The first alkali‐metal vanadium iodate fluoride, CsVO2F(IO3), with a novel 3D anionic framework, has been rationally designed and hydrothermally synthesized. The 3D VO2F(IO3)− framework in ...CsVO2F(IO3) is built from 0D Λ‐shaped cis‐VO3F(IO3)24− polyanions via corner‐sharing of oxo anions and bridging of the iodate groups. CsVO2F(IO3) displays both a strong second‐harmonic generation (SHG) 1.1 times as strong as KTiOPO4 (KTP) under 2.05 μm laser radiation and high laser‐induced damage threshold (LIDT) of 107.9 MW cm−2. This work provides a new route to design SHG crystals with stable 3D anionic structures from low‐dimensional structural building units.
From zero to threero: CsVO2F(IO3) is the first example of a 3D VO2F(IO3)− anionic framework built from 0D Λ‐shaped cis‐VO3F(IO3)24− units. The system shows a strong second‐harmonic generation (SHG), 1.1 times as strong as KTiOPO4 under 2.05 μm laser radiation and a high laser‐induced damage threshold of 107.9 MW cm−2.
Innovative cities that use Information and Communication Technologies (ICT) while guaranteeing that they meet current generations’ needs for life quality, operating efficiency, and competitive nature ...are known as Smart Sustainable Cities (SSCs). Green spaces and eco-friendly practices are integrated into the urban area to reduce pollution levels and CO2 emissions and protect the natural resources within the city. Apps for smart cities are designed to control traffic and respond to emergencies in real-time. Therefore, smart cities may be better equipped to react to challenges than those with a straightforward transaction processing relationship with their residents. Existing high-speed internet and underground wiring in major metro areas are both in need of replacement due to deterioration from decades of use. Although the availability of wireless broadband service is expanding, some parts of the country’s largest cities are still without it. In order to maintain cities in a sustainable fashion, there are several obstacles that must be faced. Congestion, a lack of funding for essential services, a lack of suitable accommodation, deteriorating infrastructure, and increasing air pollution are all common problems in cities. The major challenges such as the best use of urban buildings’ energy generation, storage, consumption, fossil fuel use, disregard for the environment, and limited internet technology (IT) architecture are all contributing factors in the city’s decline addressed in this research. Therefore, this paper proposes the social collaboration of renewable energy resources (SC-RER) technique to overcome the basic challenges described above. With the help of the proposed technique, local renewable energy sources can be used to their full potential. Smart block innovation (SBI) is used to make smart community planning mode. Energy-Efficiency (EE) model is framed to reduce the energy consumed significantly. As a result, it helps increase the method’s efficiency to gain a 95.4% maximum level, suitable for making sustainable smart cities.
Covalent organic frameworks have recently gained increasing attention in photocatalytic hydrogen generation from water. However, their structure-property-activity relationship, which should be ...beneficial for the structural design, is still far-away explored. Herein, we report the designed synthesis of four isostructural porphyrinic two-dimensional covalent organic frameworks (MPor-DETH-COF, M = H
, Co, Ni, Zn) and their photocatalytic activity in hydrogen generation. Our results clearly show that all four covalent organic frameworks adopt AA stacking structures, with high crystallinity and large surface area. Interestingly, the incorporation of different transition metals into the porphyrin rings can rationally tune the photocatalytic hydrogen evolution rate of corresponding covalent organic frameworks, with the order of CoPor-DETH-COF < H
Por-DETH-COF < NiPor-DETH-COF < ZnPor-DETH-COF. Based on the detailed experiments and calculations, this tunable performance can be mainly explained by their tailored charge-carrier dynamics via molecular engineering. This study not only represents a simple and effective way for efficient tuning of the photocatalytic hydrogen evolution activities of covalent organic frameworks at molecular level, but also provides valuable insight on the structure design of covalent organic frameworks for better photocatalysis.
As one of the most critical approaches to resolve the energy crisis and environmental concerns, carbon dioxide (CO2) photoreduction into value‐added chemicals and solar fuels (for example, CO, HCOOH, ...CH3OH, CH4) has attracted more and more attention. In nature, photosynthetic organisms effectively convert CO2 and H2O to carbohydrates and oxygen (O2) using sunlight, which has inspired the development of low‐cost, stable, and effective artificial photocatalysts for CO2 photoreduction. Due to their low cost, facile synthesis, excellent light harvesting, multiple exciton generation, feasible charge‐carrier regulation, and abundant surface sites, semiconductor quantum dots (QDs) have recently been identified as one of the most promising materials for establishing highly efficient artificial photosystems. Recent advances in CO2 photoreduction using semiconductor QDs are highlighted. First, the unique photophysical and structural properties of semiconductor QDs, which enable their versatile applications in solar energy conversion, are analyzed. Recent applications of QDs in photocatalytic CO2 reduction are then introduced in three categories: binary II–VI semiconductor QDs (e.g., CdSe, CdS, and ZnSe), ternary I–III–VI semiconductor QDs (e.g., CuInS2 and CuAlS2), and perovskite‐type QDs (e.g., CsPbBr3, CH3NH3PbBr3, and Cs2AgBiBr6). Finally, the challenges and prospects in solar CO2 reduction with QDs in the future are discussed.
Carbon dioxide (CO2) photoreduction is regarded as an attractive pathway to produce value‐added chemicals and fuels. Recent advances in CO2 photoreduction via semiconductor quantum dots (QDs) in three categories are reviewed: II–VI, I–III–VI, and perovskite‐type QDs. Additionally, current challenges and prospects for QD‐photocatalyzed CO2 reduction are discussed.
Herein the novel tetraphenylethylene (TPE) derivative 1 was designed with an integration of aggregation‐induced emission (AIE), multi‐state mechanochromism and self‐recovery photochromism. The ...molecule was susceptible to grinding, heating and vapor fuming and showed corresponding transition of its emission colors. The heated powder or single crystal of 1 exhibited reversible photochromism. After a short period of UV irradiation, it showed a bright red color, but recovered to its original white appearance within 1 min. The photochromism is due to the formation of photocyclization intermediates upon UV irradiation, while the eversible mechanochromism is attributed to the weak molecular interactions derived from head‐to‐tail stacking of the molecules. This reversible multi‐state, high‐contrasted and rapid responsive mechanochromic and photochromic property cooperatively provide double enhancement of a multimode guarantee in advanced anti‐counterfeiting.
Forgery‐proof: A novel AIE molecule 1 is designed with high‐contrasted and multi‐state mechanochromic and photochromic properties. Based on these properties, 1 shows great potential for application in advanced multidimensional anti‐counterfeiting, which was demonstrated by fabrication of a model banknote.
Semiconducting quantum dots (QDs) have recently triggered a huge interest in constructing efficient hydrogen production systems. It is well established that a large fraction of surface atoms of QDs ...need ligands to stabilize and avoid them from aggregating. However, the influence of the surface property of QDs on photocatalysis is rather elusive. Here, the surface regulation of CdSe QDs is investigated by surface sulfide ions (S2−) for photocatalytic hydrogen evolution. Structural and spectroscopic study shows that with gradual addition of S2−, S2− first grows into the lattice and later works as ligands on the surface of CdSe QDs. In‐depth transient spectroscopy reveals that the initial lattice S2− accelerates electron transfer from QDs to cocatalyst, and the following ligand S2− mainly facilitates hole transfer from QDs to the sacrificial agent. As a result, a turnover frequency (TOF) of 7950 h−1 can be achieved by the S2− modified CdSe QDs, fourfold higher than that of original mercaptopropionic acid (MPA) capped CdSe QDs. Clearly, the simple surface S2− modification of QDs greatly increases the photocatalytic efficiency, which provides subtle methods to design new QD material for advanced photocatalysis.
To unravel how surface sulfide ions (S2−)regulate photocatalytic hydrogen evolution of CdSe quantum dots (QDs), the different roles of introduced S2− on QDs are revealed. The results show that S2− at an earlier stage grows into the lattice and accelerates electron transfer, while afterward the S2− works as ligands and promotes hole transfer, and thus greatly improves the photocatalytic hydrogen evolution efficiency.
Social networking applications have been designed as innovative technologies used by the higher education section to enhance the acquisition of literacy skills, driving learners to engage in online ...learning platforms. Such tools such as social networking have also been proven to facilitate teaching and learning; therefore, educational programs and universities are increasingly making use of networking sites to form connections with students and to offer online instructional content. This trend has placed questions, regarding the effect of social media on language learning and its potential use as an effective instructional tool. The constructive role of enjoyment did not obtain equal academic consideration in the EFL learning milieu until Positive Psychology was presented to L2 education. Using social networking, users find online tasks appealing and experience the enjoyment that, in turn, impacts their behavioral intention to use them positively. Commitment is another factor that refers to the degree to which students are involved in learning enthusiastically. This construct concerns the extent to which students are loyal to learning, textbooks, and class etiquette. As it contributes to the quality of learning, it is considered a prerequisite for students’ academic success and educational attainment. Based on the role of the above-mentioned constructs in language learning, the present review tries to consider the role of social networking in boosting EFL students’ commitment and enjoyment. Consequently, some implications are presented for academic stakeholders in the quest of considering the role of social networking in language education.
Floccules are another major form of microbial aggregates in aerobic granular sludge systems. Previous studies mainly attributed the persistence of floccules to their relatively faster nutrient uptake ...and higher growth rate over aerobic granules; however, they failed to unravel the underlying mechanism of the long‐term coexistence of these two aggregates. In this work, the existence and function of the floccules in an aerobic granule‐dominated sequencing batch reactor were investigated from the view of quorum sensing (QS) and quorum quenching (QQ). The results showed that though the floccules were closely associated with the granules in terms of similar community structures (including the QS‐ and QQ‐related ones), they exhibited a relatively higher QQ‐related activity but a lower QS‐related activity. A compatible proportion of floccules might be helpful to maintain the QS‐related activity and keep the granules stable. In addition, the structure difference was demonstrated to diversify the QS‐ and QQ‐related activities of the floccules and the aerobic granules. These findings could broaden our understanding of the interactions between the coexistent floccules and granules in aerobic granule‐dominated systems and would be instructive for the development of the aerobic granular sludge process.
Head and neck squamous cell carcinoma (HNSCC) causes much health and economic burden, and the therapeutic results must be improved. Glucose metabolism is an essential component of tumor metabolism ...and is instrumental in its development. Glucose transporter types (GLUTs) can uptake glucose from the extracellular matrix (ECM), regulating cellular metabolism in several cancers. However, the function of different GLUT proteins in HNSCC remains unclear. To clarify the role of GLUTs in HNSCC, several open-access online databases (Oncomine, GEPIA, Kaplan-Meier, cBioPortal, GeneMANIA, and TIMER) were used to evaluate the differential expression, clinical significance, genetic alteration, and relative immune cell infiltration. The expression of GLUTs was detected in clinical patient samples by immunohistochemistry. The mRNA level of SLC2A1/3 significantly increased in HNSCC, while SLC2A4 reduced. SLC2A3 was related to the advanced clinical stage and short overall survival (OS) in HNSCC. Also, higher SLC2A1/2 mRNA expression was related to shorter OS in HNSCC patients. The expression of GLUTs was related to diverse immune cells, including B cells, CD4
T cells, CD8
T cells, dendritic cells (DCs), macrophages, and Treg cells in HNSCC. Moreover, the high expression of GLUTs was demonstrated by immunohistochemistry in patient tissues. GLUTs might have a potential role in HNSCC's progression and development. Therefore, the current findings might offer a novel perception for selecting GLUT family prognostic markers and treatment for HNSCC patients.
Light‐driven multielectron redox reactions (e.g., hydrogen (H2) evolution, CO2 reduction) have recently appeared at the front of solar‐to‐fuel conversion. In this Minireview, we focus on the recent ...advances in establishing semiconductor quantum dot (QD) assemblies to enhance the efficiencies of these light‐driven multielectron reduction reactions. Four models of QD assembly are established to promote the sluggish kinetics of multielectron transfer from QDs to cocatalysts, thus leading to an enhanced activity of solar H2 evolution or CO2 reduction. We also forecast the potential applications of QD assemblies in other multielectron redox reactions, such as nitrogen (N2) fixation and oxygen (O2) evolution from H2O.
Join the dots: This Minireview focuses on the recent advances in constructing semiconductor quantum dot (QD) assemblies to enhance the efficiencies of light‐driven multielectron redox reactions, such as H2 evolution and CO2 reduction. Furthermore, their potential applications in N2 fixation and H2O oxidation is suggested.
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