Zirconium‐based metal‐organic framework materials (Zr−MOFs) have more practical usage over most conventional benchmark porous materials and even many other MOFs due to the excellent structural ...stability, rich coordination forms, and various active sites. However, their mass‐production and application are restricted by the high‐cost raw materials, complex synthesis procedures, harsh reaction conditions, and unexpected environmental impact. Based on the principles of “Green Chemistry”, considerable efforts have been done for breaking through the limitations, and significant progress has been made in the sustainable synthesis of Zr−MOFs over the past decade. In this review, the advancements of green raw materials and green synthesis methods in the synthesis of Zr−MOFs are reviewed, along with the corresponding drawbacks. The challenges and prospects are discussed and outlooked, expecting to provide guidance for the acceleration of the industrialization and commercialization of Zr−MOFs.
The production and application of Zirconium‐based metal‐organic framework materials are restricted by numerous factors. By embracing green chemistry, green raw materials and green synthesis methods are the keys in sustainable synthesis of Zr−MOFs over last decade. This review summarizes the achievements and looks forward to the future industrialization and commercialization of Zr−MOFs.
Fabrication of hybrid MOF‐on‐MOF heteroarchitectures can create novel and multifunctional platforms to achieve desired properties. However, only MOFs with similar crystallographic parameters can be ...hybridized by the classical epitaxial growth method (EGM), which largely suppressed its applications. A general strategy, called internal extended growth method (IEGM), is demonstrated for the feasible assembly of MOFs with distinct crystallographic parameters in an MOF matrix. Various MOFs with diverse functions could be introduced in a modular MOF matrix to form 3D core–satellite pluralistic hybrid system. The number of different MOF crystals interspersed could be varied on demand. More importantly, the different MOF crystals distributed in individual domains could be used to further incorporate functional units or enhance target functions.
A general strategy, the internal extended growth method (IEGM), was applied to design modular hierarchically structured MOF composites, thereby overcoming the limitation of lattice matching. The number of MOF crystals interspersed and the size of the MOF matrix can be well‐controlled. IEGM can optimize the design of novel multicompositional MOFs systems with great flexibility. TTIP=Ti(OiPr4), BDC=benzenedicarboxylic acid.
Recently, reactive iron species (RFeS) have shown great potential for the selective degradation of emerging organic contaminants (EOCs). However, the rapid generation of RFeS for the selective and ...efficient degradation of EOCs over a wide pH range is still challenging. Herein, we constructed FeN4 structures on a carbon nanotube (CNT) to obtain single-atom catalysts (FeSA-N-CNT) to generate RFeS in the presence of peroxymonosulfate (PMS). The obtained FeSA-N-CNT/PMS system exhibited outstanding and selective reactivity for oxidizing EOCs over a wide pH range (3.0–9.0). Several lines of evidences suggested that RFeS existing as an FeN4O intermediate was the predominant oxidant, while SO4 ·– and HO· were the secondary oxidants. Density functional theory calculation results revealed that a CNT played a key role in optimizing the distribution of bonding and antibonding states in the Fe 3d orbital, resulting in the outstanding ability of FeSA-N-CNT for PMS chemical adsorption and activation. Moreover, CNT could significantly enhance the reactivity of the FeN4O intermediate by increasing the overlap of electrons of the Fe 3d orbital, O 2p orbital, and bisphenol A near the Fermi level. The results of this study can advance the understanding of RFeS generation in a heterogeneous system over a wide pH range and the application of RFeS in real practice.
•Possibility of high-power output by piezo-coupled engineering structures is discussed.•Methods and mechanism improving piezoelectric power output are summarized.•Works with W and higher power output ...by engineering structural design are reviewed.
Nowadays, with more electrical devices developed and applied in wide fields, efficient electrical energy generation is always one of the front-end and practical topics in engineering research. To disclose the possibility of obtaining high-power output from piezoelectric mechanism in the engineering structures, this study conducts a review of piezoelectric energy harvesting techniques from a structural design point of view. Piezoelectric power generation of these techniques can be significantly enhanced by increasing the operation frequency of piezoelectric materials and the strain level on them (up to Watt level). In this paper, following the general introduction of new energy solution requirements and piezoelectric mechanisms, novel ideas on piezoelectric energy harvesting from ambient vibration and natural resources are briefly reviewed. We then summarized and discussed the methodologies and mechanisms used to increase piezoelectric power generation and energy harvesting efficiency in detail. Following these methods, current studies on high-power piezoelectric harvesters are reviewed, described, and summarized to demonstrate the potential high-power generation from piezoelectricity. Taking advantage of the simple mechanism and design flexibility of the piezoelectric energy generation devices, additive manufacturing can be used to fabricate specially shaped piezoelectric meta-materials to further increase the strain and frequency applied to piezoelectric elements for obtaining higher energy harvesting efficiency in the near future.
Voltage-gated ion channels are integral membrane proteins that respond to changes in membrane potential with rapid variations in membrane permeability to ions ....
Wolff's law and the Utah Paradigm of skeletal physiology state that bone architecture adapts to mechanical loads. These models predict the existence of a mechanostat that links strain induced by ...mechanical forces to skeletal remodeling. However, how the mechanostat influences bone remodeling remains elusive. Here, we find that Piezo1 deficiency in osteoblastic cells leads to loss of bone mass and spontaneous fractures with increased bone resorption. Furthermore, Piezo1-deficient mice are resistant to further bone loss and bone resorption induced by hind limb unloading, demonstrating that PIEZO1 can affect osteoblast-osteoclast crosstalk in response to mechanical forces. At the mechanistic level, in response to mechanical loads, PIEZO1 in osteoblastic cells controls the YAP-dependent expression of type II and IX collagens. In turn, these collagen isoforms regulate osteoclast differentiation. Taken together, our data identify PIEZO1 as the major skeletal mechanosensor that tunes bone homeostasis.
A general one‐step in situ pyrolysis route for the construction of metal–organic frameworks encapsulating superparamagnetic γ‐Fe2O3 NPs dispersed in the confined cavities of MOFs homogeneously is ...described. The integration of γ‐Fe2O3 NPs or clusters into MOFs can endow these porous materials with superparamagnetic element. By the combination of the thermal stability of MOFs and pyrolysis of metal triacetylacetonate complex at matched conditions, the porous structure of MOFs are well maintained while the size‐induced superparamagnetic property of nano γ‐Fe2O3 is obtained. As a proof of concept, both the γ‐ Fe2O3@ZIF‐8 and γ‐Fe2O3@MIL‐53(Al) were successfully prepared, and the latter was chosen to demonstrate its potential drug delivery as a magnetic MOF.
A metal–organic framework (MOF) with superparamagnetic properties is successfully fabricated. It is demonstrated that the encapsulation of biocompatible and nontoxic γ‐Fe2O3 into the framework of the MOF endows the resulting materials with additional superparamagnetic properties, which can be facilely used as a multifunctional nanocarrier to afford a new type of magnetic MOF materials.
•AWSI based on blue-green water and water footprint (WF) framework is established.•Blue water dominates in water resources while blue WF accounts for 12.7% of the total.•Water scarcity was aggravated ...from 1999 to 2014 in agricultural production of China.•The AWSI is suitable for water scarcity evaluations, particularly in arid area.
Display omitted
An indicator, agricultural water stress index (AWSI), was established based blue-green water resources and water footprint framework for regional water scarcity in agricultural production industry evaluation. AWSI is defined as the ratio of the total agricultural water footprint (AWF) to water resources availability (AWR) in a single year. Then, the temporal and spatial patterns of AWSI in China during 1999–2014 were analyzed based on the provincial AWR and AWF quantification. The results show that the annual AWR in China has been maintained at approximately 2540Gm3, of which blue water accounted for >70%. The national annual AWF was approximately 1040Gm3 during the study period and comprised 65.6% green, 12.7% blue and 21.7% grey WFs The space difference in both the AWF for per unit arable land (AWFI) and its composition was significant. National AWSI was calculated as 0.413 and showed an increasing trend in the observed period. This index increased from 0.320 (mid-water stress level) in 2000 to 0.490 (high water stress level) in the present due to the expansion of the agricultural production scale. The Northern provinces, autonomous regions and municipalities (PAMs) have been facing high water stress, particularly the Huang-Huai-Hai Plain, which was at a very high water stress level (AWSI>0.800). Humid South China faces increasingly severe water scarcity, and most of the PAMs in the region have converted from low water stress level (AWSI=0.100–0.200) to mid water stress level (AWSI=0.200–0.400). The AWSI is more appropriate for reflecting the regional water scarcity than the existing water stress index (WSI) or the blue water scarcity (BWS) indicator, particularly for the arid agricultural production regions due to the revealed environmental impacts of agricultural production. China should guarantee the sustainable use of agricultural water resources by reducing its crop water footprint.
PDF
