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Plasmonic heterojunctions present excellent photocatalytic performance for water splitting. Herein, a novel S-scheme heterojunction of CdS-ZnO nanorods assisted with low-content Au (<1 wt%) plasmon was achieved successfully, which possessed the H 2 -generated efficiency of 14.36 mM h−1 g−1. Remarkable catalytic activity stems from the S-scheme mechanism, metal plasma resonance and the unique flower-shaped morphology. S-scheme endues the heterojunction with efficient carrier separation and strong redox capacity, and surface plasmon resonance (SPR) generated from low-content Au broadens light absorption range and injects hot electrons into the heterojunction. In-situ XPS measurements verified an S-scheme carrier migration mechanism as well as hot electrons transfer. Other optical and photoelectric characterizations, as well as simulation calculation by finite difference time domain (FDTD) were also utilized to conjecture the probable mechanism. Low content noble metal and unique morphology accelerate the photocatalytic H 2 -production, and it likely proposes the promising strategy for practical application of photocatalysis for solar energy conversion. [Display omitted] • Three-dimensional flower-like structure is composed of nanorods. • Heterostructure presented an efficient H 2 -production rate of 14.36 mM h−1 g−1. • SPR of low-content Au accelerated photocatalytic hydrogen production. • In-situ XPS verified S-scheme carrier migration and SPR hot electrons transfer. • S-scheme endued heterojunction with an excellent redox capacity. [ABSTRACT FROM AUTHOR]

A series of supported MnOx/MgAl-layered double hydroxide (LDH) catalysts were prepared by hydrothermal co-precipitation to investigate their catalytic performances for low-temperature formaldehyde oxidation reactions. Activity tests show that the 10Mn/Mg3Al1-LDH catalyst exhibits higher efficiency for low-temperature formaldehyde oxidation with a high CO2 yield. It also shows remarkable long-term operational stability as well as good adaptability to different velocities and humidities. Various characterizations were carried out to establish the possible structure–activity correlations. The results show that there were a large number of hydroxyl groups in the 10Mn/MgAl-LDH catalysts, and the hydroxyl groups were positively correlated with Mg2+ content. The outstanding catalytic performance of 10Mn/Mg3Al1-LDH can be attributed to abundant surface hydroxyl groups, surface adsorbed oxygen and higher Mn4+/Mn3+ ratios. Through in situ Fourier-transform infrared spectroscopy (in situ FTIR), it was revealed that formaldehyde was gradually converted into CO2 and water with dioxymethylene (DOM), formate and carbonate as the major intermediates under the action of both active oxygen and active hydroxyl groups. The active oxygen and active hydroxyl groups consumed in the process are continuously replenished by the effective reaction between the oxygen molecules in the air and the active site of the catalyst. The low-temperature asynchronous conversion of formaldehyde results in the accumulation of some intermediates on the catalyst surface covering the active center, which induces catalyst deactivation. [ABSTRACT FROM AUTHOR]

• ZnAlCe catalysts were prepared to catalyze the direct synthesis of GC. • The involvement of CeO2 enhanced the formation of the frustrated Lewis pairs. • Zn4AlCe catalyst presented the highest GC yield of 28.9 %. • Possible formation pathway of GC from CO2 and glycerol was proposed. Zinc-aluminum-cerium composite oxide (ZnAlCe) catalysts were prepared by co-precipitation to catalyze the direct synthesis of glycerol carbonate (GC) from carbon dioxide (CO 2) and glycerol. The characterization results showed that the lattice oxygen served as Lewis basic centers and Ce4+ served as Lewis acidic centers on Zn 4 AlCe catalyst, and frustrated Lewis pairs (FLPs) were formed due to the steric hindrance in the catalyst structure. CO 2 was easily activated by FLPs because the acidic and basic centers of FLPs bound to the oxygen and carbon atoms of CO 2 , respectively. The experimental results indicated that Zn 4 AlCe catalyst presented excellent catalytic performance with good thermal stability and strong regeneration ability. Under the reaction conditions of 0.115 g catalyst, 12 h, 170 °C, 4.5 MPaCO 2 and 5 mL acetonitrile dosage, the GC yield and selectivity were 28.9 % and 51.0 %, respectively. The GC yield is relatively high among similar catalysts reported so far, which lays the foundation for future industrial considerations. [Display omitted] [ABSTRACT FROM AUTHOR]

• Multi-layer core-shell structure was fabricated without any template. • Ag was modified in situ by photochemical deposition to improve stability. • S-scheme and SPR effect endued heterojunction with an excellent redox capacity. • Reactive species trapping was conducted to ensure the dominant species. • Introducing oxygen during catalytic process can augment degradation efficiency. Constructing an efficient photocatalyst to accelerate charge separation with strong redox capacity is in pursuit all the way. Herein, a novel heterojunction was achieved for efficient organic degradation, which took advantages of S-scheme mechanism, metal surface plasma resonance (SPR) and unique morphology. The multi-layer core-shell structure can be regulated by aging time with template-free, and Ag nanoparticles were modified on the heterojunction by photochemical deposition in situ to facilitate electron transport and improve stability. S-scheme and SPR endues the heterojunction with broad light absorption, increased light utilization, efficient carrier separation, and strong redox capacity. An examination of reactive dynamics revealed that superoxide radicals and hydroxyl radicals are crucial for oxidative degradation. Introducing oxygen during the reaction process has been found to enhance the efficiency by 7 %. This article furnishes novel insights into a coordination of energy band engineering, structure regulation, as well as reaction process adjustment for facilitating photo-degradation reactions. [Display omitted] [ABSTRACT FROM AUTHOR]

Solid frustrated-Lewis-pair catalysts, based on Zn-Al composite oxide modified loaded with Au (Au x /ZnAl-CHT), were prepared by calcination of hydrotalcite precursors and tested for the direct synthesis of glycerol carbonate using CO 2 as the carbon source. An Au 5 /ZnAl-CHT catalyst shows the highest catalytic performance with the glycerol carbonate yield of 19.5 % and the selectivity of 50.5 % at 170 °C and 4.0 MPa CO 2 , while maintaining good thermal stability and excellent regeneration ability. A series of characterization results and density functional theory (DFT) calculations indicated the introduction of Au leads to more frustrated-Lewis-pairs in Zn-Al composite oxide (ZnAl-CHT), which improve the adsorption and activation of CO 2. Meanwhile, FTIR analysis indicates that glycerol is activated by Zn2+ for the formation of zinc glycerolate intermediates. The above dual synergistic activation processes effectively enhance the catalytic performance. And the reaction pathway is proposed for the synthesis of glycerol carbonate from CO 2 and glycerol. [Display omitted] ● Au 5 /ZnAl-CHT exhibited excellent catalytic performance with the yield of 19.5 %. ● Au played a potential "bridge" promoting the formation of FLPs. ● Characterization results and DFT calculations indicated that Au led to more FLPs. ● The reaction mechanism for direct synthesis of glycerol carbonate was proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Porous ZnO-CdS/Pt spherical-shell was fabricated without any template. • Heterostructure presented an efficient H 2 -production rate of 32.15 mM·h−1·g−1. • The exceptional structure improved light trapping and adsorption capacity. • S-scheme endued heterojunction with an excellent redox capacity. • The photo-generated electrons would be transferred rapidly from CdS to Pt. S-scheme heterojunctions present excellent photocatalytic performance for water splitting. Herein, an ideal distinctive heterostructure of porous ZnO-CdS/Pt spherical-shell was achieved by template-free method. It possesses the H 2 -generated efficiency of 32.15 mM·h−1·g−1, significantly surpassing the single or binary compounds. The remarkable photocatalytic activity stems from the unique morphology, S-scheme mechanism and the coordination of noble metal. Exceptional porous spherical-shell structure can localize the light, promote light scattering, increase adsorption capacity and bring abundant active sites. The reduction in transfer distance for carriers, inhibition of electron-hole recombination, as well as diminution of mobility resistance endues the heterojunction with efficient carrier separation and strong redox capacity. The probable mechanism was also estimated by the characterizations of XPS, UV, PL, PEC, EIS, M-S and ESR. This article provides a new method for spherical-shell structure fabricated without template, and proposes a significant promise for the construction and application of highly efficient photocatalysts for H 2 -production. [ABSTRACT FROM AUTHOR]

A new probe RB-CR for the detection of Cr3+ was constructed based on the conjugation between rhodamine B and phenylthiourea. The Cr3+ could trigger opening of the rhodamine spirolactam of RB-CR upon complexation selectively, sensitively and rapidly, resulting in a pronounced enhancement of absorption and fluorescence signal. Further fluorescence imaging study has suggested that RB-CR could be applied as a probe for Cr3+ surveillance in living HepG2 cells with low cytotoxicity, which provide us the feasibility of exploring the Cr3+ recognition process by the turn-on fluorescence response. Unlabelled Image • The probe exhibits highly rapid, selective and sensitive response to Cr3+ via coordination. • The probe is used to image Cr3+ in HepG2 cells, which suggests its excellent sensor ability in biological system. • This work would provide new inspiration for devising new way for cation chemosensors based on selective chelating. [ABSTRACT FROM AUTHOR]

A red fluorescent probe (Mito-V) with a long lifetime was designed to monitor viscosity changes with high selectivity and sensitivity. The fluorescence intensity and lifetime of Mito-V displayed a good relationship with the viscosity value, and Mito-V was successfully applied to sensing mitochondrial viscosity changes in living cells under different biological processes. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • A new off-on probe with accurate endoplasmic reticulum-targeting ability is developed for H 2 S 2 assay. • A sensing mechanism of greater nucleophilicity and reducibility by H 2 S 2 was proposed. • The probe exhibits highly selective and sensitive response to a specific hydrogen polysulfide H 2 S 2. • The indicates the fluctuations under the stimulation of inflammatory mediator and corticosteroid medication. Abstract Reactive sulfur species (RSS) play important physiological and pathological roles in biological redox homeostasis, cell signaling and the regulation of metabolism. Recent studies indicate that hydrogen polysulfides (H 2 S n) are the actual signal molecules in animal cells. Although H 2 S n have been implied to be answered for transcription factors, ion channels, and mediating tumor suppressors, more of their biological effects such as the effect of a specific hydrogen polysulfide in subcellular organelle are still needed to be elaborated. The detection of a specific hydrogen polysulfide (e.g. H 2 S 2) in living systems is essential for investigating their functions but is quite challenging. Herein, we report an off-on fluorescent probe ER-H 2 S 2 with a favorable photophysical property, high specificity, wide linear range and low cytotoxicity via a facile synthesis for the detection of H 2 S 2 endoplasmic reticulum-selectively in living cells and in zebrafish models in vivo, giving an example of the use of fluorescent probes in real-time imaging exogenous and endogenous H 2 S 2 in subcellular organelle during the course of inflammation and anti-inflammation. [ABSTRACT FROM AUTHOR]

• Mn 8 Ni 2 Ce a O x (a = 0–1.5) catalysts synthesized via co-precipitation strategy. • Mn 8 Ni 2 CeO x showed excellent catalytic activity and water resistance for toluene. • Ce doping accelerated the oxidation of benzyl alcohol/benzoate intermediates. • Ce doping could inhibit H 2 O adsorption on the catalyst surface. A series of metal oxides Mn 8 Ni 2 Ce a O x (a = 0–1.5) catalysts were prepared by hydrothermal co-precipitation to investigate the effect of Ce doping on manganese-based oxides for toluene catalytic combustion reaction. Activity evaluations show that Mn 8 Ni 2 CeO x (a = 1) catalyst exhibits highly efficient toluene oxidation activity and high yield to CO 2 production. Durability tests reveal that it has remarkably superior water resistance ability and promising potential for practical application. Various characterizations were conducted to explore possible structure-activity correlations. Results show that Ce introduction could construct the strong Ce-Mn interactions, generate more oxygen vacancies, facilitate lattice oxygen mobility, and increase the content of surface active oxygen. These changes efficiently utilize active oxygen species and accelerate the deep oxidation of benzyl alcohol/benzoate intermediates, therefore render activity advantages. Otherwise, Ce doping can effectively maintain the catalyst's structural stability while simultaneously inhibiting H 2 O adsorption on the catalyst surface under humid atmosphere, thus being conducive to the outstanding durability and water resistance ability. Mn8Ni2CeaOx (a = 0–1.5) synthesized via hydrothermal co-precipitation strategy exhibits highly efficient catalytic activity as well as superior water resistance. [Display omitted] [ABSTRACT FROM AUTHOR]

• ZnO/CdS clustered nanotube on the FTO is synthesized by hydrothermal methods. • Hydrogen evolution rate of ZnO/CdS is 7669 μmol g-1h−1 with the AQE of 55.25 %. • S-scheme mechanism enhances the high separation efficiency of carriers. • The recovery rate of ZnO/CdS on FTO substrates is over 99% after 2 circles. Herein, a cluster-like ZnO/CdS nanotube heterojunction photocatalyst was prepared on an FTO conductive glass substrate by a two-step hydrothermal method. The photocatalytic performance and electron transfer mechanism of ZnO and ZnO/CdS composite structures were analyzed through comparing the hydrogen production efficiency of ZnO and ZnO/CdS. The photocatalytic hydrogen production activity of ZnO/CdS (molar ratio 1:1) achieved 7669 μmol/g/h with the AQE of 55.25 %. Unique clustered tubular structure, wider light absorption range and higher carrier transfer rate endowed the composite with marvellous photocatalytic hydrogen production activity. In addition, the measurement of hydroxyl radicals and ESR verified that the electron transfer mechanism followed the S-scheme, which improved the separation efficiency of electron-hole pairs. The residual ratio of catalysts on the FTO substrate remained above 99 % after two cycles, which was remarkably higher than that of the powder catalyst (63 %). This work provides terrific potential for high-efficient, low-cost and recyclable photocatalysts of hydrogen production in the future. [ABSTRACT FROM AUTHOR]

The catalytic advantages of CeO 2 -MnO x catalysts for CB deep oxidation can be attributed to both the unique morphology effect and the Ce-Mn strong interaction in the nano rod shaped. [Display omitted] • CeO 2 -MnO x nano rods with different Ce/Mn molar ratios were synthesized. • Microstructure of CeO 2 -MnO x was analyzed by XRD Rietveld refinement. • CeO 2 -MnO x nano rod exposing defective {1 0 0} facet generates more oxygen vacancies. • Tunnel-like structured todorokite/vernadite phase favors lattice oxygen migration. • Increasing Mn content enriched surface Mn4+ and promoted Ce-Mn redox cycles. Series of nano rod shaped CeO 2 -MnO x catalysts with different Ce/Mn molar ratios were synthesized through facile hydro-thermal method and subjected to chlorobenzene (CB) complete catalytic oxidation tests. Detailed structural/chemical characterizations such as TEM/HRTEM, Rietveld XRD, N 2 adsorption/desorption, UV-Raman and H 2 -TPR were conducted. Results show that the designed nano rod shaped CeO 2 -MnO x binary oxides can be promising with highly efficient catalytic performance towards the complete oxidation of CB. The Ce/Mn-1/8 catalyst (Ce/Mn molar ratio 1:8) is verified as the most outstanding candidate among all the CeO 2 -MnO x catalysts obtained, which not only presents best catalytic activity but also gives less production of hazardous polychlorinated byproducts, along with excellent durability. Further characterizations reveal that such catalytic advantages can be attributed to both the unique morphology effect and the Ce-Mn strong interaction in the nano rod shaped CeO 2 -MnO x catalysts. The designed nano rod shaped CeO 2 -MnO x catalyst mainly exposes the more defective {1 0 0} facet, generating lattice micro-strain and favorable for forming more oxygen vacancies. While the formation of todorokite/vernadite phase with special tunnel-like structure which promoting the migration of lattice oxygen to catalyst surface. Moreover, the strong interaction between CeO 2 and MnO x can promote the (Ce4+/Ce3+ ↔ Mn4+/Mn3+) redox cycles and is beneficial for CB deep oxidation. Increasing Mn content leads to higher content of todorokite/vernadite phases, surface Mn4+ enrichment and shorter nano rods with more exposes lattice defects, thus rendering enhanced Ce-Mn strong interaction and morphology effect in Ce/Mn-1/8 catalyst. [ABSTRACT FROM AUTHOR]

Minute fluctuation in the intracellular pH is usually related to common diseases. The construction of fluorescent probes with wide response range, high selectivity, excellent sensitivity and good reversibility for intracellular pH detection is of great significance. In this work, we developed a novel pH probe (ZJ) based on a 3-hydroxy naphthalimide derivative via the optimization of substitute groups. ZJ showed a satisfying fluorescence performance to pH changes. ZJ manifests a remarkable fluorescence enhancement at 468 nm (over 12-fold) from pH 2.5 to 10.0. Live cell imaging data uncovered that ZJ can be successfully used in monitoring intracellular pH changes led by chloroquine, inflammation and autophagy, and confirmed with flow cytometry analysis. All these features render ZJ a potential candidate to study pH-associated drug development and physiological and pathological processes. A novel off-on probe based on the 3-hydroxy naphthalimide is developed for imaging intracellular pH changes caused by chloroquine, inflammation and starvation, which would be helpful in the analysis of related drug development and disease. Image 1 • A new fluorescent off-on probe is developed for pH assay via the optimization of substitute groups. • The probe exhibits wide response range, high selectivity, excellent sensitivity and good reversibility for pH. • The probe is used to image intracellular pH changes led by chloroquine, inflammation and autophagy. [ABSTRACT FROM AUTHOR]