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The hollow microsphere structure materials binary disulfide Co1-xCuxS2 (x = 0, 0.05, 0.10, 0.15, 0.20, 0.25) were synthesized by hydrothermal method with cobalt sulfate, copper sulfate, and sodium thiosulfate. The structure, morphology, and composition of Co1-xCuxS2 were characterized by X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), and energy dispersive spectrometer (EDS). The influence of cobalt and copper content in Co1-xCuxS2 cathode material on the discharge performance of the cell was investigated. The experimental results show that the Co0.95Cu0.05S2 sample possesses the largest number of hollow microspheres, the internal resistance of the cell was lower and the specific capacity of the cell is higher. The results of constant current discharge showed that the optimal composition Co0.95Cu0.05S2 exhibits an ultra-high specific capacity of 531.8 mAh g-1 at 450℃ and the current density of 100 mA·cm-2 with the cut-off voltage of 1.5V. The best discharge temperature of Co0.95Cu0.05S2 was 450℃.

The innovative design of Fe2TiO5 nanorods and the loading of NiMoO4/CoMoO4 nanosheet cocatalyst greatly improved the performance for oxidation of water.

An electrocatalyst achieved rational tuning of defects and lattice distortions and exhibited robust stability in alkaline electrolytes.

An enhanced OER catalyst based on Fe doped CePO4 exhibits higher turnover frequency, more active sites and more oxygen vacancies than CePO4.

The synthesis of polar functionalized cyclic olefin copolymers (COCs) from the coordination copolymerization of norbornene (NB) and polar monomers catalyzed by late transition metal catalysts has been a recent research hotspot. However, few catalysts have achieved efficient copolymerization with commercial vinyl-type polar monomers, such as methyl acrylate (MA). In this contribution, nickel complexes bearing 2-(diarylphosphino)-N-phenylbenzenamine ligands were synthesized and applied as pre-catalysts to catalyze the (co)polymerization of norbornene. Upon the activation of methylaluminoxane (MAO), these nickel catalysts were active for norbornene polymerization with the highest activity achieved being 3.6 × 106 g mol−1 h−1 and the highest number average molecular weight (Mn) of polynorbornene (PNB) reaching 27.4 × 105 g mol−1. Moreover, these nickel catalysts also promoted the copolymerization of norbornene and MA to furnish high-molecular-weight NB/MA copolymers (Mn up to 6.20 × 104 g mol−1) with reasonable MA contents (3.07−5.90 mol%). The molecular weight of PNB and NB/MA copolymers obtained by the present nickel catalysts are remarkably higher than those of the (co)polymers from our previous reported dimethyl substituted phosphinobenzenamine nickel catalyst, suggesting significant progress in this field.

Electrocatalytic hydrogen evolution reaction (HER) in alkaline media is important for hydrogen economy but suffers from sluggish reaction kinetics due to a large water dissociation energy barrier. Herein, Pt

Structural engineering of highly efficient electrocatalysts based on 2D transition metal dichalcogenides (TMDs) for hydrogen evolution reaction (HER) is of great significance for sustainable energy conversion processes. Herein, a novel basal-plane engineering of 2D colloidal VSe2 nanosheets has been developed for highly enhanced HER performance via a synergistic combination of atmosphere plasma (AP) treatment and Co basal-plane doping. Systematic experiments and theoretical calculations show that the AP treatment not only efficiently removes the organic ligands, but also introduces defects and cracks as more active sites on the basal plane; while the Co basal-plane doping and defects further optimize Gibbs free energy of hydrogen adsorbed on the Se sites. Such AP treated 5 % Co doped VSe2 electrocatalyst exhibits onset overpotential of only 160 mV, Tafel slope of 42 mV/decade and turnover frequency (TOF) of 6.4 S−1 at 260 mV, comparable to the most active TMDs electrocatalysts. This work provides fresh insights into the utilization of “clean surface”, defects/cracks and heteroatom doping on basal plane of 2D nanosheets for catalytic application.

Noble-metal-free composites with good photocatalytic property are of great interest. Here, CeO2 nanorods composites loaded with amorphous Fe(OH)3 cocatalyst were designed and prepared via a secondary water bath at 100 °C. The as-synthesized CeO2 /amorphous Fe(OH)3 composites exhibited superior light photocatalytic activities compared to pure CeO2 , especially the sample with a loading time of 60 min. The photocatalytic oxygen generation rate could reach to 357.2 μmol h-1 g-1 , and the average apparent quantum yield (AQY) was 24.67 %, which was a 5.5-fold increase compared to the CeO2 sample. The improvement of photocatalytic performance could be ascribed to three main reasons: First, loading the amorphous Fe(OH)3 enlarged the specific surface area and passivated the surface of the pristine CeO2 . Second, the amorphous Fe(OH)3 ,which acted as a cocatalyst, provided many active sites, and reduced the reaction activation energy. Thirdly, the maximum interface with intimate contact between CeO2 and amorphous Fe(OH)3 cocatalyst accelerated the photogenerated charge separation efficiency and thus improved the photocatalytic performance of CeO2 in photocatalytic water oxidation.

Design of hollow nanostructure and controllable phase of mixed metal oxides for improving performance in supercapacitor applications is highly desirable. Here we demonstrate the rational design and synthesis of Mn 3-x Fe x O 4 hollow nanostructures for supercapacitor applications. Owing to high porosity and the specific surface area that provides more active sites for electrochemical reactions, the electrochemical performance of Mn 3-x Fe x O 4 hollow nanostructure substantially enhances comparing with pristine Mn 3 O 4 . Particularly, in 1.0 M KOH electrolyte, Mn 0.16 Fe 2.84 O 4 with a typical diameter of 20 nm exhibits excellent specific capacitance of 2675, 2320, 1662, 987 Fg -1 at current densities of 1, 2, 5, 10 Ag -1 , respectively, which is significantly superior to those of other transition metal oxides. Besides, an asymmetric supercapacitor is assembled by using Mn 0.16 Fe 2.84 O 4 and activated carbon as a positive and a negative electrode, respectively. Electrochemical results indicate a high energy density of 42 Wh kg -1 at a power density of 0.75 kW kg -1 , which makes this hollow nanostructure a highly promising electrode for achieving high-performance next-generation supercapacitors.

For photoelectrochemical (PEC) water splitting, constructing heterojunctions and loading co-catalysts are effective means to realizing sufficient light absorption, effective photogenerated carrier separation and fast charge transport. However, during implementation, the PEC performance of the catalyst is affected by both parasitic light absorption and reflection and the change in energy band structure due to the creation of new interfaces. Herein, in order to minimize the effect of recombination of photogenerated electron-hole pairs on the catalyst PEC performance due to the nascent interface arising from the co-catalyst compounding, WO

Noble metal Pt as an efficient cocatalyst is widely utilized in the photocatalytic hydrogen (H2) evolution field while its application is restricted by high price and scarcity. Herein, a feasible strategy for depositing a non-noble bimetallic cocatalyst on a ZnIn2S4 surface has been put forward. The low-cost and earth-abundant CuNi bimetal cocatalyst was deposited via a simple one-step photoreduction method. In this novel photocatalytic system, CuNi bimetal served as dual active sites which can inhibit the recombination of charge carriers on ZnIn2S4. Compared with single Cu or Ni deposited ZnIn2S4 samples, CuNi bimetal decorated samples showed a significant enhancement in hydrogen evolution activity. Meanwhile, 12% Cu2Ni1–ZIS realized the highest hydrogen generation rate (7825 μmol h−1 g−1, AQE = 30.19%, λ > 420 nm). The enhanced photocatalytic performance can be attributed to the spillover effect of H atoms from Ni to Cu and the synergistic effect between the metals. This work provides a novel strategy for optimizing the H2 evolution performance of a ZnIn2S4-based photocatalyst by utilizing a non-noble bimetallic cocatalyst as dual active sites.

Perovskite oxides (ABO3) with flexible structural and chemical properties have attracted wide attention in electrocatalytic water splitting. However, their poor intrinsic activity and unsuitable adsorption energy for oxygenated species greatly limit their application. Heteroatom doping has been demonstrated to be an efficient strategy to modulate the electronic structure of the host and thus improve its OER properties. And FeOOH can effectively adsorb OER intermediates and provide abundant active sites for the OER. Herein, a novel hybrid OER electrocatalyst consisting of Ni-doped LaFeO3 with a porous structure combined with ultra-thin amorphous FeOOH nanosheets (NiFe–LFO) is successfully designed and prepared via a simple two-step hydrothermal method. The prepared catalyst exhibited an extremely low overpotential of 186 mV at 10 mA cm−2. Density functional theory calculations reveal that the strong electronic interactions at the interface of the composite play a crucial role in the enhancement of catalytic performance. And the Ni2+ doping effectively modulates the electronic structure of LFO and enhances the electron transport at the interface of LFO and FeOOH, resulting in an elevated d-band centre of FeOOH, thus leading to high OER activity. This work provides an approach for designing other advanced OER electrocatalysts for sustainable energy devices.

The low separation efficiency and high recombination of photogenerated charge carriers are the main challenges in the development of effective photocatalytic materials. The construction of two-dimensional (2D) nanosheet heterostructures with a co-catalyst would accelerate the photogenerated charge transfer and increase the number of active sites for H2 evolution, which may be an effective strategy to improve charge separation efficiency and reduce recombination. In this research, novel 2D/2D MoSe2/ZnIn2S4 complex heterojunctions have been successfully synthesized by a secondary hydrothermal method. 2D ZnIn2S4 nanosheets were firstly prepared and then 2D MoSe2 nanosheets were formed on the ZnIn2S4. As a cocatalyst, the 2D MoSe2 nanosheets could provide abundant active sites reducing the overpotential and the activation energy for water reduction. By synergic effects, the 2D/2D heterojunction formed between MoSe2 and ZnIn2S4 can provide a large and intimate contact area, which accelerates the photogenerated charge separation and transfer resulting in high photocatalytic activity. It has been demonstrated that the H2 evolution rate using 10%MoSe2/ZnIn2S4 as the catalyst is 10 times higher than that using ZnIn2S4 alone as the catalyst, which is 1226 μmol g−1 h−1 and 116 μmol g−1 h−1, respectively, in water splitting under visible light irradiation. This work provides more insights into the rational design and synthesis of 2D heterostructures by using 2D materials as co-catalysts.

Fully utilizing the visible light and lowering the economic costs are the toughest challenges of photocatalytic water splitting. To address these issues, a non-noble metal photocatalyst, (CuIn)xZn2(1−x)S2 solid solution with an adjustable band gap by modifying its composition, was synthesized. In addition, amorphous molybdenum sulfide (a-MoSx) was compounded as a co-catalyst on the surface of the solid solution. Compared with crystalline molybdenum sulfide (MoS2), a-MoSx can provide more active sites and reduce the activation energy of hydrogen evolution reactions more effectively. The (CuIn)0.2Zn1.6S2 (CIZS) photocatalyst loaded with 3 wt% a-MoSx exhibited the best photocatalytic performance with a hydrogen evolution rate of 2100 μmol g−1 h−1.

Nanostructured lipid carriers (NLC) have become a research hotspot, wherein cancer-targeting effects are enhanced and side effects of chemotherapy are overcome. Usually, accelerated blood clearance...

Photocatalytic water splitting for hydrogen evolution is one of the most promising methods to mitigate environmental and energy-related issues. In this study, manganese cadmium sulfide (Mn