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An aromatic moiety-free strategy is proposed for the effective excited state manipulation of the neutral luminescent manganese(II) halide. Interestingly, compared to the traditional monodentate ligand-based manganese(II) complexes, a dramatic enhancement of photoluminescent quantum yield of 0.413 is achieved by incorporating tri(pyrrolidin-1-yl)phosphine oxide (TPPO) as a new ligand without any aromatic moiety into the manganese(II) complex. The designed aromatic moiety-free neutral luminescent manganese(II) bromide (TPPOMnBr2) featuring an intense green emission (512 nm) and a short emission lifetime (0.564 ms) is employed to realize efficient X-ray imaging with a high spatial resolution value of 11.3 lp mm−1 and a low detection limit of 34.95 nGy s−1, making it a promising candidate for high-performance X-ray detection in the future. [ABSTRACT FROM AUTHOR]

Metal oxides can produce photo-induced oxygen vacancies under ultraviolet irradiation, where the oxygen vacancies can help produce hydrogen during the process of thermocatalytic decomposition of water. Therefore, a water splitting cycle on metal oxides, with consecutive photochemical and thermochemical reaction stages, can be established. In this study, cerium oxide (CeO2) was proved to have the ability of generating photo-induced oxygen vacancies after irradiation, and thereafter the water splitting reaction was performed at the photo-induced oxygen vacancies. The formation and consumption of photo-induced oxygen vacancies on CeO2 during the cycling process were detected by X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR). A hydrogen yield of 9.45 μmol g−1 h−1 for pure CeO2 was achieved. To improve the reactions in the photochemical stage, various transition and lanthanide metal ion doped CeO2 samples were prepared by the sol–gel method. Cu doped CeO2 showed the best hydrogen yield of 18.36 μmol g−1 h−1, which is 2 times that of pure CeO2. The testing results from XPS, Raman, photoluminescence (PL), and EPR indicated that metal ion doping improved light absorption performance and thus effectively promoted the generation of surface oxygen vacancies. Further DFT calculations highlighted that metal ion doping significantly reduced the formation energy of surface oxygen vacancies, and the improved H2 yield from various metal doped CeO2 showed an obviously negative correlation with the formation energy of surface oxygen vacancies. This indicated that oxygen vacancies had a dominant role in affecting the efficiency of hydrogen production. However, the metal doping inhibited the thermal reaction to some extent. Accordingly, the calculated energy barrier in the thermochemical stage appeared to be another factor affecting the H2 yield. [ABSTRACT FROM AUTHOR]

Organic–inorganic hybrid manganese halides with low cost, facile synthesis, and high-efficient luminescence have emerged as the novel candidate materials for X-ray detection and imaging. In this work, a series of manganese halides (CP1–CP5) with tetrahedral coordination structures were designed and synthesized by a facile room-temperature evaporation method. All of these complexes exhibit strong green emission around 512 nm, originating from d–d 4T1–6A1 transitions of Mn2+ centers, and possess high photoluminescence quantum yields of over 85%. CP1–CP5 exhibit strong radioluminescence under X-ray irradiation, and demonstrate excellent linear response to X-ray dose rate. Among them, CP5 demonstrates the optimal X-ray scintillation performance with a low detection limit of 17.96 nGyair s−1. Moreover, by employing CP5 film as a scintillator screen, high-resolution X-ray imaging of 4.35 lp mm−1 was accomplished. This work provides a new way for the preparation of simple and low-cost metal halides applied in X-ray imaging. [ABSTRACT FROM AUTHOR]

High activity hyper-crosslinked polymer solid acids (HCPSAs) were prepared from different aromatic monomers, and the structure was regulated by selecting the type and size of aromatic monomers. The results indicated that aromatic monomers affect not only the skeleton structure of HCPSAs, but also the loading of active groups significantly. The structural change of HCPSAs displayed a certain regularity as the size of the aromatic monomer increased; however, the catalytic activity of HCPSAs in oleic acid methylation and cellulose hydrolysis exhibited a different trend. HCPSA derived from thiophene presented the highest oleic acid conversion, while HCPSA prepared from phenanthrene showed the highest reducing sugar yield. The highly active HCPSA for a specific reaction can be obtained by controlling aromatic monomers. [ABSTRACT FROM AUTHOR]

Aqueous glycerol was used in this study as a liquid-phase hydrogen source for the hydrogenation of CO2. It was found that hydrogen could be efficiently evolved from aqueous glycerol upon highly dispersed Ru on layered double hydroxide (LDH), inducing the transformation of CO2 into formaldehyde under base-free conditions at low temperature. [ABSTRACT FROM AUTHOR]

Here we report on chelating ligands for Signal Amplification By Reversible Exchange (SABRE) catalysts that permit hyperpolarisation on otherwise sterically hindered substrates. We demonstrate 1H enhancements of ∼100-fold over 8.5 T thermal for 2-substituted pyridines, and smaller, yet significant enhancements for provitamin B6 and caffeine. We also show 15N-enhancements of ∼1000-fold and 19F-enhancements of 30-fold. [ABSTRACT FROM AUTHOR]

This review contributes towards a systematic understanding of the mechanism of shape-dependent effects on nanoparticles (NPs) for elaborating and predicting their properties and applications based on the past two decades of research. Recently, the significance of shape-dependent physical chemistry and biomedicine has drawn ever increasing attention. While there has been a great deal of effort to utilize NPs with different morphologies in these fields, so far research studies are largely localized in particular materials, synthetic methods, or biomedical applications, and have ignored the interactional and interdependent relationships of these areas. This review is a comprehensive description of the NP shapes from theory, synthesis, property to application. We figure out the roles that shape plays in the properties of different kinds of nanomaterials together with physicochemical and biomedical applications. Through systematic elaboration of these shape-dependent impacts, better utilization of nanomaterials with diverse morphologies would be realized and definite strategies would be expected for breakthroughs in these fields. In addition, we have proposed some critical challenges and open problems that need to be addressed in nanotechnology. [ABSTRACT FROM AUTHOR]

A titanium–vanadium–molybdenum (V2O5–MoO3/TiO2) SCR (selective catalytic reduction) catalyst has been confirmed to be effective for mercury oxidation in 6% O2/N2 atmosphere, but the influence of the actual flue gas components on mercury oxidation over this catalyst has not been reported. The individual flue gas components can significantly influence the mercury oxidation ability of the SCR catalyst. In this study, the effect of individual flue gas components on V2O5–MoO3/TiO2 for mercury oxidation was evaluated. The results suggested that the mercury oxidation efficiency of V2O5–MoO3/TiO2 was over 95% in the presence of 20 ppm HCl. The process of mercury oxidization by HCl over V2O5–MoO3/TiO2 followed the Langmuir–Hinshelwood mechanism. O2 was critical in this process, and we could continue catalytic recycling by re-oxidizing the reduced lattice oxygen. NH3 and H2O, especially H2O, suppressed the mercury oxidation ability of the catalyst. The mercury oxidation ability of V2O5–MoO3/TiO2 was almost lost in the presence of 8% H2O. Even after elimination of H2O, the mercury oxidation efficiency only recovered to 55%. This was due to the competition of NH3 or H2O with Hg0 for the same active sites on the surface of the catalyst. Unfortunately, H2O caused irreversible damage to the active sites. Additionally, the mercury oxidation efficiency was over 60% even with the existence of high SO2 content. This indicated that this catalyst can display some degree of sulfur resistance. [ABSTRACT FROM AUTHOR]

The reactive oxygen species (ROS)-mediated mechanism is the major cause underlying the efficacy of photodynamic therapy (PDT). The PDT procedure is based on the cascade of synergistic effects between light, a photosensitizer (PS) and oxygen, which greatly favors the spatiotemporal control of the treatment. This procedure has also evoked several unresolved challenges at different levels including (i) the limited penetration depth of light, which restricts traditional PDT to superficial tumours; (ii) oxygen reliance does not allow PDT treatment of hypoxic tumours; (iii) light can complicate the phototherapeutic outcomes because of the concurrent heat generation; (iv) specific delivery of PSs to sub-cellular organelles for exerting effective toxicity remains an issue; and (v) side effects from undesirable white-light activation and self-catalysation of traditional PSs. Recent advances in nanotechnology and nanomedicine have provided new opportunities to develop ROS-generating systems through photodynamic or non-photodynamic procedures while tackling the challenges of the current PDT approaches. In this review, we summarize the current status and discuss the possible opportunities for ROS generation for cancer therapy. We hope this review will spur pre-clinical research and clinical practice for ROS-mediated tumour treatments. [ABSTRACT FROM AUTHOR]

We report a simple strategy to construct a multiple gadolinium complex decorated fullerene (CGDn) as an enhanced T1 contrast agent. The CGDn exhibits much higher T1 relaxivity (∼49.7 mM−1 s−1) than individual Gd-DOTA, and shows excellent T1 contrast enhancement ability both in vitro and in vivo. [ABSTRACT FROM AUTHOR]

Aqueous glycerol was used in this study as a liquid-phase hydrogen source for the hydrogenation of CO 2 . It was found that hydrogen could be efficiently evolved from aqueous glycerol upon highly dispersed Ru on layered double hydroxide (LDH), inducing the transformation of CO 2 into formaldehyde under base-free conditions at low temperature.

Photoacoustic imaging combines the merits of ultrasound imaging and optical imaging that allows a fascinating imaging paradigm with deeper tissue penetration than optical imaging and higher spatial resolution than ultrasound imaging. Herein, we develop a supramolecular hybrid material composed of graphene oxide (GO) and a pillar[6]arene-based host-guest complex (CP6⊃PyN), which can be used as a ultrasound (US) and photoacoustic (PA) signal nanoamplifier. Triggered by the near-infrared (NIR) light mediated photothermal effect, CO 2 nanobubbles are generated on the surface of GO@CP6⊃PyN due to the decomposition of bicarbonate counterions, thus strongly amplifying its US and PA performances. Our study, for the first time, demonstrates enhanced US and PA activity in supramolecular hybrid material on the basis of host-guest chemistry as a photoacoustic nanoplatform., Competing Interests: Conflicts of interest There are no conflicts to declare.

Tracking of cells in biological systems is critically important for monitoring disease treatment, such as in stem cell therapy. This report prepared new types of biocompatible gadolinium hybrid iron oxide (GdIO) nanocomposites, which demonstrated high sensitivity for dual T 1 - and T 2 -weighted magnetic resonance imaging (MRI). The GdIO nanocomposites could efficiently label mesenchymal stem cells (MSCs) by incubation for 24 h at a safe dose, as they did not affect the cell viability, proliferation or differentiation capacity. There was high contrast enhancement in the GdIO-labeled stem cells for dual T 1 - and T 2 -weighted MR imaging. In addition, the GdIO nanocomposites were injected into adult mouse lateral ventricles, where cells could be labeled to monitor their biological behaviors by MRI. These GdIO nanocomposites with dual-imaging functions are a good platform for cell labeling and other diagnostic applications.

We report a simple strategy to construct a multiple gadolinium complex decorated fullerene (CGDn) as an enhanced T1 contrast agent. The CGDn exhibits much higher T1 relaxivity (∼49.7 mM(-1) s(-1)) than individual Gd-DOTA, and shows excellent T1 contrast enhancement ability both in vitro and in vivo.