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[Display omitted] • H 2 O 2 generated from PMS is critical precursors of 1O 2. • Co sites in ZIF-L@Fe 28 denote all 1O 2 , SO 4 ·−, ⋅O 2 −, ·OH and H 2 O 2 generation. • Fe sites prefer 1O 2 and H 2 O 2 generation via PMS*→H 2 O 2 →1O 2 pathway. Verifying the role of H 2 O 2 is a critical challenge for deepening the understanding of the mechanism of peroxymonosulfate (PMS)-based advanced oxidation processes (AOPs). In this research, Co, Fe bimetallic organometallic frameworks (ZIF-L@Fe 28) were prepared, and their ultrahigh activities via H 2 O 2 generation at Fe and Co sites were experimentally and theoretically verified. The important contribution of H 2 O 2 to 1O 2 production was identified through the quantifications of the mutual transformation of active species. Co sites were identified as the most active positions for PMS activation because of they strongly triggered 1O 2 , SO 4 ·−, ⋅O 2 −, ·OH, and H 2 O 2. However, the self-quenching of active species suppressed the efficiency and selectivity of 1O 2 generation at Co sites. In contrast to Co sites, Fe sites had selective preference for H 2 O 2 generation, and the transformation of H 2 O 2 to 1O 2 further enhanced the performance of ZIF-L@Fe 28. The supplementary discussion from the perspective of H 2 O 2 will enable the further application of the PMS activation mechanism. [ABSTRACT FROM AUTHOR]

[Display omitted] • Co-MOF/GO activated PMS could remove BAC in a wide pH range of 3–11. • SO 4 − and OH were identified as critical precursors for 1O 2 generation rather than DO and O 2 –. • Co (II) and Co (III) act as dominant active sites for PMS attachment. Peroxymonosulfate (PMS)-triggered non-radical pathways have potential for environmental application due to the high activity and pH tolerance of singlet oxygen (1O 2). However, the mechanism of 1O 2 generation remains unclear. Herein, new insights into 1O 2 generation are discussed based on the postulated precursors of PMS, DO, O 2 –, SO 4 −, and OH with Co-MOF/GO catalyst. According to experimental results and theoretical calculation, Co (II) and Co (III) were identified as dominant active sites for PMS attachment, leading to the simultaneous breakage of S-O and O-O bonds and the generation of SO 4 −, OH, and 1O 2. SO 4 − and OH were critical precursors for 1O 2 generation, while PMS self-decomposition had a small contribution. DO and O 2 – acted more likely as quenchers than vital precursors of 1O 2. Results provide in-depth understanding of the mechanism of 1O 2 generation to broaden the application prospects of PMS oxidation technology. [ABSTRACT FROM AUTHOR]

• A potential non-fullerene acceptor used to fabricate NIR OPD with low dark current. • The wider applicability of the non-fullerene acceptor is also demonstrated. • The NIR OPD with extremely low dark current (7.04 × 10-10 A/cm2) at –1 V. • The OPD displayed a high value of D * in the NIR region and sub-microsecond response times. By tuning the band gaps of their active layer materials, organic photodetectors (OPDs) can display good responses in the near-infrared (NIR) region, making them useful for applications in biomedical imaging and optical communication. Nevertheless, NIR OPDs have tended to suffer from low specific detectivity (D*), due to a high dark current. In this study, we employed 3TT-FIC, a non-fullerene acceptor (NFA), to develop OPDs capable of operating with extremely low dark currents and high response speeds. After fine tuning the blend ratio of the donor (PM6) and acceptor (3TT-FIC), we obtained an OPD that operated at a low dark current (7.04 × 10-10 A/cm2) at –1 V with a high value of D* (2.6 × 1013 Jones) at the wavelength of 850 nm. We also describe the wider applicability of 3TT-FIC and its good potential for applications as an NFA in NIR OPDs. [ABSTRACT FROM AUTHOR]

• This paper reviews history and evolution of layered oxides. • The challenges and prospects are included. • This review paper also offers some guidance for further designing layer oxides. Rapid exploitation of renewable energy sources for replacing the conventional fossil fuels drives the development of electrical energy storage (EES) systems. Sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs) are considered as the promising low-cost candidates for the application in large-scale energy storage by virtue of the abundant reserves of sodium and potassium resources. In NIBs and KIBs, cathode plays a critical role in the electrochemical performances, and hence searching for appropriate cathode materials becomes the key point. Particularly, layered oxide cathodes with superior specific capacity and appropriate operating voltage are the most fascinating electrode materials for NIBs and KIBs. In light of performances, the fundamental and recent researches of layered oxide cathodes are reviewed for NIBs and KIBs. However, several major challenges including irreversible phase transition, low energy density, poor air stability, oxygen redox chemistry and inferior cycling stability need to be overcome. All in all, a comprehensive review for the layered oxide cathodes is present accompanied with solutions for these problems, especially mentioning the different functions of different elements and ionic potential (Ф) for guiding the design of layer oxides with exceptional performances. The challenges and prospects are also included with the hope of these materials applying in the next-generation energy storage devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • Ni and S atoms in Ni 3 (HTTP) 2 /GO had negligible contributions for catalysis directly. • Electron transfer via "GO-C-O-S-C-Ni 3 (HTTP) 2 " bridge was important for catalysis. • S atoms were more favorable for generating connection bridges than N and O atoms. Electron transfer capability as crucial properties of anode is directly related to electrocatalytic performance. However, the contributions of electron transfer were always under estimated due to the ambiguous mechanism of electrocatalysis. In this paper, a new electron transfer bridge was constructed in Ni 3 (HTTP) 2 /GO to provide a new insight into electrocatalytic performance enhancement. The contributions of active sites candidates, including metal sites, ligands (metal bridging atoms), and electron transfer bridges were innovatively separated. As replacement experimental results (of metal sites and metal bridging atoms), both metal sites and metal bridging atoms contributed slightly as the active center directly for the electrocatalytic degradation of tetracycline hydrochloride (TCH). The great improvement was attributed to the generation of "GO-C-O-S-C-Ni 3 (HTTP) 2 " bridges, in which S atoms from ligands were critical anchoring sites for the connection of two 2D layers (Ni 3 (HTTP) 2 and GO layer). The experimental and density functional theory results showed Ni 3 (HTTP) 2 could donate electrons to GO layers, leading the electrostatic imbalance of charge density to facilitate electron withdrawal from pollutions (not only TCH, but also dyes and complex microbial flora). The results of this paper provide a new strategy for improving electrocatalytic efficiency by adjusting electron transfer for novel practical applications of Ni 3 (HTTP) 2 /GO composites. [ABSTRACT FROM AUTHOR]

• Isolation of cellulose from wastes realized efficient utilization of resources. • For Congo red and Cu2+, the hydrogels had excellent adsorption efficiency. • The prepared hydrogels exhibited excellent reusability in adsorption. • The adsorption mechanisms of hydrogels on Congo red and Cu2+ were revealed. In order to obtain high-efficiency and sustainable adsorbents for both heavy metal ions and dyes, Millettia speciosa Champ cellulose and chitosan were used to prepare magnetic hydrogels with in-situ synthesis of Fe 3 O 4 in this study. The results of characterization by vibrating sample magnetometer (VSM), Fourier transform infrared reflection (FTIR), X-ray diffraction (XRD), thermogravimetry analysis (TG and DTG), scanning electron microscope (SEM), mercury intrusion porosimetryand (MIP) and texture analysis indicated the magnetic hydrogels with high strength, high porosity and macroporous structure were successfully prepared, and they could be recovered by magnetic field. Besides, the prepared hydrogels had excellent adsorption effect on Cu2+ and Congo red (CR). The adsorption process for Cu2+ conformed to pseudo-first-order kinetics model better, whereas that for CR conformed to pseudo-second-order kinetics model better. Adsorption isotherm analysis showed that Freundlich model could better describe the adsorption process for both CR and Cu2+. The thermodynamic study results proved that the adsorption process for CR or Cu2+ was spontaneous and endothermic. Besides, the increase of pH had a negative effect on CR adsorption and a positive effect on Cu2+ adsorption. Adsorption mechanisms analysis revealed that electrostatic attraction and hydrogen bonding were involved in the CR adsorption, and amino groups acted dominantly in the process of Cu2+adsorption. Furthermore, the prepared hydrogels exhibited excellent reusability, remaining their adsorption efficiency above 75% in five consecutive cycles. Therefore, the prepared hydrogels were expected to be promising materials for both heavy metal ions and dyes removal from waste water. [ABSTRACT FROM AUTHOR]

[Display omitted] • A bamboo fiber/graphene oxide (M−CBF−rGO) aerogel with a sponge-like porous structure was fabricated. • The M−CBF−rGO shows excellent superelasticity and mechanical durability (7,000 cycles). • The derived sensor exhibits superior operating range (0–300 kPa) and strain sensitivity (892.9). • The sensor can be capable of detecting human physiological signals and monitoring human activity. Superelastic, breathable, and flexible piezoresistive sensors with excellent sensing performance are drawing tremendous attention in wearable electronics and sleeping furnishings. However, simultaneous realization of their high performance is still a huge challenge. In this study, inspired by the pore structure of natural sponges, a high-performance sponge-like bamboo fiber/graphene oxide aerogel piezoresistive sensor (M−CBF−rGO) was prepared utilizing bamboo fibers (BFs) and graphene oxide (GO) as raw materials through freeze casting and carbonization. Benefiting from the unique porous structure with effective absorbing/releasing energy, the M−CBF−rGO aerogel sensor exhibits excellent superelasticity (not being destroyed under 90 % deformation), mechanical durability (7,000 cycles), and good breathability. Moreover, the M−CBF−rGO sensor demonstrates ultra-high strain sensitivity (892.9), a wide detection range (0–300 kPa), and a fast recovery time (20 ms). Taking advantage of these benefits, the M−CBF−rGO sensor can not only be applied to detect human signals ranging from finger motion to swallowing recognition, but also integrated into the cushioning materials of upholstered furniture to generate a sensing array for monitoring and recogniting human activity including sitting postures and sleeping positions in real-time. This sensor demonstrates the potential application prospects in the fields of human health diagnosis, smart wearable products, and intelligent upholstered furniture. [ABSTRACT FROM AUTHOR]

• An effective activator of persulfate was obtained based on natural clinoptilolite. • Modified zeolite + heat synergistic activation can achieve rapid degradation. • The synergistic mechanism of degradation based on radicals has been revealed. • The activator showed good performance in three consecutive cycles. An easily obtainable and cheap activator was obtained with natural clinoptilolite, which was easy to be modified with a ferrous sulfate solution. The modification can greatly improve the Fe/C ratio of the zeolite surface without changing the typical porous structure of natural clinoptilolite. The modified zeolite can activate sodium persulfate to degrade 2-methoxyphenol (MOP, a typical organic contaminant in salty wastewater), and has a heterogeneous-homogeneous synergistic effect accompanying heat. The mechanism investigation shows the activation of single modified zeolite is more complex at normal temperature (25 °C), and many types of free radicals are involved in the degradation through multiple pathways. Rapid degradation of MOP can be achieved with the synergistic effect of the modified clinoptilolite + heat, and the degradation ratio reaches 95.0% in 10 min caused by the generation of more sulfate- and superoxide radicals. Comparing with the effect of the directly activated persulfate process by ferrous sulfate, a better degradation effect could be obtained with active substance slowly released by the modified zeolite. And adding thermal activation can further increase the activation rate and utilization of oxidants. Finally, better mineralization efficiency achieves, and the total organic carbon (TOC) removal ratio with synergistic activation is about 5 times that of a single activation by modified zeolite within 20 min. In addition, the activator shows good activated performance in three consecutive cycles. The MOP degradation ratio using M80-zeolite, reducing by 21.8% at 10 min in the third use, could be recovered to 95.0% with the original modified method. [ABSTRACT FROM AUTHOR]

• A novel MOFs/PEI/TMA composite membrane is developed for heavy metal removal. • NH 2 -MIL-125(Ti) provided preferential water channels to improve permeability. • New and facile cross-linking process provides strong positive charge surface. • The interaction between NH 2 and PEI/TMA system increases the stability of MOFs. • Nanocomposite membrane has 369% higher flux than the pristine membrane. In this study, a novel positively charged nanofiltration (NF) membrane was fabricated by incorporating metal–organic frameworks (MOFs) into polyethyleneimine (PEI) and trimesic acid (TMA) cross-linking system. NH 2 -MIL-125(Ti) provides preferential water channels to improve the permeability of the composite membrane. The effects of NH 2 -MIL-125(Ti) loading on the membrane morphology, structure and properties were investigated by ATR-FTIR, SEM, EDS, AFM, Zeta potential measurements, etc. Studies have shown that the optimal preparation condition was determined at 0.010 wt% NH 2 -MIL-125(Ti) loading. The prepared membrane exhibited a high permeability of 12.2 L·m−2·h−1·bar−1 and a NiCl 2 rejection of 90.9%. Compared with the pristine composite membrane, the membrane with appropriate amount of NH 2 -MIL-125(Ti) greatly improved the permeability (369.2%). The combination of NH 2 -MIL-125(Ti) and PEI/TMA cross-linking system has positive significance for the heavy metal wastewater treatment industry. [ABSTRACT FROM AUTHOR]

• 2-Methoxyphenol can be efficiently degraded by thermal or alkali activated Na 2 S 2 O 8. • Rapid degradation can be achieved by thermal-alkali synergistic activation. • Degradation intensification mechanism based on radicals has been revealed. Both thermal and alkali are effective means of persulfate (PS) activation, and the synergistic effect of them should achieve a great degradation result. It is evaluated for treating coal chemistry industry wastewater because the by-product produced in the process is sulfate, which is pre-existing in the wastewater. With thermal and alkali synergistic activation, the application of the response surface method revealed the effects of temperature, pH and concentration of persulfate on the degradation ratio of 2-methoxyphenol (MOP, a typical contaminant in coal chemical industry wastewater) and their interactions. The results showed that the degradation rate of the contaminant was temperature and pH dependent, while chloride (Cl−) and sulfate (SO 4 2−) ions had no obvious negative effect. The degradation ratio could be enhanced with higher activation temperature and pH (7–12). The faster degradation could be achieved by thermal-alkali synergistic activation, and the degradation ratio of 88.4% and 93.8% could be achieved at pH = 12 within 10 min and 20 min, respectively. Electron spin resonance (ESR) spectra and free radical scavenging experiments indicated that MOP degradation was achieved by the oxidation of both sulfate radical (SO 4 −) and hydroxyl radical (OH) at pH = 6, and only by OH at pH = 12. In addition, the radical reaction was intense under thermal-alkali synergistic activation of PS, while the quenching reaction was ineffective. [ABSTRACT FROM AUTHOR]

• Hollow spherical PDA-Mo precursors assembled by polymerization of dopamine hydrochloride with Mo 7 O 24 6-. • In-situ pyrolysis method makes the MoO X active sites highly dispersed. • Oxidation of catalyst enlarge meso-/micro-pores, specific surface area and oxygen vacancies. • MoO X /C catalyst exhibits high ODS performance under mild condition. To obtain low-sulfur fuel and reduce SO X emissions, we are developing a MoO X /C hollow sphere catalyst with adjustable oxygen vacancies for oxidative desulfurization (ODS) of fuel. Herein, porous MoO X /C hollow spheres with nanosheet structure were synthesized by pyrolysis of polydopamine-molybdic (PDA-Mo) precursors. The limiting effect of the carbon layer caused MoO X to be uniformly embedded in the carbon support. Then partial oxidization led to forming more meso-/micro-pores and a larger specific surface area (406.4 m2 g−1), and to obtain crystal and abundant oxygen vacancies, thus increasing the content of effective active sites and enhanced the activity of the composite catalyst. Accordingly, the MoO X /C catalysts were employed in oxidative desulfurization (ODS) with H 2 O 2 as an oxidant and displayed excellent performance. The dibenzothiophene (DBT) was eliminated 100% on the optimal catalyst MoO X /C-750–4 within 15 min at 60 ℃ and had a high turnover frequency (22.6 h−1). Furthermore, in-situ formation of C encompassing MoO X could reduce active site leaching and maintain good reaction stability. After eight recycles, the removal rate of DBT was still 98.6%. This study provides a universal in-situ pyrolysis strategy for constructing supported metal oxides and designing high-capacity ODS catalysts. [ABSTRACT FROM AUTHOR]

• LiCrTiO 4 nanoparticles with carbon layer (LCTOC) are successfully prepared by sol–gel method. • Reversible capacity of 114.3 mAh/g is achieved at 1 A/g over 2500 cycles, indicating its ultrastable cycling stability. • Morphology and structure of LCTOC are maintained perfectly during long-term cycling. • Such a superior capacity of LCTOC is attributed to the improved conductivity and ion-diffusion rate. Hybrid magnesium-lithium ion batteries (HMLBs) merge Li+ faster kinetics with dentrite-free and low-cost Mg anode and are arousing widespread concern. It is regrettable that its development is limited by the lack of advanced electrode materials. Herein, LiCrTiO 4 nanoparticles with/without carbon layer (LCTOC/LCTON) are successfully prepared by sol–gel method and used as cathodes for HMLBs. Compared with LCTON, LCTOC not only exhibits a high reversible capacity (139.3 mAh/g at 100 mA/g after 100 cycles), but also possesses an excellent rate performance (123.1 mAh/g at 500 mA/g). Notably, a reversible capacity of 114.3 mAh/g at 1 A/g has been achieved over 2500 cycles, indicating an ultrastable cycling stability. The enhanced electrochemical performance of LCTOC is attributed to the improved conductivity and ion diffusion rate, and decreased polarization value induced by the carbon coating layer with a higher surface area. In addition, the ion storage mechanism of LCTOC is explored by ex-situ tests. The morphology and structure of LCTOC have been maintained perfectly during the long-term charge–discharge process, indicating a highly structural stability and reversibility. This study exhibits a promising application of LCTOC in the fabrication of advanced HMLBs. [ABSTRACT FROM AUTHOR]

[Display omitted] • Amphiphilic nanoreactor based on natural halloysite nanotube with enclosing MoO x. • Amphiphilic reacting nano-system and highly dispersed active center exhibiting prominent performance. • Confinement effect showing excellent stability. • Oxidation products removing simultaneously by hydrophilic lumen adsorbing. • Simply synthesis, simplified and green process. Hollow nanomaterials are regarded as the outstanding supports due to their confinement effect and stable carries, which can enhance the performance of the supported catalysts and even simplify the process. In this work, halloysite nanotubes (HNT) are chosen as the support due to their monoclinic tubular structures with two different surface compositions and charges. By a simple impregnation-calcination approach, MoO x is immobilized in the internal surface of HNT, then modify with organosilanes on the external surface of HNT to yield the amphiphilic Mo/HNT/S nanoreactor. The catalyst exhibits prominent activity for oxidative desulfurization in solvent-free system, the desulfurization rate of dibenzothiophene (DBT) reaches 100 % and the turnover frequency (TOF) value reaches 67.5 h−1 at 60 °C with 15 min, which is higher than most reported Mo-based catalysts. The hydrophobic surface enables the nanoreactor to be well dispersed in oil phase, and H 2 O 2 solution in the hydrophilic cavity can extract DBT to form a concentrated microenvironment of the reactants and reactive oxygen species. The confinement function of the HNT nanoreactor can enhance the activity and stability of active ingredients (MoO x) over at least 5 cycles. Additionally, oxidation products can be retained in the hydrophilic lumen and completely separated from the model fuel. This amphiphilic catalytic system eliminates the following solvent extraction step in the ODS procedure. Thus, the catalyst is a promising candidate for large-scale industrial application. [ABSTRACT FROM AUTHOR]

Herein a bioactive component of mannose-rich oligosaccharides with potent anti-inflammatory capacity was employed to functionalize SeNPs to achieve high stability, biocompatibility and therapeutic potential by promoting macrophages reprogramming leading to inflammation resolution. This study not only provides strategy for functionalization of nanomedicines using structure-optimized MRO, but also reveals the action mechanism on successful treatment of IBD and other intestinal diseases. [Display omitted] • Bioactive mannose-rich oligosaccharides were produced by enzymatic hydrolysis. • Functionalized MRO-SeNPs reprograms macrophage towards M2 polarization. • MRO-SeNPs effectively alleviates DSS-induced colitis in mice. Inflammatory bowel disease (IBD) is a global disease and usually classified into Crohn's disease (CD) and ulcerative colitis (UC), in which the inflammatory response is known to play a pivotal role. Herein, a bioactive component of mannose-rich oligosaccharides (MRO) was produced by enzymatic hydrolysis with most potent anti-inflammation and employed to functionalize selenium nanoparticles (SeNPs), aming to solve of inflammation in UC by accelerating the reprogramming of macrophages. In this study, SeNPs was prepared by selenite and MRO with ascorbic acid reduction. The stability and biocompatibility of SeNPs was obviously improved by the functionalization of MRO, resulting in spheres (2 µM Se) carrying around 26 ng/ml MRO (MRO-SeNPs) with an average diameter of 70 nm remained stable in 60 d. In addition, efficient cellular uptake of MRO-SeNPs in macrophages was detected by contribution of MRO targeted to the receptors of macrophages. As expected, MRO-SeNPs exhibited improvement of macrophage reprogramming in vitro , thus leading to a typical M2 polarization profile of cytokine expression. Furthermore, in DSS-induced mouse colitis model, MRO-SeNPs effectively mitigated colitis by suppressing the pro-inflammatory such as IL-1β, IL-6, TNF-α, IL-12 and MCP-1 cytokines in situ , and exerted salient antioxidant capacity in colon tissues. As a result, MRO-SeNPs exhibited therapeutic potential by promoting macrophages reprogramming leading to inflammation resolution. Taken together, this study not only provides strategy for functionalization of nanomedicines using structure-optimized MRO, but also reveals the action mechanism on successful treatment of IBD and other intestinal diseases. [ABSTRACT FROM AUTHOR]

• Expanded graphite (EG) was applied as the support of CuFe 2 O 4. • Composite catalyst (EG-CuFe 2 O 4 -U) was synthesized by the urea-assisted hydrothermal method. • EG-CuFe 2 O 4 -U possessed outstanding catalytic performance to PDS activation for TC degradation. • Both SO 4 ·−, ·OH and 1O 2 were generated in the EG-CuFe 2 O 4 -U/PDS system. • The intermediates of TC were detected and analyzed. Owing to the stable crystal structure and wide range of pH applications, CuFe 2 O 4 particles have been intensively concerned in the field of advanced oxidation, but their serious agglomeration and slow catalytic efficiency are still the stumbling blocks. The composite catalyst (EG-CuFe 2 O 4 -U) prepared by urea-assisted hydrothermal method with expanded graphite (EG) as the substrate immobilized CuFe 2 O 4 not only exposed more active sites but also exhibited a higher electron transfer rate. Additionally, EG-CuFe 2 O 4 -U showed excellent performance in degrading tetracycline (TC) in model wastewater by activated peroxydisulfate (PDS). The synthesis mechanism of EG-CuFe 2 O 4 -U and the principle of urea in the formation of reduction environment were discussed in detail by the experimental results of key preparation parameters and characterization. Meanwhile, several critical influencing factors were examined including PDS concentration, catalyst dosage, initial pH of the solution, and the change of pH in different systems. Furthermore, the removal efficiency and mineralization efficiency of TC (50 ppm) exceed 91% and 34.6%, on the conditions of 0.4 gL−1 EG-CuFe 2 O 4 -U, 6 mM PDS, initial solution pH of 4, and room temperature. What's more, the internal reaction mechanism of free radicals and non-free radicals in the EG-CuFe 2 O 4 -U/PDS system was further elaborated via scavenging tests, electron paramagnetic resonance (EPR). Finally, based on twenty-one principal intermediates of TC, four possible degradation pathways were proposed. In general, the catalyst with a rich pore structure and high catalytic activity has great potential in the effective activation of PDS and is prospective to be further applied in the field of antibiotic wastewater degradation. [ABSTRACT FROM AUTHOR]