Shanghai Institute of Technology

Inorganic hollow spheres have attracted considerable interest due to their singular properties and wide range of potential applications. In this critical review, we provide a comprehensive overview of the preparation and applications of inorganic hollow spheres. We first discuss the syntheses of inorganic hollow spheres by use of polymers, inorganic nonmetals, metal-based hard templates, small-molecule emulsion, surfactant micelle-based soft-templates, and the template-free approach. For each method, a critical comment is given based on our knowledge and related research experience. We go on to discuss some important applications of inorganic hollow spheres in 0D, 2D, and 3D arrays. We conclude this review with some perspectives on the future research and development of inorganic hollow spheres (235 references).

Combining the advantages from both porous materials and graphene, porous graphene materials have attracted vast interests due to their large surface areas, unique porous structures, diversified compositions and excellent electronic conductivity. These unordinary features enable porous graphene materials to serve as key components in high-performance electrochemical energy storage and conversion devices such as lithium ion batteries, supercapacitors, and fuel cells. This progress report summarizes the typical fabrication methods for porous graphene materials with micro-, meso-, and macro-porous structures. The structure-property relationships of these materials and their application in advanced electrochemical devices are also discussed.

Although the concept of Janus particles was raised in the early 1990s, the related research has not attracted considerable interest until recently due to the special properties and applications of these colloidal particles as well as the advances in new fabrications. Janus particles can be divided into three categories: polymeric, inorganic, and polymeric-inorganic, and each kind of Janus particles can be spherical, dumbbell-like, half raspberry-like, cylindrical, disk-like, or any of a variety of other shapes. Different Janus particles may share common preparation principles or require specific fabrication processes, and may have different assembly behaviours and properties. This critical review discusses the main fabrication methods of the three kinds of Janus particles, and then highlights the important properties and applications of these Janus particles developed in recent years, and finally proposes some perspectives on the future of Janus particle research and development.

Thermoelectric generators (TEGs) can directly convert waste heat into electrical power. In the last few decades, most research on thermoelectrics has focused on inorganic bulk thermoelectric materials and corresponding devices, and their thermoelectric properties have been significantly improved. An emerging topic is flexible devices, where the use of bulk inorganic materials is precluded by their inherent rigidity. The purpose of this paper is to review the research progress on flexible thermoelectric materials and generators, including theoretical principles for TEGs, conducting polymer TE materials, nanocomposites comprised of inorganic nanostructures in polymer matrices and fully inorganic flexible TE materials in nanostructured thin films. Approaches for flexible TEGs and components are reviewed, and remaining challenges discussed.

The Tafel equation is of fundamental importance in electrochemical kinetics, formulating a quantitative relation between the current and the applied electrochemical potential. The recent years have seen the rapid expansion and development in the application of first-principles density functional theory (DFT) simulation on electrocatalytic reactions that occur at the solid–liquid interface. This article reviews the current theoretical methods for electrochemistry modeling, in particular, those for the direct computation of Tafel kinetics of electrocatalytic reactions on surfaces based on DFT calculations. Representative reactions, namely, hydrogen evolution and oxygen evolution reactions, are selected to illustrate how the theoretical methods are applied to compute quantitatively the kinetics of multiple-step electrochemical reactions. We summarize in detail the computation procedure based on the first-principles periodic continuum solvation method for obtaining the charge transfer coefficient (CTC) and deducing the potential-dependent reaction rate. The theoretical results on the Tafel kinetics of electrochemical reactions are generalized and discussed.

Abstract 2D transition metal carbides and/or nitrides (MXenes), by virtue of high electrical conductivity, abundant surface functional groups and excellent dispersion in various solvents, are attracting increasing attention and showing competitive performance in energy storage and conversion applications. However, like other 2D materials, MXene nanosheets incline to stack together via van der Waals interactions, which lead to limited number of active sites, sluggish ionic kinetics, and finally ordinary performance of MXene materials/devices. Constructing 2D MXene nanosheets into 3D architectures has been proven to be an effective strategy to reduce restacking, thus providing larger specific surface area, higher porosity, and shorter ion and mass transport distance over normal 1D and 2D structures. In this review, the commonly used strategies for manufacturing 3D MXene architectures (3D MXenes and 3D MXene‐based composites) are summarized, such as template, assembly, 3D printing, and other methods. Special attention is also given to the structure–property relationships of 3D MXene architectures and their applications in electrochemical energy storage and conversion, including supercapacitors, rechargeable batteries, and electrocatalysis. Finally, the authors propose a brief perspective on future opportunities and challenges for 3D MXene architectures/devices.

Abstract Photochemical solution-phase reactions have been widely applied for the syntheses of nanocrystals. In particular, tuning of the nucleation and growth of solids has been a major area of focus. Here we demonstrate a facile approach to generate atomically dispersed platinum via photochemical reduction of frozen chloroplatinic acid solution using ultraviolet light. Using this iced-photochemical reduction, the aggregation of atoms is prevented, and single atoms are successfully stabilized. The platinum atoms are deposited on various substrates, including mesoporous carbon, graphene, carbon nanotubes, titanium dioxide nanoparticles, and zinc oxide nanowires. The atomically dispersed platinum on mesoporous carbon exhibits efficient catalytic activity for the electrochemical hydrogen evolution reaction, with an overpotential of only 65 mV at a current density of 100 mA cm −2 and long-time durability (>10 h), superior to state-of-the-art platinum/carbon. This iced-photochemical reduction may be extended to other single atoms, for example gold and silver, as demonstrated in this study.

Considerable knowledge has been accumulated on the lactic acid bacteria (LAB) that affect the aroma and flavour of yogurt. This review focuses on the role of LAB in the production of flavour compounds during yogurt fermentation. The biochemical processes of flavour compound formation by LAB including glycolysis, proteolysis, and lipolysis are summarised, with some key compounds described in detail. The flavour-related activities of LAB mostly depend on the species used for yogurt fermentation, and some strategies have been developed to obtain more control of the flavour-forming process. Metabolic engineering can be a powerful tool to reroute the metabolic flux towards the efficient accumulation of the desired flavour compounds with the knowledge of the complex network of flavour-forming pathways and the availability of genetic tools. Further progress made in the omics-based techniques and the use of systems biology approaches are needed to fully understand, control, and steer flavour formation in yogurt fermentation processes.

Abstract The rational design of magnetic composites has great potential for electromagnetic (EM) absorption, particularly in the low‐frequency range of 2–8 GHz. However, the scalable synthesis of such magnetic absorbers with both high magnetic content and good dispersity remains challenging. In this study, a confined diffusion strategy is proposed to fabricate functional magnetic‐carbon hollow microspheres. Driven by the ferromagnetic enhanced Kirkendall diffusion effect, the in situ alloying of FeCo nanoparticles is tightly confined in carbon shells, effectively inhibiting magnetic agglomeration. Moreover, the core–shell FeCo–carbon nano‐units further assemble into dispersive microscale magnetic‐carbon Janus bulges on both the inner and outer surfaces of the hollow microsphere. The optimized hollow FeCo@C microspheres exhibit excellent low‐frequency EM wave absorption performance: the minimum reflection loss ( RL min ) is −35.9 dB, and the absorption bandwidth covers almost the entire C‐band. Systematic investigation reveals that the large size of the magnetic‐carbon integration, high–density confined magnetic units, and strong magnetic coupling are essential for enhancing the magnetic loss dissipation of low‐frequency EM waves. This study provides a novel strategy for fabricating advanced EM wave absorbers and significant inspiration for investigating the magnetic attenuation mechanism at low frequency.

Visible‐infrared dual‐modal light harvesting is crucial for various optoelectronic devices, particularly for solar cells and photodetectors. For the first time, this study reports on large 25 cm 3 ‐volume all‐inorganic perovskite CsPbBr 3 single crystal (SC) with an emphasis on the observed visible‐infrared dual‐modal light harvesting and sensing as demonstrated by the high‐performance visible‐infrared dual‐modal photodetectors. First, ultralarge 25 cm 3 ‐volume CsPbBr 3 SC ingots with trapping state density as low as of 1 × 10 9 cm −3 have been achieved by a modified Bridgman growth method. The volume reported here is the largest CsPbX 3 (X = Cl, Br, I) all‐inorganic perovskite system up to now, and the SC can be facilely cut into SC wafers with a diameter of 25 mm for various optoelectronic devices. Furthermore, these CsPbBr 3 SCs exhibit a visible absorbance coefficient, a near‐infrared (IR) two‐phonon absorption coefficient, a carrier diffusion length, and a mobility as high as of 10 5 cm −1 , 3.7 cm per Goeppert‐Mayer (GM), 10 µm and 2000 cm 2 V −1 s −1 , respectively. These merits match well to the requirements of high‐performance Vis‐IR dual‐modal light harvesting optoelectronic devices, which has been demonstrated by the CsPbBr 3 SC photodetectors operated under the irradiation of both visible and IR light sources with light on/off ratio higher than 10 3 . These results demonstrate the CsPbBr 3 SCs with high visible‐infrared dual‐modal light harvesting capability and excellent electrical transporting properties have a huge potential in various optoelectronic devices, such as solar cells, photodetectors, and lasers.

We designed and prepared a novel alginate/reduced graphene oxide double-network hydrogel and investigated its mechanical properties, stability and adsorption capacity in comparison with a single network.

Low cost and high conductivity make copper (Cu) nanowire (NW) electrodes an attractive material to construct flexible and stretchable electronic skins, displays, organic light-emitting diodes (OLEDs), solar cells, and electrochromic windows. However, the vulnerabilities that Cu NW electrodes have to oxidation, bending, and stretching still present great challenges. This work demonstrates a new Cu@Cu4Ni NW conductive elastomer composite with ultrahigh stability for the first time. Cu@Cu4Ni NWs, facilely synthesized through a one-pot method, have highly crystalline alloyed shells, clear and abrupt interfaces, lengths more than 50 μm, and smooth surfaces. These virtues provide the NW-elastomer composites with a low resistance of 62.4 ohm/sq at 80% transparency, which is even better than the commercial ITO/PET flexible electrodes. In addition, the fluctuation amplitude of resistance is within 2 ohm/sq within 30 days, meaning that at ΔR/R0 = 1, the actual lifetime is estimated to be more than 1200 days. Neither the conductivity nor the performances of OLED with elastomers as conductive circuits show evident degradation during 600 cycles of bending, stretching, and twisting tests. These high-performance and extremely stable NW elastomeric electrodes could endow great chances for transparent, flexible, stretchable, and wearable electronic and optoelectronic devices.

The aroma profile of oolong tea infusions (Dongdingwulong, DDWL; Tieguanyin, TGY; Dahongpao, DHP) were investigated in this study. Gas chromatography-olfactometry (GC-O) with the method of aroma intensity (AI) was employed to investigate the aroma-active compounds in tea infusions. The results presented forty-three, forty-five, and forty-eight aroma-active compounds in the TGY, DHP, and DDWL infusions, including six, seven, and five sulfur compounds, respectively. In addition, the concentration of volatile compounds in the tea infusions was further quantitated by solid phase microextraction-gas chromatography (SPME)-GC-MS and SPME-GC-flame photometric detection (FPD). Totally, seventy-six and thirteen volatile and sulfur compounds were detected in three types of tea infusions, respectively. Quantitative results showed that forty-seven aroma compounds were at concentrations higher than their corresponding odor thresholds. On the basis of the odor activity values (OAVs), 2-methylpropanal (OAV: 230-455), 3-methylbutanal (1-353), 2-methylbutanal (34-68), nerolidol (108-184), (E)-2-heptenal (148-294), hexanal (134-230), octanal (28-131), β-damascenone (29-59), indole (96-138), 6-methyl-5-hepten-2-one (34-67), (R)-(-)-linalool (63-87), and dimethyl sulfide (7-1320) presented relatively higher OAVs than those of other compounds, indicating the importance of these compounds in the overall aroma of tea infusions.

Metal-organic frameworks (MOFs), which are typically embedded in polymer matrices as composites, are emerging as a new class of carriers for sustained drug delivery. Most of the MOFs and the polymers used so far in these composites, however, are not pharmaceutically acceptable. In the investigation reported herein, composites of γ-cyclodextrin (γ-CD)-based MOFs (CD-MOFs) and polyacrylic acid (PAA) were prepared by a solid in oil-in-oil (s/o/o) emulsifying solvent evaporation method. A modified hydrothermal protocol has been established which produces efficiently at 50 °C in 6 h micron (5-10 μm) and nanometer (500-700 nm) diameter CD-MOF particles of uniform size with smooth surfaces and powder X-ray diffraction patterns that are identical with those reported in the literature. Ibuprofen (IBU) and Lansoprazole (LPZ), both insoluble in water and lacking in stability, were entrapped with high drug loading in nanometer-sized CD-MOFs by co-crystallisation (that is more effective than impregnation) without causing MOF crystal degradation during the loading process. On account of the good dispersion of drug-loaded CD-MOF nanocrystals inside polyacrylic acid (PAA) matrices and the homogeneous distribution of the drug molecules within these crystals, the composite microspheres exhibit not only spherical shapes and sustained drug release over a prolonged period of time, but they also demonstrate reduced cell toxicity. The cumulative release rate for IBU (and LPZ) follows the trend: IBU-γ-CD complex microspheres (ca. 80% in 2 h) > IBU microspheres > IBU-CD-MOF/PAA composite microspheres (ca. 50% in 24 h). Importantly, no burst release of IBU (and LPZ) was observed from the CD-MOF/PAA composite microspheres, suggesting an even distribution of the drug as well as strong drug carrier interactions inside the CD-MOF. In summary, these composite microspheres, composed of CD-MOF nanocrystals embedded in a biocompatible polymer (PAA) matrix, constitute an efficient and pharmaceutically acceptable MOF-based carrier for sustained drug release.

As the most basic protection for workers, safety helmets have great significance to workers' lives. However, due to a lack of safety awareness, safety helmets are often not worn. With the continuous development of object detection technology, the YOLO series of algorithms with very high precision and speed has been used in various scene detection tasks. To establish a digital safety helmet monitoring system, we propose a safety helmet detection method based on YOLOv5 and annotate the 6045 collected data sets. Finally, we used the YOLOv5 model with different parameters for training and testing. The four models are compared and analyzed. Experimental results show that the average detection speed of YOLOv5s reaches 110 FPS. Fully meet the requirements of real-time detection. Using the trainable target detector's pre-training weight, the mAP of YOLOv5x reaches 94.7%, proving the effectiveness of helmet detection based YOLOv5.

The noninvasive nature of photodynamic therapy (PDT) enables the preservation of organ function in cancer patients. However, PDT is impeded by hypoxia in the tumor microenvironment (TME) caused by high intracellular oxygen (O 2 ) consumption and distorted tumor blood vessels. Therefore, increasing oxygen generation in the TME would be a promising methodology for enhancing PDT. Herein, we proposed a concept of ferroptosis-promoted PDT based on the biochemical characteristics of cellular ferroptosis, which improved the PDT efficacy significantly by producing reactive oxygen species (ROS) and supplying O 2 sustainably through the Fenton reaction. In contrast to traditional strategies that increase O 2 based on decomposition of limited concentration of hydrogen peroxide (H 2 O 2 ), our methodology could maintain the concentration of H 2 O 2 and O 2 through the Fenton reaction. Methods: For its association with sensitivity to ferroptosis, solute carrier family 7 member 11 (SLC7A11) expression was characterized by bioinformatics analysis and immunohistochemistry of oral tongue squamous cell carcinoma (OTSCC) specimens. Afterwards, the photosensitizer chlorin e6 (Ce6) and the ferroptosis inducer erastin were self-assembled into a novel supramolecular Ce6-erastin nanodrug through hydrogen bonding and - stacking. Then, the obtained Ce6-erastin was extensively characterized and its anti-tumor efficacy towards OTSCC was evaluated both in vitro and in vivo. Results: SLC7A11 expression is found to be upregulated in OTSCC, which is a potential target for ferroptosis-mediated OTSCC treatment. Ce6-erastin nanoparticles exhibited low cytotoxicity to normal tissues. More significantly, The over-accumulated intracellular ROS, increased O 2 concentration and inhibited SLC7A11 expression lead to enhanced toxicity to CAL-27 cells and satisfactory antitumor effects to xenograft tumour mouse model upon irradiation. Conclusion: Our ferroptosis promoted PDT approach markedly enhances anticancer actions by relieving hypoxia and promoting ROS production, thereby our work provides a new approach for overcoming hypoxia-associated resistance of PDT in cancer treatment.

Abstract The electroreduction of carbon dioxide (CO 2 RR) to CH 4 stands as one of the promising paths for resourceful CO 2 utilization in meeting the imminent “carbon‐neutral” goal of the near future. Yet, limited success has been witnessed in the development of high‐efficiency catalysts imparting satisfactory methane selectivity at a commercially viable current density. Herein, a unique category of CO 2 RR catalysts is fabricated with the yolk–shell nanocell structure, comprising an Ag core and a Cu 2 O shell that resembles the tandem nanoreactor. By fixing the Ag core and tuning the Cu 2 O envelope size, the CO flux arriving at the oxide‐derived Cu shell can be regulated, which further modulates the *CO coverage and *H adsorption at the Cu surface, consequently steering the CO 2 RR pathway. Density functional theory simulations show that lower CO coverage favors methane formation via stabilizing the intermediate *CHO. As a result, the best catalyst in the flow cell shows a high CH 4 Faraday efficiency of 74 ± 2% and partial current density of 178 ± 5 mA cm − 2 at −1.2 V RHE , ranking above the state‐of‐the‐art catalysts reported today for methane production. These findings mark the significance of precision synthesis in tailoring the catalyst geometry for achieving desired CO 2 RR performance.

Recent developments of strategies on the construction of cyclobutanes and their application in complex natural product synthesis are discussed.

Abstract Green innovation is a key way for firms to establish competitive advantage and contribute to sustainable development, but it often suffers from financing constraints. In this regard, environmental, social, and governance (ESG) practices allow firms to have a wider investor base, face lower risk, and generate positive market reactions, ultimately leading to a lower cost of capital, which may potentially alleviate financing constraints and provide strong motivation for green innovation. Combining stakeholder theory with the resource‐based view (RBV), this study investigated how ESG substantially affects corporate green innovation. Based on a zero‐inflated Poisson regression analysis of 1577 listed Chinese manufacturing firms, we found that better ESG could significantly induce better corporate green innovation, and financing constraints acted as a mediator in the relationship between ESG and green innovation. Our findings contribute to a more detailed understanding of the mechanisms by which corporate pro‐social decision‐makings initiate and boost green innovation.

This paper briefly introduces the preparation and application of flavour and essential oils microcapsules based on complex coacervation technology. The conventional encapsulating agents of oppositely charged proteins and polysaccharides that are used for microencapsulation of flavours and essential oils are reviewed along with the recent advances in complex coacervation methods. Proteins extracted from animal-derived products (gelatin, whey proteins, silk fibroin) and from vegetables (soy proteins, pea proteins), and polysaccharides such as gum Arabic, pectin, chitosan, agar, alginate, carrageenan and sodium carboxymethyl cellulose are described in depth. In recent decades, flavour and essential oils microcapsules have found numerous potential practical applications in food, textiles, agriculturals and pharmaceuticals. In this paper, the different coating materials and their application are discussed in detail. Consequently, the information obtained allows criteria to be established for selecting a method for the preparation of microcapsules according to their advantages, limitations and behaviours as carriers of flavours and essential oils.