Cyclodextrins (CDs), which are a class of cyclic oligosaccharides extracted from the enzymatic degradation of starch, are often utilized in molecular recognition and assembly constructs, primarily ...via host–guest interactions in water. In this review, recent progress in CD‐based supramolecular nanoassemblies that are sensitive to chemical, biological, and physical stimuli is updated and reviewed, and intriguing examples of the biological functions of these nanoassemblies are presented, including pH‐ and redox‐responsive drug and gene delivery, enzyme‐activated specific cargo release, photoswitchable morphological interconversion, microtubular aggregation, and cell–cell communication, as well as a geomagnetism‐controlled nanosystem for the suppression of tumor invasion and metastasis. Moreover, future perspectives and challenges in the fabrication of intelligent CD‐based biofunctional materials are also discussed at the end of this review, which is expected to promote the translational development of these nanomaterials in the biomedical field.
Recent progress in cyclodextrin‐based multistimuli‐responsive supramolecular assemblies is systematically reviewed, their biological functions are presented by selecting some representative examples, and future perspectives and challenges in this promising field are discussed.
The construction of controlled biomacromolecular assemblies has become a thriving area of supramolecular chemistry. In this context, cucurbiturils (CBs), a class of macrocyclic receptors having ...robust skeletons, hydrophobic cavities, and carbonyl‐laced portals, have been drawn into the limelight because of their advantageous molecular recognition characteristics with a variety of biomacromolecules, including peptides, nucleic acids, and proteins. In this minireview, we focus on the impressive advances in CB‐based biomacromolecular assemblies, such as in biosensors and assays, the regulation of biochemical reactions, and the treatment of serious diseases. CB‐promoted subcellular bioimaging has also been demonstrated in different organelles. The case studies presented herein demonstrate the numerous applications, from fundamental research to translational applications, of diverse CB‐based supra/biomacromolecular architectures.
This minireview highlights the recent progress in and emerging applications of cucurbituril‐based biomacromolecular assemblies with peptides, nucleic acids, and proteins. This rapidly developing area involves precise control over intermolecular communication at multidimensional levels and holds great promise for the creation of innovative biomaterials and therapeutic methods.
The aprotic lithium–oxygen (Li–O2) battery has excited huge interest due to it having the highest theoretical energy density among the different types of rechargeable battery. The facile achievement ...of a practical Li–O2 battery has been proven unrealistic, however. The most significant barrier to progress is the limited understanding of the reaction processes occurring in the battery, especially during the charging process on the positive electrode. Thus, understanding the charging mechanism is of crucial importance to enhance the Li–O2 battery performance and lifetime. Here, recent progress in understanding the electrochemistry and chemistry related to charging in Li–O2 batteries is reviewed along with the strategies to address the issues that exist in the charging process at the present stage. The properties of Li2O2 and the mechanisms of Li2O2 oxidation to O2 on charge are discussed comprehensively, as are the accompanied parasitic chemistries, which are considered as the underlying issues hindering the reversibility of Li–O2 batteries. Based on the detailed discussion of the charging mechanism, innovative strategies for addressing the issues for the charging process are discussed in detail. This review has profound implications for both a better understanding of charging chemistry and the development of reliable rechargeable Li–O2 batteries in the future.
Addressing the challenges facing lithium–oxygen (Li–O2) batteries during charging is of great significance for improving the performance of Li–O2 batteries. A fundamental discussion on the science underpinning the charging chemistry of the Li–O2 system and on promising strategies for improving these reactions is presented. The findings have deep implications for the future development of reliable rechargeable Li–O2 batteries.
Both the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are crucial to water splitting, but require alternative active sites. Now, a general π‐electron‐assisted strategy to ...anchor single‐atom sites (M=Ir, Pt, Ru, Pd, Fe, Ni) on a heterogeneous support is reported. The M atoms can simultaneously anchor on two distinct domains of the hybrid support, four‐fold N/C atoms (M@NC), and centers of Co octahedra (M@Co), which are expected to serve as bifunctional electrocatalysts towards the HER and the OER. The Ir catalyst exhibits the best water‐splitting performance, showing a low applied potential of 1.603 V to achieve 10 mA cm−2 in 1.0 m KOH solution with cycling over 5 h. DFT calculations indicate that the Ir@Co (Ir) sites can accelerate the OER, while the Ir@NC3 sites are responsible for the enhanced HER, clarifying the unprecedented performance of this bifunctional catalyst towards full water splitting.
HER and OER! The hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) are crucial to water splitting, but require alternative active sites. Now, a general π‐electron‐assisted strategy to anchor single‐atom sites (M=Ir, Pt, Ru, Pd, Fe, Ni) on a heterogeneous support is reported. The M atoms can simultaneously anchor on two distinct domains of the hybrid support, four‐fold N/C atoms, and centers of Co octahedra.
The electrochemical N2 fixation, which is far from practical application in aqueous solution under ambient conditions, is extremely challenging and requires a rational design of electrocatalytic ...centers. We observed that bismuth (Bi) might be a promising candidate for this task because of its weak binding with H adatoms, which increases the selectivity and production rate. Furthermore, we successfully synthesized defect‐rich Bi nanoplates as an efficient noble‐metal‐free N2 reduction electrocatalyst via a low‐temperature plasma bombardment approach. When exclusively using 1H NMR measurements with N2 gas as a quantitative testing method, the defect‐rich Bi(110) nanoplates achieved a 15NH3 production rate of 5.453 μg mgBi−1 h−1 and a Faradaic efficiency of 11.68 % at −0.6 V vs. RHE in aqueous solution at ambient conditions.
Beneficial defects: Defect‐rich bismuth nanoplates achieve a 15NH3 production rate of 5.453 μg mgBi−1 h−1 and a Faradaic efficiency of 11.68 % at −0.6 V vs. RHE in aqueous solutions at ambient conditions because of their poor binding with H adatoms, which increases the selectivity and production rate. Also, 1H NMR measurements with N2 gas ware used as a quantitative test method in aqueous electrolytes.
Prussian blue analogues (PBAs, A2TM(CN)6, A = Li, K, Na; T = Fe, Co, Ni, Mn, Cu, etc.; M = Fe, Mn, Co, etc.) are a large family of materials with an open framework structure. In recent years, they ...have been intensively investigated as active materials in the field of energy conversion and storage, such as for alkaline‐ion batteries (lithium‐ion, LIBs; sodium‐ion, NIB; and potassium‐ion, KIBs), and as electrochemical catalysts. Nevertheless, few review papers have focused on the intrinsic chemical and structural properties of Prussian blue (PB) and its analogues. In this Review, a comprehensive insight into the PBAs in terms of their structural and chemical properties, and the effects of these properties on their materials synthesis and corresponding performance is provided.
This Review provides a comprehensive overview of the latest research progress on Prussian blue analogues (PBAs), including the synthesis methods, structural and chemical properties of PBAs, various applications for these PBAs, and the effects of their structural and chemical properties on material synthesis and applications. Finally, some personal viewpoints on the challenges and outlook for PBAs application are included.
A global parameter estimation method for a permanent magnet synchronous machines (PMSM) drive system is proposed, where the electrical parameters, mechanical parameters, and voltage-source-inverter ...(VSI) nonlinearity are regarded as a whole and parameter estimation is formulated as a single parameter optimization model. A dynamic learning estimator is proposed for tracking the electrical parameters, mechanical parameters, and VSI of PMSM drive by using dynamic self-learning particle swarm optimization (DSLPSO). In DSLPSO, a novel movement modification equation with dynamic exemplar learning strategy is designed to ensure its diversity and achieve a reasonable tradeoff between the exploitation and exploration during the search process. Moreover, a nonlinear multiscale based interactive learning operator is introduced for accelerating the convergence speed of the <inline-formula><tex-math notation="LaTeX"> Pbest</tex-math></inline-formula> particles; meanwhile a dynamic opposition-based learning strategy is designed to facilitate the <inline-formula><tex-math notation="LaTeX">gBest</tex-math></inline-formula> particle to explore a potentially better region. The proposed algorithm is applied to parameter estimation for a PMSM drive system. The results show that the proposed method has better performance in tracking the variation of electrical parameters, and estimating the immeasurable mechanical parameters and the VSI disturbance voltage simultaneously.
As one of the most competitive candidates for large‐scale energy storage, zinc–air batteries (ZABs) have attracted great attention due to their high theoretical specific energy density, low toxicity, ...high abundance, and high safety. It is highly desirable but still remains a huge challenge, however, to achieve cheap and efficient electrocatalysts to promote their commercialization. Recently, Fe‐based single‐atom and dual‐atom catalysts (SACs and DACs, respectively) have emerged as powerful candidates for ZABs derived from their maximum utilization of atoms, excellent catalytic performance, and low price. In this review, some fundamental concepts in the field of ZABs are presented and the recent progress on the reported Fe‐based SACs and DACs is summarized, mainly focusing on the relationship between structure and performance at the atomic level, with the aim of providing helpful guidelines for future rational designs of efficient electrocatalysts with atomically dispersed active sites. Finally, the great advantages and future challenges in this field of ZABs are also discussed.
In this review, the authors provide a comprehensive survey on recent research in Fe‐based single‐atom/dual‐atom electrocatalysts applied as air electrodes of zinc–air batteries, and deeply discuss the relationship between active‐site coordination and battery performance, potentially offering guidelines for future related investigations.
The low-cost room-temperature sodium-sulfur battery system is arousing extensive interest owing to its promise for large-scale applications. Although significant efforts have been made, resolving low ...sulfur reaction activity and severe polysulfide dissolution remains challenging. Here, a sulfur host comprised of atomic cobalt-decorated hollow carbon nanospheres is synthesized to enhance sulfur reactivity and to electrocatalytically reduce polysulfide into the final product, sodium sulfide. The constructed sulfur cathode delivers an initial reversible capacity of 1081 mA h g
with 64.7% sulfur utilization rate; significantly, the cell retained a high reversible capacity of 508 mA h g
at 100 mA g
after 600 cycles. An excellent rate capability is achieved with an average capacity of 220.3 mA h g
at the high current density of 5 A g
. Moreover, the electrocatalytic effects of atomic cobalt are clearly evidenced by operando Raman spectroscopy, synchrotron X-ray diffraction, and density functional theory.
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