activatable NIR-II imaging of hypochlorous acid (ClO-) in a drug-induced lymphatic inflammation mouse model. This work thus provides a simple, yet effective luminescence enhancement strategy for constructing lanthanide nanoprobes at higher activator doping concentration toward activatable NIR-II molecular imaging.

In-situ growth of 3D hierarchical γ-FeOOH/Ni3S2 heterostructure as high performance electrocatalyst for overall water splitting.

Obtaining efficient, stable, and low-cost electrocatalysts is the key to realizing large-scale water splitting. In this work, three-dimensional (3D) hierarchical γ-iron oxyhydroxide (γ-FeOOH)/Ni3S2 electrocatalyst on Ni foam is constructed for electrochemical overall water splitting. The 3D γ-FeOOH/Ni3S2 heterostructure can effectively enhance active sites and charge transfer capability, also the heterostructure can benefit electronic effect at the interfaces and synergistic effect of multiple components. Therefore, the γ-FeOOH/Ni3S2 exhibits excellent electrocatalytic activity with low overpotentials of 279 mV at 50 mA⋅cm-2 for oxygen evolution reaction and 92 mV at 10 mA⋅cm-2 for hydrogen evolution reaction, respectively. In addition, only a potential of 1.66 V is needed to attain 10 mA⋅cm-2 for the overall water splitting. In particular, the γ-FeOOH/Ni3S2 exhibits long-term stability for 120 h at 10 mA⋅cm-2 without significant degradation. This work provides a valuable idea for obtaining low-cost and high performance bifunctional electrocatalysts for water splitting.

Near-Infrared Nano-Optogenetic Activation of Cancer Immunotherapy via Engineered Bacteria.

Certain anaerobic microbes with the capability to colonize the tumor microenvironment tend to express the heterologous gene in a sustainable manner, which will inevitably compromise the therapeutic efficacy and induce off-tumor toxicity in vivo. To improve the therapeutic precision and controllability of bacteria-based therapeutics, Escherichia coli Nissle 1917 (EcN), engineered to sense blue light and release the encoded flagellin B (flaB), is conjugated with lanthanide upconversion nanoparticles (UCNPs) for near-infrared (NIR) nano-optogenetic cancer immunotherapy. Upon 808 nm photoirradiation, UCNPs emit at the blue region to photoactivate the EcN for secretion of flaB, which subsequently binds to Toll-like receptor 5 expressed on the membrane of macrophages for activating immune response via MyD88-dependent signal pathway. Such synergism leads to significant tumor regression in different tumor models and metastatic tumors with negligible side effects. These studies based on the NIR nano-optogenetic platform highlight the rational of leveraging the optogenetic tools combined with natural propensity of certain bacteria for cancer immunotherapy.

Hierarchical multi-active component yolk-shell nanoreactors as highly active peroxymonosulfate activator for ciprofloxacin degradation.

The reasonable design of the structure and composition of catalysts was essential to improve the catalytic performance of advanced oxidation processes (AOPs). Herein, we reported a simple strategy to synthesize hierarchical Co3O4-C@CoSiOx yolk-shell nanoreactors with multiple active components by using metal-organic frameworks (MOFs). The novel nanoreactors are further used to activate peroxymonosulfate (PMS) for ciprofloxacin (CIP) degradation. The effects of reaction parameters (pH value, co-existing ions, reaction temperature, etc.) on CIP degradation were systematically investigated. Especially, ∼98.2% of CIP was degraded within 17 min under the optimal conditions, together with the low cobalt leaching and excellent reusability. The appreciable catalytic performance improvement might be due to the synergistic effect of the structure and component design: (1) the hierarchical yolk-shell structure endowed the catalyst with high surface area (∼232.47 m2/g) and fully exposed active sites; (2) abundant highly active ≡Co-OH+ were formed on the surface of CoSiOx; (3) the presence of oxygen vacancies and nitrogen-doped carbon promoted the decomposition of PMS through a non-radical process. The results revealed both the radical (SO4∙-, ∙OH and O2∙-) and non-radical (1O2 and direct charge transfer) should be responsible for the CIP degradation. Moreover, the possible degradation pathways of CIP were proposed through the identification of intermediates using LC-MS/MS techniques and density functional theory (DFT) calculation. Our work highlights that multi-component catalysts derived from MOFs with novel structure have broad application prospects in AOPs.

Engineering interfacial coupling between 3D net-like Ni3(VO4)2 ultrathin nanosheets and MoS2 on carbon fiber cloth for boostinghydrogen evolution reaction.

The use of cheap and efficient electrocatalyst for the production of hydrogen is the key to solving the current energy crisis. Herein, we used a two-step hydrothermal process to fabricate noble-metal-free 3D net-like Ni3(VO4)2 ultrathin nanosheets coupled with MoS2@CFC interface. Unlike the traditional two-dimensional composite materials, Ni3(VO4)2 ultrathin nanosheets intersect with MoS2 nanosheets grown on CFC in a 3D net-like structure (Ni3(VO4)2/MoS2@CFC). Due to the mutual combination of structures and the interfacial coupling cooperation effect between Ni3(VO4)2 nanosheet and MoS2@CFC, the catalytically active area was expanded, and the intrinsic activity toward HER was significantly improved. Ni3(VO4)2/MoS2@CFC showed high activity at the industrial temperature (75 °C), with an overpotential of 77 mV (10 mA/cm2) and a 65 mV/dec Tafel slope. This material showed good stability at 0.5 M H2SO4. This work provides a heterostructure scheme for the construction of a novel noble metal-free electrocatalyst to promote hydrogen evolution reaction.

Artificial Atomic Vacancies Tailor Near-Infrared II Excited Multiplexing Upconversion in Core-Shell Lanthanide Nanoparticles.

Epitaxial growth of an inert shell around the optical active lanthanide upconversion nanoparticles (UCNPs) is a general strategy to enhance their brightness. Yet, its potential as a tool in multiplexing emission tailoring has rarely been reported. Here, by developing the atomic vacancies into color selectivity actuators, we present an efficient strategy to achieve inert-shell-modulated multiplexing upconversion in 1540 nm activated UCNPs. Artificially generated fluoride atomic vacancies, owing to the decreased NaOH/NH4F dosage during shell growth, reduce the coordination number of Y-F and lattice densities in the inert shell, leading to the core-engineered shell nanoparticles with distinctive emission profiles. The multicolor tailoring is independent of shell thickness and can be readily applied to Lu3+/Gd3+-based shells. The upconversion emission can be exploited to visualize in security decoding and in vivo multiplexing bioimaging. This method of regulating atomic vacancies based on the inert-shell engineering opens new insights of upconversion modulation in core-shell lanthanide nanostructures.

Progress in Electrocatalytic Hydrogen Evolution Based on Monolayer Molybdenum Disulfide.

Energy and environmental issues raise higher demands on the development of a sustainable energy system, and the electrocatalytic hydrogen evolution is one of the most important ways to realize this goal. Two-dimensional (2D) materials represented by molybdenum disulfide (MoS2) have been widely investigated as an efficient electrocatalyst for the hydrogen evolution. However, there are still some shortcomings to restrict the efficiency of MoS2 electrocatalyst, such as the limited numbers of active sites, lower intrinsic catalytic activity and poor interlayer conductivity. In this review, the application of monolayer MoS2 and its composites with 0D, 1D, and 2D nanomaterials in the electrocatalytic hydrogen evolution were discussed. On the basis of optimizing the composition and structure, the numbers of active sites, intrinsic catalytic activity, and interlayer conductivity could be significantly enhanced. In the future, the study would focus on the structure, active site, and interface characteristics, as well as the structure-activity relationship and synergetic effect. Then, the enhanced electrocatalytic activity of monolayer MoS2 can be achieved at the macro, nano and atomic levels, respectively. This review provides a new idea for the structural design of two-dimensional electrocatalytic materials. Meanwhile, it is of great significance to promote the study of the structure-activity relationship and mechanism in catalytic reactions.

In situ growth of metallic Ag0 intercalated CoAl layered double hydroxides as efficient electrocatalysts for the oxygen reduction reaction in alkaline solutions.

Metallic Ag0 intercalated CoAl-layered double hydroxides (CoAl LDHs) have been successfully synthesized in situ through a simple redox process with ethylene glycol (EG) and triethanolamine (TEOA). The Ag(CN)2- anion-exchanged precursor was reduced by EG to form metallic Ag0. Furthermore, the effect of TEOA on confining the particle size of Ag0 was demonstrated. The oxygen reduction reaction (ORR) property of metallic Ag0 intercalated CoAl LDHs was examined in alkaline aqueous solution. A typical sample synthesized by the addition of TEOA for 180 min exhibited excellent ORR catalytic activity with a high current density of 5.5 mA cm-2 at 0.2 V (vs. a reversible hydrogen electrode (RHE)) and good stability. Koutecky-Levich (K-L) calculations and rotating ring-disk electrode (RRDE) measurements further revealed that the ORR of the as-prepared catalyst proceeded mainly via an almost ideal four-electron transfer process. The enhanced electrocatalytic activity was ascribed to the intercalated Ag0, confined nanoparticle size and the expanded interlayer space, which effectively facilitate the reactant transfer and electron migration.

Fabrication of Hierarchical ZnO@NiO Core-Shell Heterostructures for Improved Photocatalytic Performance.

ZnO@NiO core-shell heterostructures with high photocatalytic efficiency and reusability were prepared via electrochemical deposition on carbon fiber cloth substrates. Their photocatalytic properties were investigated by measuring the degradation of rhodamine B and methyl orange (MO) under ultraviolet light irradiation. The photodegradation efficiency of the ZnO@NiO heterostructures toward both dyes was better than those of the pure ZnO nanorods and NiO nanosheets. The higher performance could be attributed to the formation of p-n heterojunction between ZnO and NiO. Especially, the ZnO@NiO heterostructure formed upon deposition of NiO for 10 min degraded 95% of MO under ultraviolet light irradiation for 180 min. The high photodegradation efficiency of the ZnO@NiO heterostructures was also attributed to the high separation efficiency of photogenerated carriers, as confirmed by the higher photocurrent of the ZnO@NiO heterostructures (eightfold) when compared with that of the pure ZnO nanorods. Moreover, the high photodegradation efficiency of the ZnO@NiO heterostructures was maintained over three successive degradation experiments and decreased to 90% after the third cycle.

Synergizing Upconversion Nanophotosensitizers with Hyperbaric Oxygen to Remodel the Extracellular Matrix for Enhanced Photodynamic Cancer Therapy.

Photodynamic therapy (PDT) holds great promise as a noninvasive and selective cancer therapeutic treatment in preclinical research and clinical practice; however, it has limited efficacy in the ablation of deep-seated tumor because of hypoxia-associated circumstance and poor penetration of photosensitizers to cancer cells away from the blood vessels. To tackle the obstacles, we propose a therapeutic strategy that synergizes upconversion nanophotosensitizers (UNPSs) with hyperbaric oxygen (HBO) to remodel the extracellular matrix for enhanced photodynamic cancer therapy. The UNPSs are designed to have an Nd3+-sensitized sandwiched structure, wherein the upconversion core serves as light transducers to transfer energy to the neighboring photosensitizers to produce reactive oxygen species (ROS). With HBO, photodynamic process can generate abundant ROS in the intrinsically hypoxic tumor. It is revealed for the first time that HBO-assisted PDT decomposes collagen in the extracellular matrix of tumor and thus facilitates the diffusion of oxygen and penetration of UNPSs into the deeper area of tumor. Such a synergic effect eventually results in a significantly enhanced therapeutic efficacy at a low laser power density as compared with that using UNPSs alone. In view of its good biosafety, the HBO-assisted and UNPSs-mediated PDT provides new possibilities for treatment of solid tumors.

Enhanced Efficiency of Dye-Sensitized Solar Cells Benefited from Graphene Modified by Ag Nanoparticles.

In this paper, graphene modified by Ag nanoparticles was successfully applied into dye sensitized solar cells. The morphologies and compositions of graphene and graphene-Ag nanoparticles were characterized by scanning electron microscope and energy dispersive X-ray spectroscopy. The optical and electrical properties were evaluated by UV-vis-NIR absorption spectroscopy, electrochemical impedance spectroscopy and current-voltage curve. The results indicated that the incorporation of graphene or graphene-Ag nanoparticles can improve the light absorption and decrease the charge recombination. The solar cells with graphene-Ag nanoparticles exhibited short-circuit current density of 14.34 mA cm-2, open-circuit voltage of 709 mV and conversion efficiency of 6.01%, which were higher than those of DSSCs with graphene or pure TiO2.

Surface/Interfacial Structure and Chemistry of High-Energy Nickel-Rich Layered Oxide Cathodes: Advances and Perspectives.

The urgent prerequisites of high energy-density and superior electrochemical properties have been the main inspiration for the advancement of cathode materials in lithium-ion batteries (LIBs) in the last two decades. Nickel-rich layered transition-metal oxides with large reversible capacity as well as high operating voltage are considered as the most promising candidate for next-generation LIBs. Nonetheless, the poor long-term cycle-life and inferior thermal stability have limited their broadly practical applications. In the research of LIBs, it is observed that surface/interfacial structure and chemistry play significant roles in the performance of cathode cycling. This is due to the fact that they are basically responsible for the reversibility of Li+ intercalation/deintercalation chemistries while dictating the kinetics of the general cell reactions. In this Review, the surface/interfacial structure and chemistry of nickel-rich layered cathodes involving structural defects, redox mechanisms, structural evolutions, side-reactions among others are initially demonstrated. Recent advancements in stabilizing the surface/interfacial structure and chemistry of nickel-rich cathodes by surface modification, core-shell/concentration-gradient structure, foreign-ion substitution, hybrid surface, and electrolyte additive are presented. Then lastly, the remaining challenges such as the fundamental studies and commercialized applications, as well as the future research directions are discussed.

One-pot Synthesis of CdS Irregular Nanospheres Hybridized with Oxygen-Incorporated Defect-Rich MoS2 Ultrathin Nanosheets for Efficient Photocatalytic Hydrogen Evolution.

Robust and highly active photocatalysts, CdS@MoS2, for hydrogen evolution were successfully fabricated by one-step growth of oxygen-incorporated defect-rich MoS2 ultrathin nanosheets on the surfaces of CdS with irregular fissures. Under optimized experimental conditions, the CdS@MoS2 displayed a quantum yield of ∼24.2% at 420 nm and the maximum H2 generation rate of ∼17203.7 umol/g/h using Na2S-Na2SO3 as sacrificial agents (λ ≥ 420 nm), which is ∼47.3 and 14.7 times higher than CdS (∼363.8 µmol/g/h) and 3 wt % Pt/CdS (∼1173.2 µmol/g/h), respectively, and far exceeds all previous hydrogen evolution reaction photocatalysts with MoS2 as co-catalysts using Na2S-Na2SO3 as sacrificial agents. Large volumes of hydrogen bubbles were generated within only 2 s as the photocatalysis started, as demonstrated by the photocatalytic video. The high hydrogen evolution activity is attributed to several merits: (1) the intimate heterojunctions formed between the MoS2 and CdS can effectively enhance the charge transfer ability and retard the recombination of electron-hole pairs; and (2) the defects in the MoS2 provide additional active S atoms on the exposed edge sites, and the incorporation of O reduces the energy barrier for H2 evolution and increases the electric conductivity of the MoS2. Considering its low cost and high efficiency, this highly efficient hybrid photocatalysts would have great potential in energy-generation and environment-restoration fields.

One-pot hydrothermal synthesis of CdS decorated CuS microflower-like structures for enhanced photocatalytic properties.

CdS decorated CuS structures have been controllably synthesized through a one-pot hydrothermal method. The morphologies and compositions of the as-prepared samples could be concurrently well controlled by simply tuning the amount of CdCl2 and thiourea. Using this strategy, the morphology of the products experienced from messy to flower-like morphologies with multiple porous densities, together with the phase evolution from pure CuS to the CdS/CuS composites. Serving as a photocatalyst, the samples synthesized with the addition of 1 mmol cadmium chloride and 3 mmol thiourea during synthetic process, showed the best photocatalytic activity, which could reach a maximum photocatalytic efficiency of 93% for methyl orange (MO) photodegradation after 150 min. The possible mechanism for the high photocatalytic efficiency of the sample was proposed by investigating the composition, surface area, structure, and morphology before and after photocatalytic reaction.