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[Display omitted] • Hydrophobic eutectogel is facilely produced through the polymerization of hydrophobic monomers in a hydrophobic DES. • The hydrophobic eutectogel shows outstanding water resistance (water contact angle over 110°) and extraordinary durability (over 1000 testing cycles) underwater. • Hydrophobic eutectogel can be utilized as strain and pressure sensors underwater. • Hydrophobic eutectogel sensors can transmit information through Morse code, performing as a underwater communicator. Eutectogels derived from deep eutectic solvents (DESs) exhibit great potential for the fabrication of flexible sensors. However, the hygroscopicity of eutectogels hinders their applications in underwater sensing. In this work, a hydrophobic eutectogel with exceptional long-term underwater stability is produced through one-step polymerization of lauryl methacrylate and glycidyl methacrylate in a hydrophobic DES. The hydrophobic gel network and hydrophobic DES fulfill the eutectogel with outstanding water resistance (water contact angle > 110°) and excellent mechanical properties in an aqueous environment, thus leading to extraordinary durability (over 1000 testing cycles). Additionally, based on this eutectogel, underwater strain and pressure sensors with high sensitivity, rapid responsiveness, and superior durability were fabricated for accurate real-time monitoring of human activity. Furthermore, it has been demonstrated that the eutectogel sensor can transmit information through Morse code, performing as a wearable underwater communicator. This research provides an exemplary way for a demonstration method of hydrophobic eutectogel for durable underwater applications. [ABSTRACT FROM AUTHOR]

[Display omitted] Excessive CO 2 emissions have contributed to global environmental issues, driving the development of CO 2 capture adsorbents. Among various candidates, metal–organic frameworks (MOFs) are considered the most promising due to their unique microporous structure. Herein, a series of partially interpenetrated MOFs named UPC-XX were built to investigate the continuous enhancement in CO 2 capture performance via synergistic effects from functional group, pore size, and steric-hindrance using theoretical calculations. It's showed that the introduction of functional groups improved the structure polarity and created more adsorption sites, thus, enhanced CO 2 capture capacity. The pore size modification augments the exposure of adsorption sites to mitigate the negative impact of pore space and surface area reduction caused by the introduction of functional groups, thereby further increasing the CO 2 capture capacity. The steric-hindrance effect optimized the adsorption sites distribution, which hasn't been considered in the previous two regulation strategies, thus, further increased the CO 2 capture capacity. The results underscore UPC-MOFs as outstanding adsorbent materials, among the UPC-MOFs, UPC-OSO 3 -steric exhibited the highest CO 2 capture capacity of 12.69 mmol/g with selectivities of 1142.41 (CO 2 over N 2) and 507.42 (CO 2 over CH 4) at 1.0 bar, 298 K. And the synergistic effect mechanisms of functional group, structure size, and steric hindrance were elucidated through theoretical calculations analyzing pore characteristics, gas distribution, isosteric heat, and van der Waals/Coulomb interactions. [ABSTRACT FROM AUTHOR]

• Fluorescent carbon polymer materials are prepared by mixing H 2 SO 4 and DETA at room temperature. • The samples possess unique hollow nanospheres structure with strong fluorescence property. • Such fluorescent carbon polymer hollow spheres are used as peroxidase mimics for H 2 O 2 detection. Fluorescent carbon polymer nanomaterials driven by their important various applications are promising, however, their scalable usages are still hindered by the lack of facile and effective synthesis approaches. Herein, a rapid and facile approach is demonstrated for the preparation of fluorescent carbon polymer hollow spheres (CPHSs), which were synthesized by directly mixing concentrated sulfuric acid (H 2 SO 4) and diethylenetriamine (DETA) at room temperature. Notably, both the solid powders and aqueous dispersion of CPHSs possess the fluorescence properties, similar with the reported carbon polymer dots. The formation of CPHSs could be attributed to the polymerization of DETA in the presence of H 2 SO 4. The present strategy is universal and fluorescent nanomaterials could also be obtained by using hexamethylenetetramine or polyethylenepolayamine as precursors with the aid of concentrated H 2 SO 4. Most importantly, the CPHSs possess peroxidase-like activity and can catalyze oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to its one-electron oxidation product, providing a new method for colorimetric detection of H 2 O 2. [ABSTRACT FROM AUTHOR]

Here, we report an organometallic chemistry-assisted method for modification of zinc oxide (ZnO) nanoparticles by tin oxide (SnO 2) nanoparticles, providing a novel and efficient approach for preparation of metal oxides-based heterojunction. The SnO 2 /ZnO heterojunctions were prepared by modification of ZnO nanoparticles with (CH 3) 2 SnCl 2 through organometallic chemistry reaction firstly, and subsequently thermal treatment in air atmosphere. The combined characterizations indicate the successful formation of ZnO/SnO 2 heterojunctions with controllable surface oxygen vacancy concentrations by optimizing organometallic chemistry reactions. Most importantly, ZnO-Sn-0.75-based NO 2 sensor delivers the response of 14.3 toward 0.5 ppm NO 2 at 190 °C with response time of 100 s and recovery time of 101 s. It is also found that ZnO-Sn-0.75 sample exhibits better NO 2 sensing performances than ZnO nanoparticles and other ZnO-Sn samples (ZnO-Sn-0.50, and ZnO-Sn-1.0). The excellent sensing performances of ZnO-Sn-0.75 are attributed to the synergistic effect n - n heterojunction and controllable surface oxygen species. The present work opens a generalized avenue for facile, cheap and mass production of transition metal oxides-based heterojunctions for various applications. [ABSTRACT FROM AUTHOR]

Circular RNAs are covalently closed and non-coding in eukaryotes, which have tissue- specific and temporal-specific expression patterns whose biogenesis is regulated by transcription and splicing. Most circular RNAs are localized in the cytoplasm. The sequences and protein-binding elements of circular RNAs facilitate circular RNAs in exerting biological functions through complementary base pairing, regulating protein function or self-translation. Recent studies have revealed that N6-Methyladenosine (m6A), a prevalent post-transcriptional modification, can affect the translation, localization, and degradation of circular RNAs. Cutting-edge research into circular RNAs have benefitted from the development of high-throughput sequencing technology. Furthermore, the expansion of novel research methods has promoted progress into circular RNA research. [ABSTRACT FROM AUTHOR]

Cobalt oxide (Co 3 O 4 )-based materials have been extensively investigated as efficient electrocatalysts for non-enzymatic glucose biosensing. The proper tuning the structure of Co 3 O 4 -based materials could improve sensing performances for glucose detection. Herein, we have developed a combined self-assembly and calcination method to prepare nanoparticles-assembled Co 3 O 4 nanosheets, which exhibit good sensing performances for glucose biosensing. The Co 3 O 4 nanosheets were prepared by the following three steps: (i) the Co 2+ modified graphene oxide (GO) was prepared by the self-assembly of Co 2+ and GO in aqueous solution firstly, and then Co 2+ modified GO film was obtained by vacuum filtration method; (ii) after calcination of Co 2+ modified GO film in N 2 atmosphere, Co 3 O 4 nanoparticles modified reduced GO (RGO) was obtained; (iii) finally, nanoparticles-assembled Co 3 O 4 nanosheets were obtained by calcination of Co 3 O 4 modified RGO in air to remove RGO template. Most importantly, Co 3 O 4 nanosheets exhibit good electrocatalytic activity for oxidation of glucose, leading to high-performance glucose sensor. The detection limit and linear range of Co 3 O 4 nanosheets-based glucose sensor in the present work are 0.15 μM, and 1–50 μM, respectively. Furthermore, such sensor also shows excellent selectivity for glucose detection, compared to the commonly interfering species including dopamine, and uric acid. [ABSTRACT FROM AUTHOR]

The construction of C–C bonds and degradation of chemical warfare agents (CWAs) are two central organic conversions for future sustainable development. Herein, two remarkable silver-containing polyoxomolybdates-based hybrids (Ag-POMos), [Ag(L)(H 2 O) 2 ] 2 [HPMo 12 O 40 ] (1) and [Ag 2 (L) 2 ] 2 [HPMo 10 V 2 O 40 ]·4DMSO (2) (L ​= ​4,6-bis(2-pyridyl)-2-aminopyrimidine) were designed and prepared by using silver cation, polyoxomolybdates and multiple N-donors ligand (L). The structure of compound 1 is constructed from an independent Ag center and a keggin-type POMs; compound 2 is composed of two independent Ag centers and a keggin-type POMs, which displays intriguing POM-incorporated 1-D chain structure with hydrogen bonding. Additionally, Ag-POMos catalysts can be severed as the efficient bifunctional catalysts for the three-component Mannich reaction to achieve the construction of C–C bonds and decontamination of sulfur mustard 2-chloroethyl ethyl sulfide (CEES). As bifunctional heterogeneous catalyst, particularly compound 2 , exhibits satisfying catalytic performances in the Mannich reaction (conv. 99%; sele. 99%) and the oxidation of CEES (conv. 96%; sele. 96%). Notedly, after three runs, compound 2 maintains excellent catalytic properties, demonstrating its remarkable cycling stability. 1. Two novel inorganic-organic silver-polyoxomolybdates hybrids were synthesized for the first time and routinely characterized.2. The compounds can be severed as efficient bifunctional catalysts (functions of Lewis acid catalysis and oxidation catalysis) for the construction of the C–C bond and decontamination of sulfur mustard 2-chloroethyl ethyl sulfide (CEES).3. The molecular compound 2 has good cycling stability, after three continuous runs, the conversion and selectivity have no obvious decrease. [Display omitted] • Designed and synthesis of four- and five-coordinate silver-polyoxomolybdate clusters with bifunctional catalytic properties. • These bifunctional catalysts can efficiently catalyze both Mannich reaction and degradation of sulfur mustard simulant under mild conditions. • The bifunctional catalysts have wide substrate applicability and good catalytic performance. [ABSTRACT FROM AUTHOR]

As a special ecosystem in cities, urban wetland parks have important environmental regulation and social service functions. This paper proposes a new methodology of urban wetland planning and management based on the vulnerability of the ecological environment. The Jixi National Wetland Park (JNWP) was taken as the research area to analyze the ecological, geological and environmental factors that affect urban wetlands. A remote sensing image, digital elevation model, and environmental quality interpolation processing were used to generate the factor layer, and a comprehensive evaluation index system was established. The fuzzy Delphi analytic hierarchy process (FDAHP) method was used to calculate the comprehensive weight of each evaluation factor. A model to evaluate the ecological environment vulnerability of the JNWP was established. Then, an improved k-means clustering algorithm was used to classify the ecological environment of the study area. The ecological environment vulnerability of the wetland was evaluated. The results showed that the vulnerability of the ecological environment in the study area could be divided into five levels, including very low, low, medium, high and very high vulnerability areas. According to the vulnerability level and the results of k-means++ cluster analysis, the JNWP is divided into five areas. The wetland buffer zone is the main factor that determines the distribution of ecological environment vulnerability in urban wetlands. However, cultivated land development and ecological environmental restoration are the main factors that determine the evolution of ecological environment vulnerability in urban wetlands. The FDAHP and geographic information systems (GIS), combined with cluster analysis, are effective methods to evaluate the vulnerability of the ecological environment of urban wetlands, which provides a scientific and accurate methodology for the management and sustainable development of urban wetlands. [Display omitted] • A new methodology was developed to quantify the vulnerability of urban wetlands. • Multi-sources data were used to extract vulnerability factors. • The vulnerability assessment considers ecological, geological and environmental aspects. • Urban planning affects vulnerability more than geological conditions and natural environment. • Different vulnerable areas and ecological environment types have different planning strategies. [ABSTRACT FROM AUTHOR]

Abstract: An aqueous dispersion of reduced graphene oxide (rGO) has been successfully prepared via chemical reduction of graphene oxide (GO) by hydrazine hydrate in the presence of aniline for the first time. The noncovalent functionalization of rGO by aniline leads to a rGO dispersion that can be very stable for several months without the observation of any floating or precipitated particles. Several analytical techniques including Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) have been used to characterize the resulting rGO. Taking advantages of the fact reducing ability of aniline toward AgNO3, we further demonstrated the subsequent decoration of rGO with Ag nanoparticles (AgNPs) by in situ chemical reduction of silver salts. It was found that such AgNP/rGO nanocomposites exhibit good catalytic activity toward the reduction of hydrogen peroxide (H2O2), leading to an enzymeless sensor with a fast amperometric response time of less than 2s. The linear detection range is estimated to be from 100μM to 80mM (r =0.9991), and the detection limit is estimated to be 7.1μM at a signal-to-noise ratio of 3. [Copyright &y& Elsevier]

Abstract: We report the design and synthesis of folate–poly(ethylene glycol)–polyamidoamine (FPP)-functionalized CdSe/ZnS quantum dots (QDs), in which the QD plays a key role in imaging, whereas the folate–poly(ethylene glycol) (PEG) conjugates of the polyamidoamine (PAMAM) dendrimer serve as a system targeted to folate receptors in tumor cells. Dendrimer ligands such as folate–PEG grafted PAMAM of generation 3.5 are found to encapsulate and solubilize luminescent QDs through direct ligand-exchange reactions. Because of membrane expression of FA receptors in tumor cells, this class of ligand-exchanged QDs is able to target tumor cells. We have evaluated FPP-coated QDs and QDs without folate in HeLa cells and shown that cellular uptake of FPP-coated QDs is more significant than that non folate QDs in vivo imaging experiment. In particular, QDs coated with FPP are initially bound to tumor cell surfaces, followed by slow endosomal escape and release into the tumor cells. These insights are important for the design and development of nanoparticle agents for optical detection of tumor cells and bio-imaging. [ABSTRACT FROM AUTHOR]

Abstract: Mesoporous silica and carbon materials have been successfully synthesized via a novel calcination induced phase separation of organic/inorganic hybrids prepared from solvothermal polymerization of polyvinyl alcohol (PVA) and tetraethyl orthosilicate (TEOS) in dimethyl sulfoxide (DMSO). Combined characterizations of XRD, nitrogen isotherms, and TEM techniques show that the samples have worm-like mesostructures with uniform pore size distributions and large BET surface areas. 1H NMR spectra reveal that ethanol was generated after the solvothermal treatments, indicating the polymerization of PVA and TEOS. Open mesopores of the desired silicas or carbons could be fabricated by calcining the hybrids in air and nitrogen, respectively. This route might open a new methodology to synthesize mesoporous materials. [Copyright &y& Elsevier]

Abstract: The ORF3 protein of porcine circovirus type 2 (PCV2) causes apoptosis in virus-infected cells and is not essential for virus replication. The ORF3 protein plays an important role in the pathogenesis of the PCV2 infection in mouse models and SPF piglets. The ORF3 protein interacts with the porcine homologue of Pirh2 (pPirh2), a p53-induced ubiquitin–protein E3 ligase, which regulates p53 ubiquitination. Here, we present our study analyzing the details of the molecular interaction between these three factors. Our experiments, in vitro and in vivo, show that ORF3 protein competes with p53 in binding to pPirh2. The amino acid residues 20 to 65 of the ORF3 protein are essential in this competitive interaction of ORF3 protein with pPirh2 over p53. The interaction of ORF3 protein with pPirh2 also leads to an alteration in the physiological cellular localization of pPirh2 and a significant reduction in the stability of pPirh2. These events contribute to the deregulation of p53 by pPirh2, leading to increased p53 levels and apoptosis of the infected cells. [Copyright &y& Elsevier]

This study examines the 4 typical natural plant communities at the coastal waterfront of Jiaozhou Bay. Based on field survey and sampling, laboratory analysis, application of classical statistical methods and the requirements for urban ecological preservation and data restoration in IoT engineering technology, this study investigates the diversity pattern of the 4 natural plant communities, i.e. Phragmitesaustralis , Suaeda salsa , Setariaviridis and Conyzacanadensis , analyzes the characteristics of the petroleum pollution suffered by these 4 natural plant communities and the soil at the coastal waterfront of Jiaozhou Bay. By investigating the impact on the natural regulation ability of the natural ecosystem, species and habitat, this study provides the basis for protection of the natural plant communities in the petroleum polluted area and for the design of plants arrangement in ecological restoration in the site and provides the support for application of IoT technology in urban ecosystem establishment and urban ecological restoration. Findings: (1) During investigation of 30 quadrats of the plant communities in the petroleum polluted area at coastal waterfront of Qingdao, 74 plant species have been discovered.They belong to 12 families, where Chenopodiaceae, Poaceae and Compositae are dominant families and account for 9.09%, 20.45% and 38.63% respectively; Phragmitesaustralis , Suaeda salsa , Conyza canadensis and Setariaviridis communities are all herbosa, their species composition is quite simplex and most of them are in monodominant community patch; (2) The Conyzacanadensis community has the largest Shannon-Wiener diversity index, Patrick richness index and Simpson dominance index, which are 2.115, 1.930 and 1.228 respectively; in terms Pielou evenness index, the rank is Phragmitesaustralis > Conyzacanadensis > Setariaviridis > Suaeda salsa , which are 1.056, 0.907, 0.877 and 0.661; (3) According to the result of data analysis, the petroleum polluted area at coastal waterfront of Jiaozhou Bay has average total salt content 0.626%, average PH 8.067 and average petroleum hydrocarbons content 69.306 mg/kg.According to the result of difference examination of different plant communities, the total salt, PH and petroleum hydrocarbons content in the soil at the coastal waterfront Jiaozhou Bay are the main factors that affect the distribution of plant communities in that area (P < 0.05), and the petroleum hydrocarbons content in the soil has significant impact on the distribution of the communities (P < 0.01).(4) In this study, the petroleum hydrocarbon tolerance degrees of the 4 typical tolerant plant communities are ranked as Conyzacanadensis > Suaeda salsa > Setariaviridis > Phragmitesaustralis.In the soil environment with light (Level Ⅰ) and severe (Level Ⅳ) petroleum hydrocarbon pollution, the indexes of Suaeda salsa and Conyzacanadensis are optimal among the communities; the indexes of Phragmitesaustralis and Setariaviridis are optimal in the soil environment with Level Ⅱ and Level Ⅲ petroleum hydrocarbon pollution and can grow better in that environment. • Oil pollution concentration on the influence of the natural plant community off the coast of the jiaozhou bay has been studied. • This study investigates natural plant communities along the coastal line of Jiaozhou Bay and simulate oil pollution in soil. • Results deal with oil pollution ecological landscape plant configuration mode with popularity and significance. [ABSTRACT FROM AUTHOR]

The plant community is the basic landscape unit of the coastal green space. The study of the oil-contaminated coastal green space plant community has an important role in improving the landscape quality and aesthetics of the coastal green space. This article takes the oil pollution shoreline of Jiaozhou Bay as an entry point to build a plant community landscape evaluation model, analyzes and evaluates the most scenic plant community types in the coastal area of Qingdao Jiaozhou Bay in order to provide scientific basis for the plant community landscape configuration along the oil polluted coastline of Jiaozhou Bay, and provide reference for the evaluation and construction of plant community landscape in other cities. • The plant community is the basic landscape unit of the coastal green space. • Oil-contaminated coastal green space plant community has an important role in improving the landscape quality. • The configuration has significance for landscape evaluation and construction of plant communities in coastal green spaces. [ABSTRACT FROM AUTHOR]

The α-Fe 2 O 3 /SnO 2 -RGO-15 possessed a competitive sensing performance with a high response of 7.4 towards 1 ppm NO 2 at room temperature. [Display omitted] As promising sensing materials, reduced graphene oxide (RGO)-based nanomaterials have drawn considerable attention in the fields of gas monitoring owing to their low operating temperature. However, constructing RGO-based room-temperature gas sensors possessing ppb-level limit of detection with high sensitivity remains challenging. In this work, a series of highly sensitive NO 2 sensors were fabricated using α-Fe 2 O 3 and SnO 2 co-decorated RGO hybrids (designated as α-Fe 2 O 3 /SnO 2 -RGO) as sensing materials. They were rationally synthesized by a one-pot hydrothermal method. Compared to SnO 2 modified RGO hybrids (SnO 2 -RGO with bandgap of 3.88 eV), the bandgap energy of α-Fe 2 O 3 /SnO 2 -RGO hybrids (3.53 eV) was reduced by adding α-Fe 2 O 3; the narrower bandgap facilitated the sensing materials to release more electrons and form more oxygen ions at room temperature. Besides, the high carrier migration of RGO, which served as continuous phase, identical structure with ultrasmall particle size of α-Fe 2 O 3 and SnO 2 (about 3–6 nm), and abundant chemisorbed oxygen species on the surface (20.8%) of the sensing materials, as well as their suitable bandgap (3.53 eV) in the sensing materials, significantly improved NO 2 response at room temperature. Among the sensors fabricated, α-Fe 2 O 3 /SnO 2 -RGO-15-based NO 2 sensor had the highest response of 7.4 with a short response time of 59 s towards 1 ppm NO 2 ; it could even reach a response of 2.6 towards 100 ppb NO 2. Notably, α-Fe 2 O 3 /SnO 2 -RGO-15 sample has excellent capability to recognize NO 2 , where the response value (7.4) towards 1 ppm NO 2 is about 7 times higher than that of 100 ppm ammonia and common volatile organic compounds (formaldehyde, toluene, ethanol and acetone). Such NO 2 sensor has superior repeatability with negligible response deviation towards 1 ppm NO 2 for four reversible cycles. This makes it to have a great potential application in the field of NO 2 detection. [ABSTRACT FROM AUTHOR]

[Display omitted] The metal oxides-based chemiresitive gas sensors have attracted enormous interest because of their exellent sensing perforamcnes, which have emerged as very promising candidates for gas monitoring. However, from the view of organophosphorus compounds detection, a unique combination of low detection limit and fast respons/recovery rate remains challenging. Herein, the synersgitic effects of oxygen vacancy engineering and surface gold decoration enabling excellent sensing performances for detection of dimethyl methyl phosphonate (DMMP, a typical organophosphorus) is reported. To demonstrate the proof of concept, Au nanoparticles (NPs) decorated oxygen vacancy-enriched SnO 2 hybrids (designated as Au-O-SnO 2) were designed as sensing materials, where the O-SnO 2 samples were fabricated by introduction of oxygen vacancies onto commercial SnO 2 through organometallic chemistry-assisted approach using (CH 3) 2 SnCl 2 as precursor, followed by deposition of Au NPs by an in-situ reduction routine. After optimizing Au NPs content in hybrids (1 wt%, 3 wt%, 5 wt% and 7 wt%), O-SnO 2 decorated with 5 wt% Au NPs (designated as Au-O-SnO 2 -5) exhibits excellent DMMP sensing performances, such as, an enhanced recoverable response of 1.67 to 680 ppb DMMP, low detection limit of 4.8 ppb, short response time of 26 s and recovery time of 32 s, as well as good selectivity, which are much better than that of commercial SnO 2 (C-SnO 2) and O-SnO 2 , and Au NPs decorated C-SnO 2. Based on the detailed investigation, the enhanced DMMP sensing performances of Au-O-SnO 2 hybrids can be mainly ascribed to the synergistic effect of increasing surface active sites induced by oxygen vacancies, the chemical and electronic sensitization of Au NPs. As a result, Au-O-SnO 2 -5 hybrids display relatively low activation energy of 24.11 kJ/mol for DMMP oxidization, which is lower than that of O-SnO 2 (35.54 kJ/mol). Our results provide a feasible method for boosting sensing performances for DMMP detection, paving new way for fabrication of metal oxides-based gas sensors for rapid detection of trace organic compounds with complexed structures. [ABSTRACT FROM AUTHOR]

[Display omitted] Application of metal organic frameworks (MOFs) on sensors is of great interest for researchers. Film forming ability of the sensing material is very important for both the preparation process and sensing properties of the devices. Humidity sensors based on UIO-66 derived polyelectrolyte films were well prepared by in situ thiol-ene click cross-linking polymerization in this work. The hydrophilicity of the sensing film could be controlled by the feed ratios. The optimized humidity sensor shows a fast response to RHs change (Res/Rec time is 3.1 s/1.5 s, respectively) with ∼1.2% RH of humidity hysteresis. The water molecules adsorption behavior of the film and the sensing mechanism were also be investigated. The humidity sensor with good water and thermal stability and repeatability was applied in breath monitoring, which can well distinguish different breath states. [ABSTRACT FROM AUTHOR]

Owing to the outstanding dielectric properties derived from the conjugated π-electron systems, conjugated polymers have been explored and developed in capacitive humidity sensors for a few decades. In this work, a series of composites – mesoporous silica and semiconducting polymers – MCM-41 (MCM, Mesoporous Crystalline Material)/PEDOT (poly(3,4-ethylenedioxythiophene)) were chemically obtained by in-situ polymerization at 0 °C, while the amounts of PEDOT were adjusted by different evaporation times of EDOT (3,4-ethylenedioxythiophene) in the porous MCM-41 film. Additionally, it was able to modulate both the dielectricity and porosity of the composites via this convenient approach. The obtained capacitive humidity sensors based on MCM-41/PEDOT composites exhibit much better sensing performance than their bulk counterparts, with wider humidity sensing range, higher sensitivity and much faster response speed. [ABSTRACT FROM AUTHOR]

Graphic abstract In 2 O 3 and zeolitic imidazolate framework-8 (ZIF-8) heterostructures were firstly synthesized and designed as efficient sensing materials for ppb-level NO 2 detection. Abstract The development of NO 2 gas sensors is of great importance for air quality monitoring and human health. In this work, In 2 O 3 and zeolitic imidazolate framework-8 (ZIF-8) heterostructures were synthesized and designed as efficient sensing materials for NO 2 detection. The ZIF-8 nanocrystals were uniformly deposited on In 2 O 3 nanofibers (NFs) by using a self-template strategy, where In 2 O 3 /ZnO NFs act as the source of Zn2+ for the formation of ZIF-8 and as the template. By tuning the amount of Zn2+ in the composite NFs, different morphologies from In 2 O 3 NFs with minimal ZIF-8 loading to an In 2 O 3 /ZIF-8 core-shell complex were obtained. The optimized In 2 O 3 /ZIF-8 NFs show a remarkably high response to 1 ppm NO 2 (R g /R a = 16.4) and enhanced humidity resistance due to the hydrophobicity of ZIF-8 in comparison with those of the pristine In 2 O 3 NF sensor (R g /R a = 4.9) at 140 °C. The gas sensing mechanism of In 2 O 3 /ZIF-8, which is based on electron transduction, surface chemistry, and the functional interface between the loaded ZIF-8 and In 2 O 3 matrix, was proposed. Additionally, the large number of pores, which were formed by the in situ conversion of ZnO grains in the matrix, ensures that all parts of the In 2 O 3 NFs are accessible to gases. This facile strategy paves the way for the design of metal oxide/MOF complex architectures with tunable metal centers for various applications, including gas sensing. [ABSTRACT FROM AUTHOR]

In this paper, we demonstrate room-temperature NO 2 gas sensors using Pd nanoparticles (NPs) and SnO 2 NPs decorated reduced graphene oxide (Pd-SnO 2 -RGO) hybrids as sensing materials. It is found that ultrafine Pd NPs and SnO 2 NPs with particle sizes of 3–5 nm are attached to RGO nanosheets. Compared to SnO 2 -RGO hybrids, the sensor based on Pd-SnO 2 -RGO hybrids exhibited higher sensitivity at room temperature, where the response to 1 ppm NO 2 was 3.92 with the response time and recovery time being 13 s and 105 s. Moreover, such sensor exhibited excellent selectivity, and low detection limit (50 ppb). In addition to high transport capability of RGO as well as excellent NO 2 adsorption ability derived from ultrafine SnO 2 NPs and Pd NPs, the superior sensing performances of the hybrids were attributed to the synergetic effect of Pd NPs, SnO 2 NPs and RGO. Particularly, the excellent sensing performances were related to high conductivity and catalytic activity of Pd NPs. Finally, the sensing mechanism for NO 2 sensing and the reason for enhanced sensing performances by introduction of Pd NPs are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Nanoporous polymer monolith-supported Degussa P25 as adsorptive photocatalysts was successfully synthesized by a simple solvothermal polymerization of polymeric precursor in the presence of P25 fine powder. TiO2 nanoparticles distribute homogeneously in the matrix of nanoporous polymer monoliths. The monolithic morphologies benefit separation and recovery in practical applications. In addition, the composites reveal high BET surface area and large pore volume, thus exhibiting excellent adsorptive properties for organic compounds, which is propitious to enrichment and photodegradation of the organic target. The synthesis of adsorptive supports for immobilization of powdery photocatalysts would show significant improvements in both practical use and degradation efficiency of photocatalysis in environmental protection. [Copyright &y& Elsevier]