Diverse atomic structure configurations of metal-doped transition metal dichalcogenides for enhancing hydrogen evolution

Doping foreign metal atoms into the substrate of transition metal dichalcogenides(TMDs)enables the formation of diverse atomic structure configurations,including isolated atoms,chains,and clusters.Therefore,it is very important to reasonably control the atomic structure and determine the structure-activity relationship between the atomic configurations and the hydrogen evolution reaction(HER)performance.Although numerous studies have indicated that doping can yield diverse atomic structure configurations,there remains an incomplete understanding of the relationship between atomic configurations within the lattice of TMDs and their performance.Here,diverse atomic structure configurations of adsorptive doping,substitutional doping,and TMDs alloys are summarized.The structure-activity relationship between different atomic configurations and HER performance can be determined by micro-nanostructure devices and density functional theory(DFT)calculations.These diverse atomic structure configurations are of great significance for activating the inert basal plane of TMDs and improving the catalytic activity of HER.Finally,we have summarized the current challenges and future opportunities,offering new perspectives for the design of highly active and stable metal-doped TMDs catalysts.

The strategies to improve TMDs represented by MoS_(2)electrocatalytic oxygen evolution reaction

The hydrogen evolution reaction(HER)and the oxygen evolution reaction(OER)are the two half reactions that make up the over water splitting reaction.Increasing oxygen evolution reaction rate wound immensely raise the efficiency of over water splitting reaction because it is the rate limiting reaction in water splitting reaction.The key to improve OER performance is the development and utilization of advanced catalysts.As one of the most potential catalysts for HER,it has gradually attracted the attention of researchers in the aspect of catalytic OER.It is very necessary to review the research progress of Transition metal dichalcogenides(TMDs)in catalytic OER to promote the research process in the field.In this review,we comprehensively and systematically summarized the strategies to improve TMDs electrocatalytic OER.First of all,structural regulation of TMDs-based electrocatalyst was summarized in detail,mainly including size engineering,defect engineering,doping engineering,phase engineering and heterojunction engineering.Once more,magnetic field regulation as a representative of external field regulation to improve TMDs electrocatalytic OER performance was discussed in depth.Last but not least,the strategies to improve TMDs electrocatalytic OER is prospected and some views on the development of this field are also put forward,which are expected to enhance the catalytic efficiency of TMDs for OER.

Circularly polarized luminescence from organic micro-/nano-structures

Circularly polarized light exhibits promising applications in future displays and photonic technologies.Circularly polarized luminescence(CPL)from chiral luminophores is an ideal approach to directly generating circularly polarized light,in which the energy loss induced by the circularly polarized filters can be reduced.Among various chiral luminophores,organic micro-/nano-structures have attracted increasing attention owing to the high quantum efficiency and luminescence dissymmetry factor.Herein,the recent progress of CPL from organic micro-/nano-structures is summarized.Firstly,the design principles of CPL-active organic micro-/nano-structures are expounded from the construction of micro-/nano-structure and the introduction of chirality.Based on these design principles,several typical organic micro-/nano-structures with CPL activity are introduced in detail,including self-assembly of small molecules,self-assembly ofπ-conjugated polymers,and self-assembly on micro-/nanoscale architectures.Subsequently,we discuss the external stimuli that can regulate CPL performance,including solvents,pH value,metal ions,mechanical force,and temperature.We also summarize the applications of CPL-active materials in organic light-emitting diodes,optical information processing,and chemical and biological sensing.Finally,the current challenges and prospects in this emerging field are presented.It is expected that this review will provide a guide for the design of excellent CPL-active materials.

Dislocation-strained MoS_(2)nanosheets for high-efficiency hydrogen evolution reaction

Defect engineering is one of the effective strategies to optimize the physical and chemical properties of molybdenum disulfide(MoS_(2))to improve catalytic hydrogen evolution reaction(HER)performance.Dislocations,as a typical defect structure,are worthy of further investigation due to the versatility and sophistication of structures and the influence of local strain effects on the catalytic performance.Herein,this study adopted a low-temperature hydrothermal synthesis strategy to introduce numerous dislocation-strained structures into the in-plane and out-of-plane of MoS_(2)nanosheets.Superior HER catalytic activity of 5.85 mmol·g^(−1)·h^(−1)under visible light was achieved based on the high-density dislocations and the corresponding strain field.This work paves a new pathway for improving the catalytic activity of MoS_(2)via a dislocation-strained synergistic modulation strategy.

Mitochondria-localized iridium(Ⅲ) complexes with anthraquinone groups as effective photosensitizers for photodynamic therapy under hypoxia

Photodynamic therapy（PDT） is a potential way for the tumor treatment. However, it notably suffers the limitation of hypoxia in solid tumors. Thus, it is significant to develop effective photosensitizers which can exhibit excellent therapeutic performance under both normoxia and hypoxia. Herein, we reported four ionic iridium（III） complexes（Ir1–Ir4） with anthraquinone groups which can regulate their excited state energy levels effectively. Among them, the energy gap of Ir1 was between 1.63 and 2.21 eV, which can match well with that of O2, and the HOMO energy of Ir1 is less than-5.51 eV. Compared with Ir2–Ir4, the luminescent quantum efficiency of Ir1 was the highest. Particularly, Ir1 can specifically target the mitochondria of the tumor cells. Meanwhile, Ir1 showed high singlet oxygen quantum yields（ΦΔ） in both solutions and living cells with low cytotoxicity.The results of PDT experiments revealed that Ir1, as a photosensitizer, exhibited excellent therapeutic effect not only in normoxia but also in hypoxia condition. We believe that this work is meaningful for developing excellent PDT agents based on cyclometalated Ir（III） complexes via rational ligand modification.

Organic photoresponsive materials for information storage:a review

Organic photoresponsive materials can undergo various reversible variations in certain physical and chemical properties,such as optical properties,electrochemical properties,conformation,and conductivity,upon photoirradiation.They have been widely applied in various optoelectronic fields,especially in information storage.We summarize research progress on organic photoresponsive materials for information storage.First,the design strategies and photoswitching mechanisms for various kinds of organic photoresponsive materials,including small organic molecules,metal complexes,polymers,supramolecules,and cholesteric liquid crystals,are systematically summarized.These materials exhibit reversible changes of absorption and/or emission properties in response to different wavelengths of light.Subsequently,the applications of these organic materials in information storage,such as data(re)writing and erasing,encryption and decryption,and anticounterfeiting,are introduced in detail.Finally,the current challenges and future directions in this rapidly growing research field are discussed.The review will provide important guidance on the future works about the design of excellent organic photoresponsive materials for optoelectronic applications.

Soluble triarylamine functionalized symmetric viologen for all-solid-state electrochromic supercapacitors

Electrochromic supercapacitors have drawn enormous attention due to their ability to monitor the charge and discharge processes through color changes of electroactive materials.However,there are few work on small organic molecules as active materials for all-solid-state electrochromic supercapacitors.Herein,we reported two novel multifunctional symmetric viologens(TPA-bpy and CZ-bpy),which showed different solvatochromic,electrochromic,electroluminochromic and energy storage behaviors despite their similar chemical structures.The different performances between these two viologens were attributed to the difference in the intramolecular charge transfer capability and the solubility in organic solvents.Devices containing TPA-bpy displayed faster response time and higher coloration efficiency due to the introduction of packing-disruptive and three-dimensional triarylamine groups.Moreover,devices containing TPA-bpy also showed energy storage characteristics with an obvious color change from purple to yellow.It showed a wide voltage window(2.0 V),long discharge time(230.3 s at 0.01 mA cm−2),and excellent cycling stability with 90%capacitance retention after 6,000 cycles.The work provides a new and convenient strategy towards the development of novel electrochromic capacitive materials.