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A novel click-based bioactive injectable hydrogel based on two PEG derivatives realizes the efficient loading of rBMSCs and spatiotemporal delivery of rhBMP-2, basically accomplishing repair and regeneration of a critical-size defect within 4 weeks.

Fluorinated saccharide-derived hard carbon is prepared as a cathode material of lithium primary batteries, and the effect of the polymerization degree of the starting saccharide is investigated.

SiO2@Au nanoshell assisted laser desorption/ionization time-of-flight mass spectrometry was used to extract metabolic fingerprints of patients with coronary heart disease with high fidelity and minimum sample pretreatment.

A butterfly-like FeNi/Ni HS featuring a “torso” of Ni-doped FeOOH and two “wings” of Ni2(CO3)(OH)2 showed excellent activity in electrocatalytic oxygen evolution reaction attributable to the increase of higher-valance Ni3+ in the heterostructure.

Unique 2D ternary hierarchitectures constructed from reduced graphene oxide nanosheets grown with ultrathin Cd0.15Zn0.85In2S4 nanosheets and Ni2P nanoparticles exhibited an outstanding capability for visible-light photocatalytic H2 production.

The full width at half maximum is increased by introducing Sc3+ regulating the crystal field environment around Cr3+ in SrGa12O19:Cr3+. Meanwhile, a promising application potential in night vision lighting and bioimaging has been demonstrated.

A reinforced concrete inspired Si/rGO/cPAN hybrid electrode is achieved to build robust transport charge pathways for high-capacity binder-free lithium battery anodes.

Optoelectronic properties of metal halide perovskites were modulated using Sn-doping. Photoconductors were fabricated based on the Sn-doped perovskite films, and the devices were optimized to present weak temperature-dependent performance metrics.

Photocatalytic water-splitting with Z-scheme semiconductor heterojunctions is a promising way to achieve renewable solar fuels. Nevertheless, developing earth-abundant direct Z-scheme photocatalytic systems for efficient H2 production is still under-developed. In this work, porous heterostructures of S-deficient CoS/CdS hexagonal nanoplates (HNPs) were fabricated for the first time through the self-template approach combined with a solvothermal process. As indicated by the scanning Kelvin probe microscopy and ∙OH radicals measurements, such CoS/CdS heterojunction follows the Z-scheme charge transfer pathway. Noticeably, these unique CoS/CdS HNPs demonstrated excellent photocatalytic activity and stability for H2 evolution reaction (HER) under visible-light irradiation (λ > 400 nm). Specifically, the optimal HER rate is as high as 39.29 mmol∙g-1∙h-1 (corresponding to the apparent quantum yield of 14.5% at 400 nm), approximately 152, 112, and 51 times that of CoS, CdS, and 3 wt% Pt-loaded CdS, respectively. The exceptional HER capability of CoS/CdS HNPs could be associated with their outstanding visible-light harvesting, efficient Z-scheme charge separation, and abundant H2 evolution active sites. The findings indicated here could impel the rational design of high-performance Z-scheme photocatalysts for energy and environmental applications.

Unique Cd0.5Zn0.5S/WO3−x direct Z-scheme heterojunction with S, O vacancies and zinc blende/wurtzite twinning superlattices exhibited a dramatically heightened capability toward visible-light photocatalytic H2 generation.

The hollow core–shell Mo-NiSx@NiFe LDH/NF catalyst combining the intrinsic merits of sulfides and LDH exhibits fast reaction kinetics and electrochemical activity, leading to enhanced activity for the OER and HER and superior stability.

Two-dimensional (2D) semiconductor nanostructures have exhibited great prospect as an efficient photocatalyst for solar-to-fuel application. In this work, a unique 2D tandem heterojunction consisting of ultrathin CdxZn1−xIn2S4 nanosheets coupled with rectangular CdS flakes and defect-rich MoS2 few-layered nanosheets was constructed for the first time. Remarkably, the efficient electron transfer channels present in the CdS/CdxZn1−xIn2S4 and CdxZn1−xIn2S4/MoS2 2D tandem heterojunctions facilitate the spatial separation and directional migration of photo-induced charge carriers effectively. Moreover, such 2D tandem heterojunction CdxZn1−xIn2S4–CdS–MoS2 is provided with excellent light harvesting capacity and abundant HER active sites from the defective MoS2 co-catalyst. These distinct advantages endow the optimized C0.15ZIS–5C–3M hybrid (5 wt% CdS, 3 wt% MoS2) with an exceptional photocatalytic H2 evolution reaction (HER) activity of 27.14 mmol h−1 g−1, approximately 47 times that of pure ZnIn2S4 and it is much superior to that of Pt-decorated C0.15ZIS–5C and most ZnIn2S4-based composites reported previously. A high HER apparent quantum yield (AQY) of 19.97% is achieved at λ = 400 nm. In addition, both the cycling and long-term HER measurements evidence the prominent stability of C0.15ZIS–5C–3M for H2 production. The results indicated here could pave the way for the exploitation of new 2D heterostructures toward highly-efficient solar conversion and utilization.

The development of high quantum efficiency and stable red emitting phosphors with high color purity is an urgent need for multifunctional optical applications. In this work, we propose a nonlinear optical material (NLOM)-inspired methodology to synthesize a novel red emission pyrophosphate phosphor Rb2Ba3(P2O7)2:Eu3+. XRD Rietveld refinement and energy dispersive X-ray spectroscopy were then exploited to obtain information on the phase purity, crystal structure and chemical composition. Moreover, the optical bandgap of different Eu3+ doped Rb2Ba3(P2O7)2 phosphors was analyzed by diffuse reflectance spectroscopy and further confirmed by first principles calculation. Furthermore, the Eu3+ site occupation preference, the characteristic luminescence properties and luminescence kinetics as a function of Eu3+ doping concentration were investigated by employing the cryogenic spectra at 4 K, room temperature emission spectra and decay curves. The luminescence analysis indicated that Rb2Ba3(P2O7)2:Eu3+ could emit red emission light with high quantum efficiency (IQE ∼ 77.04%), high color purity (96.4%) and excellent thermal stability (87%@ 140 °C) under ultraviolet light excitation. In addition, the excellent stability of Rb2Ba3(P2O7)2:Eu3+ against external pressure, cathode-ray irradiation, water and acid–base was further proved by pressure-driven (from 0 to 20 GPa) luminescence analysis, cathodoluminescence analysis and emission photography after infiltrating in water, acid, and alkali. The current work indicates that Rb2Ba3(P2O7)2:Eu3+ exhibits unprecedented excellent luminescence properties compared to other recently discovered phosphate red phosphors, and can serve as a potential red phosphor candidate in multifunctional optical applications, like LEDs, FEDs, artistic appreciation or some applications under extreme conditions (high temperature, strong pressure, and infiltrating in water, acid, and alkali).

There is an urgent need to develop phosphors with high quantum efficiencies (QEs) since white light-emitting diodes (WLEDs) have emerged as a new generation of illumination materials. Utilizing energy transfer to improve the absorption of activators and adjust the emission colors of samples is one effective strategy. Here, color-tunable phosphors of the form CaAl4O7:Ce,Tb were synthesized aiming at efficient energy transfer from Ce3+ to Tb3+. Since Tb3+ can be suitably sensitized by Ce3+, the co-doped phosphors can be effectively excited by near-ultraviolet (NUV) light. The internal QE of CaAl4O7:0.04Ce,0.04Tb under 350 nm excitation is as high as 92.55%, and the external QE is 71.02%. A WLED fabricated from BAM:Eu2+, CaAl4O7:0.04Ce,0.04Tb, and CaAlSiN3:Eu2+ with a 365 nm LED chip exhibited a correlated color temperature (CCT) of 4706 K and a color rendering index (CRI, Ra) of 81.44. The energy transfer mechanism and thermal stability of the phosphor were also investigated. The results provide an effective approach for developing highly efficient green-emitting phosphors for NUV WLEDs.

The combination of binary complementary color phosphors with near-ultraviolet (NUV) light-emitting diode (LED) chips was put forward to lower the energy loss caused by the reabsorption of the combination of tricolor phosphors with NUV LED chips. Thus investigating broadband yellow-emitting phosphors with enriched red components in the spectral range has gained much attention. Here, an extremely broadband yellow-emitting phosphor Sr8MgCe(PO4)7:Eu2+ with sufficient red component in the spectral region was synthesized. Due to the introduction of Ce into the host, Sr8MgCe(PO4)7 shows an emission band with a peak at 375 nm when excited at 310 nm. Meanwhile, Eu2+ doped Sr8MgCe(PO4)7 exhibits an extremely broad yellow emission band with a full width at half-maximum of 175 nm and a peak located at about 598 nm, due to the 5d–4f transitions of Eu2+ ions substituting five Sr2+ sites. The excitation peak of the host at 310 nm was detected in the excitation spectrum of Sr8MgCe(PO4)7:Eu2+ monitored at 598 nm, indicating the energy transfer from the host to Eu2+, which was also proved by the decay curves. On the other hand, the excitation band at about 400 nm due to the 4f–5d transitions of Eu2+ was also detected in the excitation spectrum of Sr8MgCe(PO4)7:Eu2+, and this matches well with the NUV LED chips. Moreover, the energy transfer between Eu2+ ions at different crystallographic sites was demonstrated by time-resolved photoluminescence (TRPL) spectra. A white LED with a CRI (Ra) of 82.88 and a CCT of 4238 K was prepared through a 400 nm NUV LED chip, Sr8MgCe(PO4)7:Eu2+ and BaMgAl10O17:Eu2+ (BAM:Eu2+). These results pave the way for designing better Eu2+-doped phosphors for NUV WLEDs with binary complementary color phosphors.

The luminescence of dielectric phase transition materials is one important property for technological applications, such as low-energy electron excitation. The combination of dielectric phase transitions and luminescence within organic–inorganic hybrids would lead to a new type of luminescent dielectric phase transition multifunctional material. Here, we report two novel A2BX4 organic–inorganic hybrid complexes [Me3NVinyl]2[MnCl4] 1 and [Me3NVinyl]2[MnBr4] 2, ([Me3NVinyl] = trimethylvinyl ammonium cation). The complexes 1 and 2 were found to undergo continuous reversible phase transitions as well as switch dielectric phase transitions. Strikingly, intensive red luminescence and green luminescence were obtained under UV excitation respectively to reveal potential application of the two complexes in multi-functional materials along with dielectric switches and so on.

Implantable probes and needles represent multifunctional biomedical platforms by integrating sensing, stimulation, and drug delivery capabilities. Conventional rigid probes often result in inflammatory responses due to large mechanical mismatch with soft biological tissues, whereas soft probes with improved long-term performances are difficult to be inserted deep into the compliant biological tissues. An emerging class of mechanically transformative materials addresses the challenge by embedding a phase-change material of gallium within an elastomeric matrix. These materials exhibit high stiffness under ambient conditions to enable facile insertion and compliant mechanical properties after implantations. The widespread implementation of mechanically transformative materials is primarily hindered by the lack of facile fabrication techniques for delicate gallium features. In this study, we introduce a solution-based approach for scalable fabrication of gallium-based mechanically transformative materials, which exhibit bistable mechanical properties with large modulations in the modulus by five orders of magnitude. In a solution-based coating process, gallium features are created based on a patterned copper film and then encapsulated with elastomers to form mechanically transformative materials. The height profile of the gallium feature is controlled by the two-dimensional design of the copper pattern, which provides access to delicate and complex three-dimensional features as exemplified by mechanically transformative indwelling needles with sharp tips. The practical suitability is demonstrated by the in vivo implementation of the indwelling needles for long-term chemotherapy. The excellent biocompatibility enables applications of mechanically transformative biomedical devices in chronic implantable systems.

Photocatalytic solar-to-fuel conversion has been of great interest in recent years. Nevertheless, the rational structural manipulation of photocatalysts toward an efficient H2 evolution reaction (HER) is still under-developed. In this work, by employing CdS nanowires as the growth substrate, unique one-dimensional (1D) CdS@Cd0.5Zn0.5S@ZnS-Ni(OH)2 heterostructures were first synthesized through the ultrasonic water-bath reaction combined with subsequent hydrothermal and in situ photo-deposition processes. Under the optimized conditions, CS@30CZ0.5S@40ZS-3N with 30 wt% Cd0.5Zn0.5S, 40 wt% ZnS, and 3 wt% Ni(OH)2 achieves a visible-light-driven HER activity as high as 86.79 mmol h−1 g−1 (corresponding to an apparent quantum yield of 22.8% at 420 nm), which is 4 and 119 times higher than that of Pt-decorated CS@30CZ0.5S@40ZS and CdS, respectively. In addition, CdS@Cd0.5Zn0.5S@ZnS-Ni(OH)2 is also endowed with a good stability for H2 production under long-term irradiation. The spatial separation of photo-redox sites and epitaxial heterointerfaces in CdS@Cd0.5Zn0.5S@ZnS-Ni(OH)2 nanowires facilitate the charge transfer and separation effectively, accounting well for their superior photocatalytic capability. The results indicated in this work could benefit the exploitation of high-performance nanostructures for promising photocatalytic applications.

Solar-driven photocatalytic water-splitting for H2 production holds great promise to alleviate the growing energy and environmental crisis. Nevertheless, it is still challenging up to now to develop noble-metal-free photocatalysts which are efficient for the H2 evolution reaction (HER). In this work, based on the ion-exchange and alloying reactions between Zn and Cd ions in liquids, a template-assisted ion-exchange strategy combined with subsequent electrostatic assembly process was employed to prepare uniform ZnS@CdS@Cd0.5Zn0.5S-MoS2 hollow nanospheres for the first time. Under visible-light irradiation (λ > 420 nm), the ZnS@CdS@Cd0.5Zn0.5S-MoS2 hybrid exhibits an optimal HER activity of 50.65 mmol h−1 g−1, which is 20 times more than that of its Pt-decorated ZnS@CdS@Cd0.5Zn0.5S counterpart and superior to that of most CdS-based photocatalysts ever reported. Moreover, the ZnS@CdS@Cd0.5Zn0.5S-MoS2 hybrid exhibits good stability for the long-term HER. The outstanding HER capability of ZnS@CdS@Cd0.5Zn0.5S-MoS2 could be attributed to the dramatically facilitated separation of charge carriers, abundant active sites from the defect-rich 1T/2H MoS2 few-layered nanosheets, and enhanced light-harvesting of the hollow nanostructure. The findings indicated here could benefit the exploitation of high-performance photocatalysts for promising solar-to-fuel applications.

Development of noble-metal-free photocatalysts for efficient H2 production from sunlight-driven water-splitting has aroused great interest in recent years. Herein, unique Cd0.5Zn0.5S@ZnS core–shell nano-spheres decorated with Ni2P and g-C3N4 cocatalysts were prepared for the first time, and they are highly active and stable toward the visible-light-driven (λ > 420 nm) H2 evolution reaction (HER). Noticeably, the optimized Cd0.5Zn0.5S@ZnS-Ni2P/g-C3N4 with 50 wt% ZnS, 3 wt% Ni2P, and 8 wt% g-C3N4 (CZ0.5S@50ZS-3N/8CN) exhibits a superior HER activity of 55.43 mmol·g−1·h−1, approximately 25 and 18 times higher than those of CZ0.5S@50ZS and Pt-decorated CZ0.5S@50ZS (CZ0.5S@50ZS-Pt), respectively. Meanwhile, the corresponding apparent quantum yield (AQY) at 420 nm is as high as 21%. It is revealed that the protective ZnS shell on the CZ0.5S core enhances the photo-stability of the hybrid significantly. Moreover, the synergistic effect of the Ni2P and g-C3N4 cocatalysts leads to the effective transfer and separation of charge carriers. The results presented in this work may pave the way for the ingenious design and fabrication of highly active nano-structures for sufficient solar utilization.

To explore different photoluminescence phenomenon of Ti4+ ions, a rare-earth-free self-activated phosphor Li2TiSiO5 was synthesized and studied in detail. The crystal structure, photoluminescence properties and thermal quenching of Li2TiSiO5 were discussed. The crystal structure has been investigated by Rietveld refinement, and this indicates that there is a special kind of TiO5 square pyramids in this structure. Under 245 nm excitation, Li2TiSiO5 emits white light ranging from 400 to 780 nm with CIE coordinates of (0.388, 0.441), which is due to the existence of isolated TiO5 square pyramids and TiO6 octahedra in the disordered non-crystalline powder, which is also proved by the time-resolved photoluminescence. The abnormal serious thermal quenching is ascribed to thermal ionization. The study of Li2TiSiO5 broadens the research of rare-earth-free Ti-doped oxides due to its self-activated luminescence and the realization of white light emission in a single host.

Chalcogenides have attracted great attention in the past few decades because of their excellent processability and outstanding optoelectronic properties. Particularly, AgBiS2 has been the frontier of the photovoltaic field in the past few years. AgBiS2 possesses fascinating merits, such as a high absorption coefficient, suitable bandgap, decent charge transport properties and superior material stability. However, most of the efficient AgBiS2-based devices are fabricated with AgBiS2 quantum dots, which require long fabrication time and complicated synthetic steps. Moreover, most of the reports focused on photovoltaic devices, and AgBiS2-based photodetectors have not been reported yet. Based on the challenges listed above, we developed AgBiS2 photodetectors based on a molecular precursor method with a p–i–n device structure. These photodetectors exhibited broadband spectral response with decent detectivity and fast response time of 700 ns. In addition, these devices also demonstrated outstanding air, light and water stability.

Methylglyoxal (MGO) is the main antimicrobial determinant associated with using Mānuka Honey as a topical dressing. While direct mechanisms of Mānuka honey MGO's antimicrobial activity have been demonstrated, such as disruption of bacterial fimbria and flagella, no interaction of Mānuka honey-derived MGO with antimicrobial effector cells of the immune system, such as mucosal-associated invariant T cells (MAIT cells), has yet been reported. MAIT cells are an abundant subset of human T cells, critical for regulating a diverse range of immune functions, including antimicrobial defense mechanisms but also mucosal barrier integrity. MAIT cells become activated by recognition of an important microbial metabolite, 5-amino-6-d-ribitylaminouracil (5-A-RU), which is produced by a wide range of microbial pathogens and commensals. Recognition is afforded when 5-A-RU condenses with mammalian-cell derived MGO to form the potent MAIT cell activator, 5-(2-oxopropylideneamino)-6-d-ribitylaminouracil (5-OP-RU). Formation of 5-OP-RU and its subsequent presentation to MAIT cells by major histocompatibility (MHC)-related molecule 1 (MR1) facilitates host-pathogen and host-commensal interactions. While MGO is a metabolite naturally present in mammalian cells, it is unclear whether exogenous dietary MGO sources, such as those obtained from Mānuka honey intake, can contribute to 5-OP-RU formation and enhance MAIT cell activation. In this work, we report that endogenous MGO is the rate-limiting substrate for converting microbial 5-A-RU to 5-OP-RU and that Mānuka honey-derived MGO significantly enhances MAIT cell activation in vitro. Our findings posit a novel mechanism by which intake of a food item, such as Mānuka honey, can potentially support immune homeostasis by enhancing MAIT cell-specific microbial sensing.

The rational design and synthesis of low-dimensional chalcogenides with desired properties is vital but still an enormous challenge. Herein, a novel quaternary sulphide, Ba8Zn4Ga2S15 (FJ-2), has been designed by a cation regulation strategy and successfully prepared. It comprises a one-dimensional (1D) {[Zn4Ga2S15]16-}∞ anion chain constructed from supertetrahedron [Zn4S10] clusters. The structure of FJ-2 is unique, as in the literature there are no other 1D structures of the type X/Zn/Ga/Q (X = cations; Q = chalcogen). Moreover, FJ-2 exhibits strong yellow photoluminescence emission at room temperature. DFT calculations using the VASP software package have aided the understanding of the relationship between the optical properties and electronic structure.

The lithium/fluorinated carbon (Li/CFx) battery is a widely used solid-state lithium primary battery (LPB) with the highest ever known specific energy. However, the scarcity of lithium resources compels researchers to explore other types of batteries. Sodium batteries have been considered as the most suitable candidate power sources due to the low cost of sodium and its similar chemistry to lithium. In this work, we prepared two series of fluorinated carbon nanotubes (CNTs), which are fluorinated common CNTs (FCNT-x) and fluorinated graphitized CNTs (FGCNT-x). The effects of graphitization of the CNTs on the structure of fluorinated carbon nanotubes and C–F bonding are systematically studied. FGCNT-x prepared from the graphitized CNTs exhibit a lower ratio of F/C and weaker C–F bonding than those of the FCNT-x prepared from ordinary CNTs at the same fluorination temperature. FGCNT-0.81 exhibits very high specific capacities of 798.8 and 751 mA h g−1 in lithium and sodium primary batteries, nearly reaching the theoretical capacity calculated using the F/C ratio. Besides, FGCNT-0.81 possesses a maximum energy density of 2006.6 W h kg−1 in Li/CFx batteries and 1733.4 W h kg−1 in Na/CFx batteries. The maximum power density for Li/CFx and Na/CFx batteries could reach up to 3861.1 (FCNT-0.81) and 1863.9 W h kg−1 (FGCNT-0.81), respectively. It is proved that the binding energy of the C–F bond, the electronegativity and the polarization force of the metal ions collaboratively determine the electrochemical performance of the fluorinated CNTs. The new-type Na/CFx primary batteries developed here are promising in low power applications such as high-energy density and low-cost batteries.

Considering the intrinsic complexity of cancer, the emergence of multifunctional nanocarriers provides more possibilities for cancer therapy. Herein, a novel multifunctional nanocarrier (g-CNQDs–PEG–RGD) is successfully developed by covalently grafting graphitic-C3N4 quantum dots (g-CNQDs) with arginine–glycine–aspartic acid (RGD) via diamine-terminated oligomeric polyethylene glycol (PEG). The functionalization of g-CNQDs with PEG and RGD imparts the nanocomposite with low cytotoxicity, excellent physiological stability and specific targeting ability toward cancer cells with the αvβ3 receptor. The widely used fluorescent antineoplastic anthracycline drug doxorubicin (DOX) is non-covalently loaded onto g-CNQDs–PEG–RGD. It is advantageous that the g-CNQDs–PEG–RGD–DOX nano-assembly exhibits enhanced cellular uptake by HepG2 cells, which overexpress integrin αvβ3 receptors. Thus, the enhanced targeting specificity and intracellular acid condition-triggered drug release promise excellent therapeutic effects. Meanwhile, the inherent stable fluorescence of g-CNQDs–PEG–RGD and DOX enables real-time monitoring of cellular uptake of the g-CNQDs–PEG–RGD–DOX nano-assembly, consequent release of DOX and the fate of the carrier. These findings demonstrate that g-CNQDs–PEG–RGD–DOX will be promising for high treatment efficacy with minimal side effects in future therapy.

The stretchable version of electronic circuits harnesses commercial chip scale components to achieve complex functionality and mechanical deformability, which represents an emerging technology to expand the application of conventional electronics on rigid wafers. The bottleneck lies in the lack of a robust approach for the collective integration of off-the-shelf components into a reliable system. In this study, an elastomeric composite material with skin-like mechanical responses and spatially heterogeneous rigidity is reported as an attractive platform for stretchable circuit systems. The approach utilizes a high modulus microstructure embedded in the matrix of a soft elastomer to achieve programmable mechanical properties, thereby offering selective strain isolation for fragile components and overall protection against excessive loads. A low cost procedure involving laser ablation and blade coating is established to create the composite material matching with the circuit design. In addition, ultrasonic atomization of liquid metal into microparticles allows flexible preparations of deformable conductors in the forms of interconnects and contacts. An LED matrix is demonstrated as a prototype circuit system with excellent durability to withstand repetitive stretching and external impacts. Stretchable circuit systems based on soft elastomeric composite materials may find potential uses in health monitoring, mechatronic prosthetics, and soft robotics.

Herein, we synthesized and characterized NiFe2O4-based magnetic nanoparticles (MNPs) and used these MNPs in an effervescent tablet-assisted dispersive solid-phase microextraction (MNET-DSPM) method for preconcentration/extraction of trace Cu, Mn, Zn and Cd ions prior to inductively coupled plasma mass spectrometry (ICP-MS) detection of seafood. A 0.2 g magnetic effervescent tablet (8 mm diameter × 2 mm thickness) consisted of Na2CO3, NaH2PO4 and NiFe2O4 MNPs. In the MNET-DSPM method, NiFe2O4 was used as both the adsorbent and the magnetic separation agent with the aid of CO2 released by reaction of an acid source and a base source. This is done so as to avoid utilization of additional energy sources and chelating agents. Moreover, this newly developed method has many advantages such as having no need for complex devices or instrumentation, easy operation in a magnetic field, high sensitivity/accuracy and short extraction time by the dispersion of effervescent tablets and adsorption of MNPs. Several important parameters were optimized using the one-factor-at-a-time approach. Under the optimized conditions, the MNET-DSPM/ICP-MS method gave LODs for the four metal ions as low as 0.007–0.018 μg kg−1, extraction recoveries of 73.4–99.3%, and high precisions with intra- and inter-day RSDs of 1.5–6.1%. Cu, Mn and Zn ions in shrimp, squid, shellfish and little yellow croaker samples were detected to be in the range of 1.92–173.53 μg kg−1. To our knowledge, this is the first time that a NiFe2O4-based effervescent microextraction for detection of metal ions in seafood is developed. Based on a series of superior analytical performances, this MNET-DSPM/ICP-MS method will have a great potential application value in routine pollution monitoring of seafood.

The volumetric capacity of lithium-ion batteries is becoming an increasingly important parameter restricting their practical applications in limited space, such as in portable electronic products and electric vehicles. Therefore, novel electrode materials with high volumetric capacities are urgently desirable. Aiming to pursue such kind of electrode materials, a new Fe3O4@Ti3C2 MXene hybrid is fabricated through a simple ultrasonication of Ti3C2 MXene and Fe3O4 nanoparticles. Multi-layered Ti3C2 MXene in the prepared hybrids acts as a superior host to load Fe3O4 nanoparticles due to its open two dimensional structure, favorable electrical conductivity and low Li+ diffusion barrier. X-ray diffraction and scanning electron microscopy analysis show that the Ti3C2 MXene could be homogeneously covered by Fe3O4 nanoparticles at a mass ratio of 5 : 2. As an anode material, the Fe3O4@Ti3C2-2:5 hybrid exhibits high reversible capacities of 747.4 mA h g−1 at 1C after 1000 cycles and 278.3 mA h g−1 at 5C after 800 cycles, which indicate its long cycle lifetime and excellent stability. More importantly, the hybrid material possesses an outstanding volumetric capacity up to 2038 mA h cm−3 at 1C due to the high compact density of the electrode of the prepared hybrid. This study provides further insight into the application of transition metal oxides@MXene hybrids as high volumetric performance anode electrodes for lithium-ion batteries.

Renewable biomass as a precursor in the preparation of sustainable carbon materials for supercapacitors has gained much attention due to its huge reserves and being economical. In this paper, we used waste printing paper as the precursor to prepare highly porous carbons via a combined method of pre-carbonation and KOH activation. The prepared carbon materials exhibit huge specific surface areas and good conductivities as high as 2616.1 m2 g−1 and 198.8 mS cm−1, respectively. They were used as the electrode materials of supercapacitors in the most common aqueous electrolytes, including 6 M KOH, 1 M H2SO4, and 1 M Na2SO4, and showed excellent capacitive performance in all the investigated electrolytes, such as very high specific capacitances (e.g. 385.0, 370.1, and 317.7 F g−1 in KOH, H2SO4 and Na2SO4 electrolyte at 0.2 A g−1, respectively), outstanding rate capabilities (e.g. 198 F g−1 at 60 A g−1 in H2SO4), high energy densities (e.g. 21.9 W h kg−1 in Na2SO4), high power capability (at 28 000 W kg−1, remains at 5.83 W h kg−1 in Na2SO4), and good recyclability (about 94% retention after 10 000 cycles).

Although calcium phosphate (CaP) ceramics have been originally defined as bioactive materials because a biologically active hydroxycarbonate apatite (HCA) layer can form on their surfaces, the biological effects of the as-grown HCA layers are far from understood. In particular, it is unclear whether the as-grown HCA nanotopography can mediate the osteogenic commitment of mesenchymal stem cells (MSCs). In this study, a systematic investigation was performed to investigate the formation and biological effects of HCA nanotopography on CaP ceramic surfaces. Experiments demonstrate that the hydroxyapatite phase-containing CaP ceramics tend to grow HCA nanoparticle-constructed nanotopography, which can mediate bone marrow MSCs to condensate and spontaneously differentiate toward osteogenic lineage. In addition, the biological evolution of MSCs adhered on such nanotopography is similar to intramembranous ossification. Our findings provide support for applications of wurtzite phase-containing CaP ceramics in regenerative medicine for hard tissues.

Enabling the optimal usage of solar energy is considered to be one of the most pressing challenges in the photocatalytic remediation of water resident contaminants. Herein, a single-atom dispersed Ag loaded ultrathin g-C3N4 hybrid (AgTCM/UCN) was prepared through a facile co-polymerization of dicyandiamide with silver tricyanomethanide (AgTCM) and NH4Cl, and used as a visible light driven photocatalyst for the degradation of sulfamethazine (SMT) in the presence of peroxymonosulfate (PMS). Under UV light, visible light and simulated sunlight irradiation, the AgTCM/UCN/PMS process showed higher efficiency for SMT degradation than AgTCM/UCN, UCN/PMS, and g-C3N4/PMS systems. This enhanced photocatalytic activity may be attributed to the synergistic effects encompassing the surface plasmon resonance (SPR) of Ag, high surface area of UCN, and efficient charge separation of PMS. Electron-spin resonance (ESR) and reactive species (RSs) scavenger-quenching experiments revealed that SO4˙- was generated following the addition of PMS, whereas O2˙- and h+ were predominantly responsible for the degradation of SMT. Three degradation pathways of SMT were deduced, including the cleavage of sulfonamide bonds, SO2 extrusion, and the oxidation of the aniline moiety, based on mass spectrometry and theoretical calculations. The degradation of SMT in ambient water revealed that the AgTCM/UCN/PMS photocatalytic process can be efficaciously applied for the remediation of SMT contaminated natural waters, particularly sea water.

This study evaluated the effects and related mechanisms of natural organic matter (NOM) on the photolysis of methyltriclosan (MTCS), a metabolite of triclosan. Addition of two representative NOM isolates, Pony Lake fulvic acid (PLFA-microbial origin) and Suwannee River fulvic acid (SRFA-terrestrial origin), significantly inhibited the direct photolytic rate of MTCS by ∼70%. The MTCS photolytic rate in the presence of PLFA was greater than for SRFA. NOM not only suppressed photolysis by light-shielding, but also produced ROS to oxidatively degrade MTCS and/or triplet NOM (3NOM*) to sensitize degradation. The dual effects of light-screening and photo-sensitization led to an overall decrease in photolysis of MTCS with a positive concentration-dependence. Upon addition of NOM, EPR documented the occurrence of 1O2 and ˙OH in the photolytic process, and the bimolecular k value for the reaction of 1O2 with MTCS was 1.86 × 106 M−1 s−1. ROS-quenching experiments indicated that the contribution of ˙OH (19.1–29.5%) to indirect photolysis of MTCS was lower than for 1O2 (38.3–58.7%). Experiments with D2O further demonstrated that 1O2 participated in MTCS photodegradation. Moreover, the addition of sorbic acid and O2 gas to the reaction confirmed the participation of 3NOM* as a key reactant in the photochemical transformation of MTCS. This is the first comprehensive analysis of NOM effects on the indirect photolysis of MTCS, which provides new insights for understanding the environmental fate of MTCS in natural environments.

Hydrolysate is a mixture of various peptides with specific functions. However, functional identification of hydrolysate with high throughput is still a difficult task. Furthermore, using in vivo tests via animal or cell experiments is time and labor-intensive. In this study, the peptides component of hydrolysate derived from the tuna dark muscle was measured via MALDI-TOF/TOF-MS, and the functions of the KEFT (Lys-Glu-Phe-Thr), EEASA (Glu-Glu-Ala-Ser-Ala) and RYDD (Arg-Tyr-Asp-Asp) peptides, which were found with the highest proportion, were predicted via Discovery Studio 2016 software. All three peptides were predicted to bind to the Keap1 protein with the highest fit-value and to affect the activity of Keap1, which is involved in anti-oxidation pathways. Subsequently, mice experiments showed that administration of tuna dark muscle hydrolysate increased the levels of superoxide dismutase and glutathione peroxidase in the serum and liver (P 0.05), which are consistent with the in silico analysis results using Discovery Studio 2016 software. The combination of in silico analysis and in vivo tests provided an alternative strategy for identifying hydrolysate function and provided insight into high-value utilization of protein hydrolysate.

Extending the spectral absorption of organic–inorganic mixed-cation perovskite solar cells (PSCs) from visible light to the near-infrared (NIR) range minimizes the nonabsorption loss of solar photons. Few studies have focused on the application of high-fluorescence NaYbF4:Ho3+ upconversion nanoparticles (UCNPs) in solar cells. In this study, NaYbF4:Ho3+ UCNPs were successfully prepared using a solvothermal method. We incorporated the NaYbF4:Ho3+ UCNPs into ZrO2 as the scaffold layer for FA0.4MA0.6PbI3 perovskite solar cells. This design enabled the dual-functional effects, that is, the harvesting of NIR light and its conversion to visible light and the reduction of the electron–hole recombination rate. The effect of different amounts of NaYbF4:Ho3+ UCNPs on the device performance was investigated in detail. The best-performance devices based on optimized addition of UCNPs (40 wt%) could achieve a power conversion efficiency as high as 14.32%, an increase of 28.8% compared with conventional ZrO2 nanoparticle-based PSCs (11.12%). The design of the synergetic operation of UCNPs and ZrO2 in the mesoporous structure of PSCs enhanced the photocurrent and photovoltage. The results offered the flexibility for the device architecture and broaden the solar spectral use of UCNP-based devices.

Three novel zero-dimensional quaternary chalcohalides, Ba4Ge3S9Cl2, Ba4Si3Se9Cl2 and Ba4Ge3Se9Cl2, which crystallize in the polar noncentrosymmetric space group P63 (no. 173), have been rationally synthesized by a tailored approach on the basis of unique [M3Q9]6- (M = Ge, Q = S; M = Ge/Si, Q = Se) units with Ba2+ cations and Cl- anions occupying the interspaces. The [M3Q9]6- units which consist of three Q-corner-sharing [MQ4]4- tetrahedra, are arranged along the 63 screw axis. Remarkably, Ba4Ge3S9Cl2 exhibits a strong powder second harmonic generation (SHG) response that is 2.4 times that of benchmark AgGaS2 at a laser radiation of 2.05 μm in the same particle size range of 46-74 μm. Furthermore, theoretical studies based on the density functional theory helped to gain insight into the origin of the SHG.

Fluorescent zinc-based metal–organic frameworks (Zn-MOFs) were synthesized via the solvothermal method. The materials were characterized by scanning electron microscopy, Brunauer–Emmett–Teller analysis, X-ray diffraction, Fourier transform infrared spectroscopy, fluorescence spectroscopy and fluorescence photography. The results illustrated that the synthesized Zn-MOFs were highly porous with a maximum surface area of 5755 m2 g−1. These MOFs had excellent fluorescence properties, which could be efficiently quenched by trace amounts of hydrogen sulfide (H2S). The experimental results indicated that Zn-MOFs were responsive to H2S at the nmol mL−1 level, which is advantageous for fluorescent Zn-MOF-based sensing materials. The synthesized Zn-MOFs also displayed high adsorption abilities toward H2S. It was illustrated that adsorption played an important role in the preconcentration of H2S, which can further increase the fluorescence quenching efficiency and improve the sensitivity for H2S. Under optimized conditions, this Zn-MOF probe exhibited rapid response, excellent selectivity and sensitivity in detection of H2S. The decrease in FL intensity was linearly related to the H2S concentration between 0.094 μmol mL−1 and 18 μmol mL−1. The developed strategy was applied to real natural gas well samples. These results indicated that Zn-MOF is a usable functional material for H2S detection in natural gas, and potentially useful in monitoring natural gas quality and removing H2S.

The effects of dietary krill oil on neurocognitive functions and proteomic changes in brain tissues of d-galactose-induced aging mice were evaluated. Dietary krill oil enhanced the neurocognitive functions of aging mice with a significant (P < 0.05) decrease in escape latency and an increase in the number of times of crossing over the hidden platform during the Morris water maze test. Krill oil was also found to protect against oxidative damage, lipid peroxidation and neurodegenerative diseases. Oxidative stress biomarkers of aging mice administered with krill oil showed significant (P < 0.05) improvement with an increase in serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) levels; there were insignificant changes in the serum malondialdehyde (MDA) level. In terms of proteomic changes, krill oil resulted in upregulation of the Celsr3 and Ppp1r1b gene expression, which contribute to brain development, learning and memory behavior processes. In particular, the Ppp1r1b gene is associated with the inhibition of dopamine releases, which decreases the motivation for learning.

Two classes of rare-earth-organic-containing Waugh-type manganomolybdates (NH4)8{[RE(Hina)(ina)(H2O)2][MnIVMo9O32]}2·12H2O [RE = La3+ (1), Pr3+ (2), Nd3+ (3)] and (NH4)3[RE(Hina)2(H2O)6][MnIVMo9O32]·7H2O [RE = Sm3+ (4), Eu3+ (5), Gd3+ (6), Tb3+ (7), Dy3+ (8), Ho3+ (9), Er3+ (10), Tm3+ (11), Yb3+ (12), Y3+ (13)] (Hina = isonicotinic acid) were prepared by means of a step-by-step synthetic strategy and further characterized by IR spectroscopy, elemental analyses, UV-visible spectroscopy and single-crystal X-ray diffraction. X-ray diffraction indicates that 1–3 consist of an organic–inorganic hybrid dimeric {[RE(Hina)(ina)(H2O)2][MnIVMo9O32]}28− core constituted by two [MnMo9O32]6− units linked via a dinuclear {[RE(Hina)(ina)(H2O)2]2}4+ cation whereas 4–13 are composed of an organic–inorganic hybrid [RE(Hina)2(H2O)6]3+ fragment and one [MnMo9O32]6− polyoxoanion. It should be pointed out that the nature of RE cations controls these two structure types. As far as we know, 1–13 represent the first examples of Waugh-type manganomolybdates including rare-earth-organic subunits so far. Furthermore, their photocatalytic activities for the degradation of azophloxine were probed in aqueous medium and 3 and 8 as representatives were systematically investigated involving the influence of the optimal pH, catalyst dosage and the doping amount of VK-TA18 nanometer titanium dioxide on the photocatalytic activities. The solid-state photoluminescence properties and lifetime decay behaviors of 3, 4 and 5 in UV-visible or near-infrared regions were also examined at ambient temperature.

Non-noble metal electrocatalysts have recently received increasing attention for the hydrogen evolution reaction (HER) in acidic electrolytes. However, in alkaline electrolyzers, the slow kinetics of water splitting leads to their poor HER activities. Here, we demonstrate the synthesis of novel hierarchical nanotubes of CoS/MoS2 and Co3S4/MoS2/Ni2P which exhibit prominent and durable HER capabilities in alkaline solution. Particularly, the Co3S4/MoS2/Ni2P nanotubes present an onset overpotential of 60 mV, a Tafel slope of 98 mV dec−1, and a high exchange current density of 0.21 mA cm−2, which are superior to those exhibited by many noble-metal-free electrocatalysts. The enhanced HER properties of the hybrid nanotubes could be related to their open hollow structure, large surface area and active site number, as well as the synergetic cooperation between different components. The results reported here may provide new inspirations for the construction of advanced nanostructures for promising catalytic applications.

A noncentrosymmetric structure is a prerequisite of many important properties, such as ferroelectric, piezoelectric and nonlinear optical properties. The design synthesis of a noncentrosymmetric compound is highly desired but it is a great challenge. Herein, two new quaternary selenides, Ba8Ga2Sn7Se18, 1 and Ba10Ga2Sn9Se22, 2, have been discovered by solid-state reactions. Compound 1 crystallizes in the centrosymmetric space group Pnma (no. 62) with a = 12.466 (9) A, b = 9.358 (6) A, c = 18.14 (2) A, V = 2116 (3) A3, Z = 2; and 2 crystallizes in the noncentrosymmetric space group Cmc21 (no. 36) with a = 9.384 (2) A, b = 44.834 (6) A, c = 12.416 (2) A, V = 5224 (2) A3, Z = 4. The major motif of both 1 and 2 is the [Ga2Sn7Se18]∞16− ladder chain built by alternately jointed GaSe4 tetrahedra and SnSe4 tetragonal pyramids, and to each of these polyhedra, an accessory (SnSe3 pyramid or Sn2Se4 dimer) is attached. Interestingly, the noncentrosymmetric structure of 2 is the combination of centrosymmetric 1 and the imbedded isolated dimeric [Sn2Se4] with a C2v polar symmetry that separates every two such ladder chains. 1 and 2 directly illustrate that a simple combination reaction can drive the centrosymmetric to noncentrosymmetric structural transformation.

Ferritin is a bionanomaterial that is widely applied in magnetic resonance imaging, drug delivery systems, biocompatible fluorescence, neutron-capture therapy and electrochemical markers. Ferritin also has great potential for use in environmental detection and heavy metal removal due to its hollow cage sequestration and maintenance of iron in a nontoxic and bio-available form. In this study, the heavy metal binding activity of ferritin from Apostichopus japonicus (AjFER) was elucidated using scanning electron microscopy (SEM). It was observed that ferritin aggregation morphology changed dramatically upon exposure to five metals. The reaction systems formed ferritin-Cd, ferritin-As, ferritin-Hg, ferritin-Pb, and ferritin-Cr aggregations. The aggregations of horse spleen ferritin (HSF) and AjFER are relatively unified rules. The enrichment capacity of ferritin was further analyzed using Inductively Coupled Plasma Mass spectrometry. The contents of Cd2+, Hg2+, Cr3+, Pb2+, and As3+ enriched by recombinant AjFER were higher than that for the standard HSF in ordinary groups. Moreover, the concentration levels of enriched heavy metal ions in groups treated with phosphate were higher than those in ordinary dialysis control AjFER groups. The conformation stability of AjFER binding to different heavy metal ions was determined using Circular Dichroism (CD) spectroscopy, which revealed that the second structure of Mn+-ferritin has relative stability. The affinity of ferritin for metal ions was determined using Isothermal Titration Calorimetry (ITC), and the order of binding constant was Pb-Fer > Hg-Fer > Cd-Fer > As-Fer > Cr-Fer. The ion channel was measured using site-directed mutagenesis, which revealed that heavy metal ions primarily enter the protein cage via a three-fold channel and that the ferroxidase center may be one of the key sites for metal ion diffusion into the interior of the protein shell.

A variety of Ce3+ and Tb3+ doped Ba3P4O13 phosphors were synthesized via the solid state reaction method. Their photoluminescence properties, decay lifetime, thermal stability and luminous efficiency were investigated. The possible energy transfer mechanism was proposed based on the experimental results and detailed luminescence spectra and decay curves of the phosphors. The critical distance between Ce3+ and Tb3+ was calculated by both the spectral overlap method and the concentration quenching method. The energy transfer mechanism from Ce3+ to Tb3+ is determined to be dipole–quadrupole interaction. Furthermore, Ba3P4O13:Ce3+,Tb3+ exhibits relatively excellent thermal stability and its intensity remains 92.7% of the initial intensity at 150 °C.

Correction for ‘Designed synthesis of unique ZnS@CdS@Cd0.5Zn0.5S-MoS2 hollow nanospheres for efficient visible-light-driven H2 evolution’ by Bowen Sun et al., CrystEngComm, 2020, 22, 2743–2755, DOI: 10.1039/D0CE00064G.

We present a 200 nm in-diameter single-bead sensor for the detection of single, unlabeled DNA molecules in solution using fluorescence resonance energy transfer technology. DNA-bound Alexa 488 and Crimson 625 loaded on commercial beads served as the donor and acceptor, respectively. Binding of the target DNA to the single bead sensor induces G-quadruplex stretching, resulting in a decrease in fluorescence energy transfer. G-rich telomere sequences formed a G-quadruplex structure in the presence of ZnTCPP, as demonstrated by the detection of two strong donor and acceptor signals. The sensitivity of the sensor was 1 fM. Under optimized conditions using a polydimethylsiloxane microfluidic device, we measured the number of sensor beads by direct counting. By controlling the flow rate via the probe volume, one sensing experiment can be completed in 5 minutes. Based on these results, we propose a new parameter-dependability (RS)-as a quantitative measure to judge the quality of a bio-sensor. This parameter is based on the ratio of the sensor and sensing sample fluorescence signals. This parameter can range from 0.1 to 100, where a value of 10 represents an optimized bio-sensor.

A novel garnet phosphor, Ca2LuHf2(AlO4)3:Ce3+ (CLHA:Ce3+), was successfully designed and synthesized using a solid-state method. Its crystal structure, band structure and photoluminescence properties were investigated in detail. Under n-UV excitation, CLHA:Ce3+ exhibited cyan to blue-green emission depending on the Ce3+ concentration. The QE of the optimal sample was 50.3%. The concentration quenching mechanism of the Ce3+ emission was dominated by dipole–dipole interactions. A novel method to obtain white light was developed by combining the CLHA:Ce3+ phosphor with a CaAlSiN3:Eu2+ red phosphor. Both the emission intensity and thermal stability of CLHA:Ce3+ were found to be superior to those of the commercial (Sr,Ba)2SiO4:Eu2+ phosphor. All of the results indicate the CLHA:Ce3+ phosphor to be a promising candidate for application in white LEDs.

Enhancing the afterglow intensity and prolonging the persistence time, stimulates the applications of long persistent phosphors. However, current methods to improve the luminescent properties of persistent phosphors are invariably complicated. In this work, we demonstrate a simple but effective strategy to manipulate and expand the color of persistent luminescence, through the radiative energy transfer from CaAl2O4:Eu2+,Nd3+ (CA) to Y3Al5O12:Ce3+ (YAG). It is significant to observe that in the CA/YAG composites, the afterglow intensity can be enhanced ∼2.7-fold and the persistence time can be prolonged ∼2.8-fold in comparison with the widely used CA. A white light persistent luminescent composite (B : Y = 10 : 5) with a decay time of 45 h is obtained. Investigations into the mechanism indicate that the great enhancement of the intensity and persistence time of the long persistent luminescence is directly driven by photopic luminous efficiency and the photo-releasing of energy stored in deep traps. Moreover, the persistent luminescence color of the composites can be tuned from blue to yellow through adjusting the YAG content. In addition, the potential and universality of this color manipulation approach are validated. These results will be greatly beneficial for the applications of long persistent phosphors.

A series of novel red-emitting phosphors Mg3−xN2:xEu2+ (0 ≤ x ≤ 0.08) were successfully synthesized by solid-state reactions at low temperature. The grains of the resulting phosphors showed good dispersibility with diameters of about 14–20 μm; some needle-like crystals gradually increased in length and thickness as the sintering time increased. The excitation spectra of the Mg3N2:Eu2+ phosphors showed strong excitation in the range 250–450 nm, with a dominant excitation peak around 428 nm. At excitation wavelengths

A novel hierarchically structured HKUST-1 has been synthesized under hydrothermal synthesis conditions using a mixed ligand strategy, in which benzene-1,3,5-tricarboxylic acid was partially replaced by benzoic acid. The formation of the crystalline HKUST-1 material containing mesoporosity was characterized by a complementary combination of X-ray powder diffraction, Fourier transform infrared spectroscopy, N2 adsorption–desorption isotherms, scanning electron microscopy, transmission electron microscopy and thermogravimetric analysis. These analyses indicated that incorporation of a certain amount of benzoic acid in the crystal lattice of HKUST-1 preserved its crystal structure. The benzoic acid ligand could be seen as “defect” sites that two carboxylate groups of one linker molecule are missing, leading to a distorted paddle-wheel unit, which induced the formation of an intra-crystalline mesoporous structure in HKUST-1. The hierarchically structured HKUST-1 combines the dual merits of two different pore structures, enabling it has maximum structural function in a limited space due to the enhanced diffusion through mesoporous channels. The presented method opens the door for the preparation of a variety of hierarchically structured MOFs.

The nonlinear optical (NLO) susceptibility and laser induced damage threshold (LIDT) of a material are two inversely correlated indicators of the NLO performance. Here two new NLO active indium substituted chalcohalides, Ba6Cs2InxGa10−xSe20Cl4 (x = 2, 1; x = 1, 2) possessing a T1–T2 supertetrahedron anionic framework structure, have been successfully synthesized by solid-state reactions. Unlike the transition metal, the indium substitutes gallium at both T1 and T2 sites according to a series of single crystal diffraction data. Property measurements on the polycrystalline samples reveal that such a substitution improves the crystallinity and LIDT without adversely affecting the SHG power if compared with the transition metal substitution. Consequently, the title compounds show an optimal NLO performance among the compounds of this type of structure obtained so far. Introduction to the international collaboration The collaboration between Fujian Institute of Research on the Structure of Matter (FJIRSM: Ling Chen) and Paul Scherrer Institute (PSI: Meitian Wang) started back in 1993 when they were master's degree students in the Chemistry Department, Beijing Normal University, and jointly worked on the project of rare earth metal iodides with low valence states focusing on solid-state syntheses, crystal structures and theoretical analyses (L. Chen, M. T. Wang, S. H. Wang, Synthesis and structure of new iodides Cs4EuI6 and Rb4EuI6, J. Alloys Comp. 1997, 256, 112–114.). Since then, the cooperation continued when they were scattered in Alberta University in Canada, and Iowa State University in USA. No matter where they were, their cooperation has never been interrupted. This work is their second joint publication.