Zeolitic imidazolate frameworks (ZIFs) are a subclass of metal-organic frameworks (MOFs). In this work, the nickel titanate (NiTiO3) nanoparticles and ZIF based nickel titanate (ZIF@NiTiO3) were ...prepared by sol-gel method and were characterized by powder X-Ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), Scanning Electron Microscopy (SEM) and BET(Brunauer-Emmett-Teller) methods. The NiTiO3 had rhombohedral crystal structure and crystallite size of 40−50 nm. FTIR confirmed of composite and metal-oxide NiO and TiO bands. BET analysis showed ZIF@NiTiO3 nanocomposite had higher surface area (345 m2 g−1) than NiTiO3 (31 m2 g−1). The adsorption studies of Pb(II) by NiTiO3 and ZIF@NiTiO3 nanocomposite were carried out by batch method. The effects of varying parameters like contact time; pH and mass of sorbent on Pb(II) were investigated. The ZIF@NiTiO3 was found to follow by pseudo second order kinetic model better than the pseudo-first order (k2 = 1.3 × 10 -2), since the adsorption isotherm experimental data was fitted better by Langmuir model than Freundlich and Temkin models. The maximum adsorption capacity of Pb(II) for NiTiO3 and ZIF@NiTiO3 was observed 72 and 155 mg g−1, respectively at pH 5. ZIF@NiTiO3 acts as sufficient reusable sorbent for Pb(II).
Heterostructure nanorods are constructed by interconnected NiSe2 and CoSe2 nanoparticles based on cone-like ZIF-L. Due to the design of the granular nanorod arrays structure, the hierarchical ...flexible nanoarrays reflect rich redox active sites, outstanding capacitance performance and excellent structural stability.
Display omitted
•The one-dimensional (Ni, Co)Se2 nanoarrays based on cone-like ZIF-L were successfully designed.•A single nanorod is composed of interconnected NiSe2 and CoSe2 nanoparticles.•Due to the design of granular heterostructure, the hierarchical flexible nanoarrays reflect rich redox active sites.•The hybrid supercapacitor of CF@(Ni,Co)Se2//AC achieves an excellent electrochemical property.
The construction of heterostructure could enhance the electron transfer efficiency and increase the number of active sites, which can further develop high-performance electrode materials of supercapacitors. Herein, (Ni, Co)Se2 nanorod arrays were prepared based on the NiCo-LDH derived from a conical ZIF-L. Significantly, the single nanorod is composed of interconnected NiSe2 and CoSe2 nanoparticles, the heterostructure can expose higher conductivity, more sufficient redox reaction active sites and larger specific surface area. The as-obtained CF@(Ni, Co)Se2 achieved a high specific capacity of 188.8 mAh g−1 at the current density of 1.0 A g−1 and an outstanding cycling stability with a high capacity retention of 90% after 8000 cycles. Finally, an hybrid supercapacitor device composed of activated carbon (AC) as negative electrode and CF@(Ni, Co)Se2 as positive electrode was designed, which revealed an ideal voltage window of 0–1.6 V and exhibited a great energy density of 36.02 Wh kg−1 at the power density of 800 W kg−1, such surpassing energy storage characteristics evidently testify that (Ni, Co)Se2 nanorod arrays can be as the potential electrode material to promote the development of high-performance supercapacitors.
•Material concentrations of UiO-66, MIL-88B and ZIF-8 have similar impact on cytotoxicity with respect to gene delivery.•ZIF-8 possessed the highest gene loading (nearly 90%) capacity; UiO-66 and ...MIL-88B did not demonstrate gene loading under physiologically favourable conditions.•Gene loading with ZIF-8 fully retained gene functional activity.•ZIF-8 is a biologically neutral gene delivery material with minimal changes to basal cellular metabolism.•Lack of apparent immunotoxicity of gene@ZIF-8 – no overexpression of cytokines; suppression of inflammation promoting cytokine IL8, along with normal expression of anti-inflammatory cytokine IL10.
Metal-organic frameworks (MOFs) are an emerging group of nanomaterials for successful biomedical applications in gene therapy. The most commonly biocompatible MOFs are zinc-based ZIFs, zirconium-based UiOs, and iron-based MILs. However, despite increasing applications, a comparative study to underscore the critical factors for determining effective gene delivery by such MOFs is lacking. Herein, we evaluate the potential of UiO-66 and MIL-88B and ZIF-8 for gene therapeutics delivery; revealing the comparative importance of ZIF-8. Cytotoxicity assays proved insufficient for selecting the ideal gene delivery MOF vehicle. Synthesis conditions such as ability of the MOF scaffold to envelop the gene during in-situ synthesis, post-treatment such as washing, and gene loading efficiency proved to be the critical factors in determining the favourable MOF from the material selection perspective. Rapid in-situ synthesis under physiological conditions, successful gene loading, and low concentration requirements favour ZIF MOFs as gene delivery vehicles. Impact on cellular physiology, metabolism, and architecture revealed neutrality of the delivery system; and relative effects on pro-inflammatory and anti-inflammatory cytokines suggest immunomodulatory impact.
Designing a highly active electrocatalyst with optimal stability at low cost is must and non‐negotiable if large‐scale implementations of fuel cells are to be fully realized. Zeolitic‐imidazolate ...frameworks (ZIFs) offer rich platforms to design multifunctional materials due to their flexibility and ultrahigh surface area. Herein, an advanced Co–Nx/C nanorod array derived from 3D ZIF nanocrystals with superior electrocatalytic activity and stability toward oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) compared to commercial Pt/C and IrO2, respectively, is synthesized. Remarkably, as a bifunctional catalyst (Ej = 10 (OER) − E1/2 (ORR) ≈ 0.65 V), it further displays high performance of Zn–air batteries with high cycling stability even at a high current density. Such supercatalytic properties are largely attributed to the synergistic effect of the chemical composition, high surface area, and abundant active sites of the nanorods. The activity origin is clarified through post oxygen reduction X‐ray photoelectron spectroscopy analysis and density functional theory studies. Undoubtedly, this approach opens a new avenue to strategically design highly active and performance‐oriented electrocatalytic materials for wider electrochemical energy applications.
A highly active bifunctional electrocatalyst is designed via a structural transformation of 3D ZIF nanocrystals into an array of 1D metal/N functionalized carbon nanorod frameworks. The obtained catalyst exhibits superior bifunctional activity and stability toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), leading to high Zn‐air battery performances compared to the state‐of‐the‐art counterparts.
In the global pursuit of sustainable energy, solar-powered resources have received significant attention due to their potential to provide clean and renewable energy. Among these, PEC water splitting ...stands out as the most effective and environmentally benign technology, with tremendous potential to meet future global demands. However, identifying high-performance, economically viable materials for photoelectrodes which are building blocks of water splitting process, remains a significant challenge. In this regard, transition metal oxide photoanodes such as TiO2, WO3, BiVO4, ZnO, α-Fe2O3, etc. are potential candidates for efficient water splitting. Nonetheless, intrinsic barriers including limited light harvesting, poor charge separation/transport, and sluggish OER kinetics limit their practical application. To address these issues, zeolitic imidazolate frameworks, a class of unique materials belonging to the metal-organic frameworks family are emerging as a potential catalyst for the development of photoelectrodes owing to their large surface area, extensive redox-active sites, excellent thermal and chemical stability, and hierarchical porosity. This review highlights advancements in employing ZIF-8 and ZIF-67 catalysts to improve the PEC efficiency of established metal oxide semiconducting photoanodes, addressing a gap in the existing literature. For broader context, this review covers PEC water splitting fundamentals and advanced metal oxide/ZIF-based photoelectrode mechanisms, aiding next-generation PEC device design. The conversation about current challenges and future directions will provide new avenues for improving the ZIF-based PEC water splitting landscape.
Display omitted
•This review emphasizes the potential of ZIF-8 and ZIF-67 for enhancing PEC water splitting.•The fundamental redox reactions and PEC water splitting parameters are discussed.•The catalytic features of ZIFs to advance the efficiencies were highlighted.•Recent progress in metal oxide photoanode engineering via ZIFs is presented in-depth.•Current challenges and perspectives for future developments are outlined.
Design and construction of low‐cost electrocatalysts with high catalytic activity and long‐term stability is a challenging task in the field of catalysis. Metal‐organic frameworks (MOF) are promising ...candidates as precursor materials in the development of highly efficient electrocatalysts for energy conversion and storage applications. This review starts with a summary of basic concepts and key evaluation parameters involved in the electrochemical water‐splitting reaction. Then, different synthesis approaches reported for the cobalt‐based Zeolitic imidazolate framework (ZIF‐67) and its derivatives are critically reviewed. Additionally, several strategies employed to enhance the electrocatalytic activity and stability of ZIF‐67‐based electrocatalysts are discussed in detail. The present review provides a succinct insight into the ZIF‐67 and its derivatives (oxides, hydroxides, sulfides, selenides, phosphide, nitrides, telluride, heteroatom/metal‐doped carbon, noble metal‐supported ZIF‐67 derivatives) reported for oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and overall water splitting applications. Finally, this review concludes with the associated challenges and the perspectives on developing the best economic, durable electrocatalytic materials.
MOF‐derived electrocatalysts/electrodes have excellent prospects in energy storage and conversion systems. This paper presents an in‐depth review of the application of ZIF‐67‐derived electrocatalysts for OER, HER, and overall water splitting, highlighting experimental and computational results demonstrated in the literature. Recent progress in synthesis routes and strategies used to enhance the electrocatalytic activity of ZIF‐67 derived electrocatalysts is explicitly discussed.
•Fe-ZIF-derived hollow porous carbon nanofibers were successfully fabricated.•Fe-HPCNFs achieved a maximum RL of −46.9 dB at 2.0 GHz, an effective absorption bandwidth of 3 GHz with thickness of ...2.0 mm.•Fe-HPCNFs were hierarchical porous and self-supported, with uniformly dispersed Fe single atoms.
The nanomaterials with multiple components and various heterogeneous interfaces have been considered as preferred efficient electromagnetic wave (EMW) absorbers. In this paper, Fe atoms were bonded to a zeolitic imidazole framework (Fe-ZIF) and Fe-ZIF-derived hollow porous carbon nanofibers (Fe-HPCNFs) were prepared by the microfluid electrospinning method. The EMW absorption properties of carbon nanofibers (CNFs), Fe-ZIF-derived carbon nanofibers (Fe-CNFs), and Fe-ZIF-derived hollow porous carbon nanofibers (Fe-HPCNFs) were systematically studied. The results showed that Fe-HPCNFs has the best performance, when the thickness was only 2.0 mm, the Fe-HPCNFs achieved a minimum RL loss of −46.9 dB at 17.38 GHz, with an effective absorption bandwidth of 3 GHz. The Fe-HPCNF is a flexible, ultralightweight, self-supported material as a potential high-efficiency EMW absorber.
Display omitted
•The porous lamellar GO/Ni2ZnS4@NiCo2S4 was prepared using simple ZIF-8@ZIF-9 templating method.•The core–shell structure of graphene trimetallic sulfides was synthesized for the ...first time.•GO/Ni2ZnS4@NiCo2S4 inherits the high specific surface area of the ZIF template and the high pseudocapacitance of the sulfide.•High specific capacity of 2284F/g were achieved at the current density of 1 A/g.
Metal-organic frameworks (MOFs) have emerged as promising active electrode materials in supercapacitors for its controllable porous structure and excellent physio-chemical properties. However, the poor conductivities keep it from achieving its full capacitance potential, which greatly limits its practical application. Here, a facile pathway is reported to fabricate the GO/Ni2ZnS4@NiCo2S4 composite with large specific surface area and favorable electrical conductivity. Thanks to the novel tremella-like core–shell structure and high-efficient synergistic effects among multi-components, the designed GO/Ni2ZnS4@NiCo2S4 electrode shows a high specific capacitance of 2284 F/g at 1 A/g. Furthermore, the asymmetric supercapacitor fabricated by coupling GO/Ni2ZnS4@NiCo2S4 positive electrode with biological carbon negative electrode achieves a remarkable energy density of 120 Wh kg−1 at a power density of 750 W kg−1.
The novel functional superwettable materials for high‐efficiency oil/water separation are urgently required due to oil pollution in water body caused by oil tanker accidents, seabed oil production, ...and oil from refineries and petrochemical plants. Here, the superhydrophobic and superoleophilic zeolitic imidazolate framework‐L (ZIF‐L) mesh with antimicrobial effect was successfully fabricated by in‐situ growth, composed of vertically ZIF‐L with micro‐/nanodagger‐like structure and exhibited the water contact angle of 155.4 ± 1.8° and the oil contact angle of 0° in air. Furthermore, ZIF‐L was verified to have an excellent antimicrobial activity, which endowed ZIF‐L mesh with good antimicrobial performance. ZIF‐L mesh provided a permeation flux with 1.75 × 105 L m−2 hr−1 and 99.7% separation efficiency after 10 cycles operations for water mixtures with isooctane and presented optimal stability. Accordingly, the results demonstrated that ZIF‐L as a new material shows an attractive applied promise for oil/water separation in industry.
