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With the excessive consumption of nonrenewable resources, the exploration of effective and durable materials is highly sought after in the field of sustainable energy conversion and storage system. In this aspect, metal‐organic frameworks (MOFs) are a new class of crystalline porous organic‐inorganic hybrid materials. MOFs have recently been gaining traction in energy‐related fields. Owing to the coordination flexibility and multiple accessible oxidation states of vanadium ions or clusters, vanadium‐MOFs (V‐MOFs) possess unique structural characteristics and satisfactory electrochemical properties. Furthermore, V‐MOFs‐derived materials also exhibit superior electrical conductivity and stability when used as electrocatalysts and electrode materials. This review summarizes the research progress of V‐MOFs (inclusive of pristine V‐MOFs, V/M‐MOFs, and POV‐based MOFs) and their derivatives (vanadium oxides, carbon‐coated vanadium oxide, vanadium phosphate, vanadate, and other vanadium doped nanomaterials) in electrochemical energy conversion (water splitting, oxygen reduction reaction) and energy storage (supercapacitor, rechargeable battery). Future possibilities and challenges for V‐MOFs and their derivatives in terms of design and synthesis are discussed. Lastly, their applications in energy‐related fields are also highlighted. [ABSTRACT FROM AUTHOR]

Sodium‐ion batteries (SIBs) have aroused great attention because of the low cost and environmental benignity of sodium resources. However, practical applications of SIBs are plagued by the sluggish kinetics of sodium ions with large size in the host structure, which results in poor rate performance and rapid capacity decline. Herein, a self‐templated approach was developed to synthesize MoS2/Cu2Se nanosheets with improved interfacial electron‐ and ion‐transfer kinetics. The MoS2/Cu2Se nanosheets provided superior sodium storage performance, delivering 139 mAh g−1 at a high current density of 100 A g−1 and 222 mAh g−1 after 14000 cycles (at 20 A g−1). The outstanding electrochemical performance was attributed to the synergetic engineering of interface and structure, which could enhance the electrochemical kinetics and gave excellent mechanical properties to deal with the volume expansion phenomenon. Combined with a high‐voltage cathode, the full battery demonstrated a high energy density of 152 Wh kg−1 at a power density of 420 W kg−1, which opens a new avenue for the development of high‐performance SIBs. [ABSTRACT FROM AUTHOR]

Ultrathin metal–organic framework (MOF) nanosheets (NSs) offer potential for many applications, but the synthetic strategies are largely limited to top‐down, low‐yield exfoliation methods. Herein, Ni–M–MOF (M=Fe, Al, Co, Mn, Zn, and Cd) NSs are reported with a thickness of only several atomic layers, prepared by a large‐scale, bottom‐up solvothermal method. The solvent mixture of N,N‐dimethylacetamide and water plays key role in controlling the formation of these two‐dimensional MOF NSs. The MOF NSs can be directly used as efficient electrocatalysts for the oxygen evolution reaction, in which the Ni–Fe–MOF NSs deliver a current density of 10 mA cm−2 at a low overpotential of 221 mV with a small Tafel slope of 56.0 mV dec−1, and exhibit excellent stability for at least 20 h without obvious activity decay. Density functional theory calculations on the energy barriers for OER occurring at different metal sites confirm that Fe is the active site for OER at Ni–Fe–MOF NSs. [ABSTRACT FROM AUTHOR]

Abstract: Metal–organic frameworks (MOFs) are a class of promising materials for diverse heterogeneous catalysis, but they are usually not directly employed for oxygen evolution electrocatalysis. Most reports focus on using MOFs as templates to in situ create efficient electrocatalysts through annealing. Herein, we prepared a series of Fe/Ni‐based trimetallic MOFs (Fe/Ni/Co(Mn)‐MIL‐53 accordingly to the Material of Institute Lavoisier) by solvothermal synthesis, which can be directly adopted as highly efficient electrocatalysts. The Fe/Ni/Co(Mn)‐MIL‐53 shows a volcano‐type oxygen evolution reaction (OER) activity as a function of compositions. The optimized Fe/Ni2.4/Co0.4‐MIL‐53 can reach a current density of 20 mA cm−2 at low overpotential of 236 mV with a small Tafel slope of 52.2 mV dec−1. In addition, the OER performance of these MOFs can be further enhanced by directly being grown on nickel foam (NF). [ABSTRACT FROM AUTHOR]

An efficient method for synthesis of 1,3-diynes through the CuI/1,10-phenanthroline-catalyzed oxidative decarboxylative homocoupling of aryl pioprolic acids in aqueous DMF has been developed. The catalytic system was suitable for a variety of arylpropiolic acids, and the corresponding 1,3-diynes could be prepared in high yields. The catalytic system was recovered from the organic products by filtration and its aqueous DMF filtrate retained good activity even after at least four cycles of use. [ABSTRACT FROM AUTHOR]

The development of highly active, stable, low‐cost, and earth‐abundant electrocatalysts for both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) remains a great challenge. Herein, the cobalt (Co)‐modified MoS2 hybrid catalysts grown on nickel foam (NF) are successfully synthesized by a facile solvothermal method. The optimized catalyst (denoted as Co‐Mo‐S‐2/NF) shows excellent HER activity with low overpotentials of 77 and 96 mV at a current density of 10 mA cm−2, as well as excellent stability with negligible loss of the cathodic current after 3000 cycles in 1.0 M KOH and 1.0 M phosphate‐buffered saline (pH = 7), respectively. Significantly, when used as OER catalyst, the Co‐Mo‐S‐2/NF hybrid also displays outstanding OER activity with a low overpotential of 294 mV at a current density of 10 mA cm−2 and good long‐term stability for 120 h at 10 mA cm−2 without observable fading under alkaline condition. The excellent electrocatalytic activity of the generated catalyst is mainly due to abundant active site, large active area, improved conductivity, and synergistic effect within MoS2, Co9S8, and CoMoS3.13. This work provides a unique strategy to design the high‐performance and stable electrocatalysts for HER and OER. [ABSTRACT FROM AUTHOR]

The article presents chemical equations related to the article "Efficient and Reusable CuI/1,10-Phenanthroline-Catalyzed Oxidative Decarboxylative Homocoupling of Arylpropiolic Acids in Aqueous DMF" by D.-X. Liu and others, published in the "European Journal of Organic Chemistry" in 2014.

The article highlights the chemical equations involved in the synthesis of 1,4-diarylsubstituted 1,3-diynes.