The simultaneous presence of two active metal centres in diatomic catalysts (DACs) leads to the occurrence of specific interactions between active sites. Such interactions, referred to as long‐range ...interactions (LRIs), play an important role in determining the rate and selectivity of a reaction. The optimal combination of metal centres must be determined to achieve the targeted efficiency. To date, various types of DACs have been synthesised and applied in electrochemistry. However, LRIs have not been systematically summarised. Herein, the regulation, mechanism, and electrocatalytic applications of LRIs are comprehensively summarised and discussed. In addition to the basic information above, the challenges, opportunities, and future development of LRIs in DACs are proposed in order to present an overall view and reference for future research.
Diatomic catalysts have attracted much attention, especially in electrochemistry. However, there have been no comprehensive reviews on long‐range interactions (LRIs) between metallic centres. This Minireview introduces the key aspects of LRIs and highlights opportunities for regulating electrocatalytic mechanisms, thus presenting guidelines for the targeted usage of LRIs.
Covalent organic frameworks (COFs), connecting different organic units into one system through covalent bonds, are crystalline organic porous materials with 2D or 3D networks. Compared with ...conventional porous materials such as inorganic zeolite, active carbon, and metal‐organic frameworks, COFs are a new type of porous materials with well‐designed pore structure, high surface area, outstanding stability, and easy functionalization at the molecular level, which have attracted extensive attention in various fields, such as energy storage, gas separation, sensing, photoluminescence, proton conduction, magnetic properties, drug delivery, and heterogeneous catalysis. Herein, the recent advances in metal‐free COFs as a versatile platform for heterogeneous catalysis in a wide range of chemical reactions are presented and the synthetic strategy and promising catalytic applications of COF‐based catalysts (including photocatalysis) are summarized. According to the types of catalytic reactions, this review is divided into the following five parts for discussion: achiral organic catalysis, chiral organic conversion, photocatalytic organic reactions, photocatalytic energy conversion (including water splitting and the reduction of carbon dioxide), and photocatalytic pollutant degradation. Furthermore, the remaining challenges and prospects of COFs as heterogeneous catalysts are also presented.
Covalent organic frameworks (COFs) as a new type of organic porous materials have aroused great interest in the field of heterogeneous catalysis. Herein, the applications of metal‐free COFs in organic catalysis, photocatalysis, energy conversion, and pollutant degradation are systematically summarized. In addition, the main challenges in this area and the potential prospects for future work are also discussed.
It is still of great difficulty to develop the non‐platinum catalyst with high catalytic efficiency towards hydrogen evolution reaction via the strategies till now. Therefore, it is necessary to ...develop the new methods of catalyst designing. Here, we put forward the catalyst designed by the electronic metal–support interaction (EMSI), which is demonstrated to be a reliable strategy to find out the high‐efficiency catalyst. We carried out the density functional theory calculation first to design the proper EMSI of the catalyst. We applied the model of M1‐M2‐X (X=C, N, O) during the calculation. Among the catalysts we chose, the EMSI of Rh1TiC, with the active sites of Rh1‐Ti2C2, is found to be the most proper one for HER. The electrochemical experiment further demonstrated the feasibility of the EMSI strategy. The single atomic site catalyst of Rh1‐TiC exhibits higher catalytic efficiency than that of state‐of‐art Pt/C. It achieves a small overpotential of 22 mV and 86 mV at the at the current density of 10 mA cm−2 and 100 mA cm−2 in acid media, with a Tafel slope of 25 mV dec−1 and a mass activity of 54403.9 mA cm−2 mgRh−1 (vs. 192.2 mA cm−2 mgPt−1 of Pt/C). Besides, it also shows appealing advantage in energy saving compared with Pt/C (≈20 % electricity consuming decrease at 2 kA m−2) Therefore, we believe that the strategy of regulating EMSI can act as a possible way for achieving the high catalytic efficiency on the next step of SACs.
The electronic metal–support interaction (EMSI) is closely related to the electronic structure of active sites, which determines the catalytic activity. We put forward a method of designing the EMSI of single‐atomic site catalysts (SACs) to achieve high efficiency. The SACs achieve a lower overpotential and higher mass activity than any other SACs towards hydrogen evolution reaction, demonstrating the benefits of this method.
A stimuli‐responsive lanthanide‐based smart nanocomposite has been fabricated by supramolecular assembly and applied as an active material in multidimensional memory materials. Conjugation of the ...lanthanide complexes with carbon dots provides a stimuli response that is based on the modulation of the energy level of the ligand and affords microsecond‐to‐nanosecond fluorescence lifetimes, giving rise to intriguing memory performance in the spatial and temporal dimension. The present study points to a new direction for the future development of multidimensional memory materials based on inorganic–organic hybrid nanosystems.
Hidden talents: A stimuli‐responsive lanthanide nanocomposite was fabricated by functionalization of carbon dots with lanthanide complexes and applied in a multidimensional memory device. The fluorescence lifetime and color can be changed by modulating the energy levels of the lanthanide ligand.
Although ether‐based electrolytes have been extensively applied in anode evaluation of batteries, anodic instability arising from solvent oxidability is always a tremendous obstacle to matching with ...high‐voltage cathodes. Herein, by rational design for solvation configuration, the fully coordinated ether‐based electrolyte with strong resistance against oxidation is reported, which remains anodically stable with high‐voltage Na3V2(PO4)2O2F (NVPF) cathode under 4.5 V (versus Na+/Na) protected by an effective interphase. The assembled graphite//NVPF full cells display superior rate performance and unprecedented cycling stability. Beyond that, the constructed full cells coupling the high‐voltage NVPF cathode with hard carbon anode exhibit outstanding electrochemical performances in terms of high average output voltage up to 3.72 V, long‐term cycle life (such as 95 % capacity retention after 700 cycles) and high energy density (247 Wh kg−1). In short, the optimized ether‐based electrolyte enriches systematic options, the ability to maintain oxidative stability and compatibility with various anodes, exhibiting attractive prospects for application.
By rational design of the solvation configuration, a cation–solvent fully coordinated ether‐based electrolyte with strong oxidation resistance up to 4.5 V (versus Na+/Na) was developed and applied in graphite//NVPF and LHC//NVPF full cells which showed superior rate performance and unprecedented cycling stability.
The exploitation of highly efficient carbon dioxide reduction (CO2RR) electrocatalyst for methane (CH4) electrosynthesis has attracted great attention for the intermittent renewable electricity ...storage but remains challenging. Here, N‐heterocyclic carbene (NHC)‐ligated copper single atom site (Cu SAS) embedded in metal–organic framework is reported (2Bn‐Cu@UiO‐67), which can achieve an outstanding Faradaic efficiency (FE) of 81 % for the CO2 reduction to CH4 at −1.5 V vs. RHE with a current density of 420 mA cm−2. The CH4 FE of our catalyst remains above 70 % within a wide potential range and achieves an unprecedented turnover frequency (TOF) of 16.3 s−1. The σ donation of NHC enriches the surface electron density of Cu SAS and promotes the preferential adsorption of CHO* intermediates. The porosity of the catalyst facilitates the diffusion of CO2 to 2Bn‐Cu, significantly increasing the availability of each catalytic center.
A catalyst with N‐heterocyclic carbene‐ligated Cu SAS as the active site, accompanied by many micro‐nano reactors, synergistically promotes the electrochemical synthesis of methane.
The features of well-conjugated and planar aromatic structures make π-conjugated luminescent materials suffer from aggregation caused quenching (ACQ) effect when used in solid or aggregated states, ...which greatly impedes their applications in optoelectronic devices and biological applications. Herein, we reduce the ACQ effect by demonstrating a facile and low cost method to co-assemble polycyclic aromatic hydrocarbon (PAH) chromophores and octafluoronaphthalene together. Significantly, the solid photoluminescence quantum yield (PLQYs) for the as-resulted four micro/nanococrystals are enhanced by 254%, 235%, 474 and 582%, respectively. Protection from hydrophilic polymer chains (P123 (PEO
-PPO
-PEO
)) endows the cocrystals with superb dispersibility in water. More importantly, profiting from the above-mentioned highly improved properties, nano-cocrystals present good biocompatibility and considerable cell imaging performance. This research provides a simple method to enhance the emission, biocompatibility and cellular permeability of common chromophores, which may open more avenues for the applications of originally non- or poor fluorescent PAHs.
Chlorine evolution reaction has been applied in the production since a century ago. After times of evolution, it has been widely realized by the electrocatalytic process on anode nowadays. However, ...the anode applied in production contains a large amount of precious metal, increasing the cost. It is thus an opportunity to apply sub‐nano catalysts in this field. By regulating the tip effect (TE) of the catalyst, it was discovered that the oxidized sub‐nano iridium clusters supported by titanium carbide exhibit much higher efficiency than the single‐atom one, which demonstrates the significance of modifying the electronic interaction. Moreover, it exhibits a ≈20 % decrease of the electricity, ≈98 % selectivity towards chlorine evolution reaction, and high durability of over 350 h. Therefore, this cluster catalyst performs great potential in applying in the practical production and the comprehension of the tip effect on different types of catalysts is also pushed to a higher level.
The tip effect (TE) has not been mentioned enough in catalysts designing, having a large space to explore. Based on the model of oxidized sub‐nano clusters, the TE was regulated and found to be efficient in designing catalysts, making TiC perform a high activity during the chlor‐alkali industry. This cluster system exhibits great potential in applying in the practical production and the comprehension of the TE is also pushed to a higher level.
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