Structure–property–performance relationship of vanadium- and manganese-based metal–organic frameworks and their derivatives for energy storage and conversion applications

Abstract

The energy crises are currently the main challenges for human life. Promising solutions are expected from research on novel materials with a wide range of functional benefits. The new family...

Copper-Based Bio-MOF/GO with Lewis Basic Sites for CO2 Fixation into Cyclic Carbonates and C–C Bond-Forming Reactions

“…Metal–organic frameworks (MOFs) belong to a category of functional materials with considerable crystallinity and porosity. Their unique characteristics, such as significantly high surface area, functional tunability, great stability, open channels, adjustability, coherent structural porosity, high CO 2 adsorption capacity, and long-lasting porosity, have made these materials promising candidates in catalysis. − The chemical characteristics of MOFs are adequately manageable relative to other porous materials, including active carbon, zeolites, and mesoporous silica, which are mainly attributed to their various functional groups. − Although environments and coordination modes are nonuniformly distributed in many supported catalysts, which diminishes product selectivity, MOFs have regular catalytic sites, leading to product selectivity comparable to those of their homogeneous counterparts. − Several active metal sites within the same framework can be combined, or active species can be incorporated into the MOF linkers or within their pores to construct MOFs with large pore apertures and a high density of available metal sites. − These valuable characteristics have inspired the development of MOFs for various sophisticated catalytic applications, including CO 2 insertion into epoxide and Knoevenagel condensation reactions. , …”

Nano-Nest Type Porous NiCo2S4@polyindole Core–Shell Array: Efficient Energy Storage Supercapacitor Device

“…Fast consumption of fossil energy sources and consequent anticipated crises have been acknowledged globally, and serious efforts are being made to switch to alternate power sources by exploring new and efficient energy conversion and storage devices. − (Super-) capacitors have their practical applicability due to their high power density, fast charge–discharge, easy synthesis, high capacitance retention, high mechanical strength, and better ecological coexistence. − Nevertheless, the low energy density of supercapacitors always restricts their practical applications due to the small operational potential window. , To increase the energy density, asymmetric supercapacitors are fabricated with positive electrodes as high-specific capacitance material to increase the power density and negative electrodes (negatrodes) as carbonaceous material (usually activated carbon) to increase the energy density of the device. , In addition to these carbon materials, transition metal sulfides have emerged as promising positive electrode materials for supercapacitors − owing to the advantages of ultrahigh theoretical specific capacitance, excellent cyclic stability, and fast ion diffusion rate. Among them, NiS x and CoS x are the most reported metal sulfide supercapacitors; however, their specific capacitance is always higher than that of their corresponding metal oxides under the same experimental conditions, which is attributed to their high electrical conductivity. − The specific capacitance can further be improved if dual metal sulfides such as NiCo 2 S 4 (NCS) and CuCo 2 S 4 are used due to their strong redox reactions and high theoretical specific capacitance.…”

“…9,10 To increase the energy density, asymmetric supercapacitors are fabricated with positive electrodes as high-specific capacitance material to increase the power density and negative electrodes (negatrodes) as carbonaceous material (usually activated carbon) to increase the energy density of the device. 11,12 In addition to these carbon materials, transition metal sulfides have emerged as promising positive electrode materials for supercapacitors 13−16 owing to the advantages of ultrahigh theoretical specific capacitance, excellent cyclic stability, and fast ion diffusion rate. Among them, NiS x and CoS x are the most reported metal sulfide supercapacitors; however, their specific capacitance is always higher than that of their corresponding metal oxides under the same experimental conditions, which is attributed to their high electrical conductivity.…”