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Constructing efficient and cost‐effective photocatalysts are highly desirable for photocatalytic hydrogen evolution. Herein, we prepare a unique 2D‐2D architecture photocatalyst composed of CoP and ZnIn2S4 (ZIS) nanosheets through electrostatic self‐assembly method. The constructed 2D‐2D CoP/ZIS exhibit a remarkably enhanced photocatalytic performance with hydrogen production rate of 8.775 mmol g−1 h−1, and this value is much higher than ZIS and most of other ZIS‐based nanohybrids. Additionally, the nanohybrids possess excellent stability with 96.3% of initial activity remaining after 24 hours of testing. These satisfactory results are attributed to the large/intimate contact interface and the photo/electro‐chemical properties of ZIS and CoP, which improves light absorption, facilitates photoelectron transport and suppresses charge recombination. This work not only demonstrates ZIS nanosheet can serve as a versatile and effective platform supporting non‐noble metal nanosheets to boost their photocatalytic performance, but also offers a general and simple electrostatic self‐assembly method to design 2D‐2D‐based heterostructures for hydrogen conversion from water splitting. [ABSTRACT FROM AUTHOR]

Ternary composite of biomass porous carbon/SnO2/Pt was prepared by a facile two‐step method consisting of the hydrothermal process and the impregnation‐chemical reduction procedure. The SEM and TEM revealed that particles of SnO2 deposited on the surface of porous carbon (PC) and formed an intermediate layer, which facilitated Pt nanoparticles (around 3–4 nm) to deposit uniformly and firmly on the surface. The ternary composite catalyst of Pt‐SnO2/PC exhibited significantly enhanced performance during the catalytic reduction of 4‐nitrophenol to 4‐aminophenol, and the reaction could completely finished within 80 seconds at room temperature, which apparent rate constant (Ka=71 × 10−3 s−1) was approximately 36 times higher than that of Pt/PC with the same Pt loading. The hybrid catalyst also presented a good stability and the catalytic activity could maintain above 90% even after eighth recycling of reaction. Due to its unique structure and high catalytic performance, ternary composite of Pt‐SnO2/PC has great potential in catalysis applications. [ABSTRACT FROM AUTHOR]

Laccase was immobilized in polyvinyl alcohol beads containing halloysite nanotubes (PVA/HNTs) to improve the stability and reusability of enzyme. The porous structure of PVA/HNTs beads facilitates the entrapment of enzyme and prevents the leaching of immobilized laccase as well. Halloysite nanotubes act as bridge to connect the adjacent pores, facilitating the electron transfer and enhancing the mechanical properties. PVA/HNTs beads have high laccase immobilization capacity (237.02 mg/g) and activity recovery yield (79.15%), indicating it can be used as potential support for laccase immobilization. Compared with free laccase, the immobilized laccase on hybrid beads exhibits enhanced pH tolerance (even at pH 8.0), good thermal stability (57.5% of the initial activity can be maintained at 75 °C), and excellent storage stability (81.17% of enzyme activity could be retained after storage at 4 °C for 5 weeks compared with that for free enzyme of 60%). Also, the removal efficiency for reactive blue can reach as high as 93.41% in the presence of redox mediator 2,2-azinobis(3-ethylbenzthiazoline-6-sulfonate), in which adsorption and degradation exist simultaneously. The remarkable pH tolerance, thermal and storage stability, and reuse ability imply potential application of porous PVA/HNTs immobilized enzyme in environmental fields.

The matching algorithm based on mutual information, which has the advantages of high speed, good automation and superion accuracy, is widely used in medical image registration. In this paper are presented the basic conception of mutual information, the transform model, the insert value algorithm, the optimization algorithm and the strategy in computing mutual information. Furthermore, we introduce some efficient methods for solving the problems in registration technique based on mutual information, and look forward to the future research work.