Preparation and Application of a Novel S-Scheme Nanoheterojunction Photocatalyst (LaNi0.6Fe0.4O3/g-C3N4).

Rapid recombination of photogenerated electrons and holes affects the performance of a semiconductor device and limits the efficiency of photocatalytic water splitting for hydrogen production. The use of an S-scheme nanoscale heterojunction catalyst for the separation of photogenerated charge carriers is a feasible approach to achieve high-efficiency photocatalytic hydrogen evolution. Therefore, we synthesized a three-dimensional S-scheme nanoscale heterojunction catalyst (LaNi0.6Fe0.4O3/g-C3N4) and investigated its activity in photocatalytic water splitting. An analysis of the band structure (XPS, UPS, and Mott-Schottky) indicated effective interfacial charge transfer in an S-scheme nanoscale heterojunction composed of two n-type semiconductors. X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) spectroscopy confirmed that the light-induced charge transfer followed the S-scheme mechanism. Based on the capture test (EPR) of •OH free radicals, it can be seen that the enhanced activity is attributed to the S-scheme carrier migration mechanism in heterojunction, which promotes the rapid adsorption of H+ by the abundant amino sites in g-C3N4, thus effectively generating H2. The 2D/2D LaNi0.6Fe0.4O3/g-C3N4 heterojunction has a good interface and produces a built-in electric field, improving the separation of e- and h+ while increasing the oxygen vacancy. The synergistic effect of the heterostructure and oxygen vacancy makes the photocatalyst significantly better than LaNi0.6Fe0.4O3 and g-C3N4 in visible light. The hydrogen evolution rate of the composite catalyst (LaNi0.6Fe0.4O3/g-C3N4-70 wt %) was 34.50 mmol·h-1·g-1, which was 40.6 times and 9.2 times higher than that of the catalysts (LaNiO3 and g-C3N4), respectively. After 25 h of cyclic testing, the catalyst (LaNi0.6Fe0.4O3/g-C3N4-70 wt %) composite material still exhibited excellent hydrogen evolution performance and photostability. It was confirmed that the synergistic effect between abundant active sites, enriched oxygen vacancies, and 2D/2D heterojunctions improved the photoinduced carrier separation and the light absorption efficiency of visible light. This study opens up new possibilities for the logical design of efficient photodecomposition using 2D/2D heterojunctions combined with oxygen vacancies.

Fe-Doped Metal Complex (LaCo0.9Fe0.1O3) and g-C3N4 Formed a Nanoheterojunction for the Photocatalytic Decomposition of Water.

Photocatalytic water decomposition provides an environmentally friendly method of hydrogen production similar to "photosynthesis", while current research aims to develop affordable yet efficient photocatalysts. Oxygen vacancy is one of the most significant defects in metal oxide semiconductors, including perovskite, which substantially influences the semiconductor material's efficiency. To enhance the oxygen vacancy in the perovskite, we worked on doping Fe. A perovskite oxide nanostructure of LaCoxFe1-xO3 (x = 0.2, 0.4, 0.6, 0.8, and 0.9) was prepared by the sol-gel method, and a series of LaCoxFe1-xO3 (x = 0.2, 0.4, 0.6, 0.8, and 0.9)/g-C3N4 nanoheterojunction photocatalysts were synthesized using mechanical mixing and solvothermal methods for LaCoxFe1-xO3 (x = 0.2, 0.4, 0.6, 0.8, and 0.9). Fe was successfully doped into the perovskite (LaCoO3), and the formation of an oxygen vacancy was verified by various detection methods. In our photocatalytic water decomposition experiments, we observed that LaCo0.9Fe0.1O3 demonstrated a significant increase in its maximum hydrogen release rate, reaching 5249.21 µmol h-1 g-1, which was remarkably 17.60 times higher than that of LaCoO3-undoped Fe. Similarly, we also explored the photocatalytic activity of the nanoheterojunction complex LaCo0.9Fe0.1O3/g-C3N4, and it exhibited pronounced performance with an average hydrogen production of 7472.67 µmol h-1 g-1, which was 25.05 times that of LaCoO3. We confirmed that the oxygen vacancy plays a crucial role in photocatalysis.

La2CoO4+δ perovskite-mediated peroxymonosulfate activation for the efficient degradation of bisphenol A.

Sulfate radical-based technology has been considered as an efficient technology to remove pharmaceuticals and personal care products (PPCPs) with heterogeneous metal-mediated catalysts for the activation of peroxymonosulfate (PMS). In this study, La2CoO4+δ perovskite with Ruddlesden-Popper type structure was synthesised by the sol-gel method, which was employed in PMS activation. Different characteriazation technologies were applied for the characterization of La2CoO4+δ , such as SEM-EDX, XRD, and XPS technologies. A common organic compound, bisphenol A (BPA), is used as a target contaminant, and the effect impactors were fully investigated and explained. The results showed that when the dosage of La2CoO4+δ was 0.5 g L-1 and the concentration of PMS was 1.0 mM in neutral pH solution, about 91.1% degradation efficiency was achieved within 25 minutes. Quenching experiments were introduced in the system to verify the catalytic mechanism of PMS for the BPA degradation, proving the existence of superoxide, hydroxyl radicals and sulfate radicals, which are responsible for the catalytic degradation of BPA. Moreover, the reusability and stability of the catalyst were also conducted which showed good stability during the reaction. This work would improve the applications of A2BO4-type perovskites for activating PMS to degrade BPA.

Enhanced Degradation of Levofloxacin through Visible-Light-Driven Peroxymonosulfate Activation over CuInS2/g-C3N4 Heterojunctions.

In this work, the heterojunctions of CuInS2 embedded in the g-C3N4 materials (xCuInS2/g-C3N4, abbreviated as xCIS/GCN) was successfully prepared for peroxymonosulfate (PMS) activation under visible light. The catalysts are characterized by different techniques, such as XRD, FTIR, SEM, TEM, and UV-vis. The unique heterojunction composites can suppress the recombination of photogenerated pairs. The catalytic results showed that the 3CIS/GCN exhibited excellent catalytic levofloxacin (LVF) degradation efficiency, while more than 98.9% of LVF was removed in 60 min over a wide pH range. SO4•-, O2•-, OH•, and 1O2 were verified as the main reactive species for LVF degradation via the quenching experiments and electron paramagnetic resonance technology (EPR). The synergetic effect of xCIS/GCN, PMS, and visible light irradiation was discussed. The possible LVF degradation pathway was proposed through byproducts analysis (LC-MS). Moreover, the 3CIS/GCN/vis-PMS system has very low metal leaching. Owing to xCIS/GCN having good properties for PMS activation, it has potential applications for LVF or other hazardous pollutants degradation.

Z-scheme LaCoO3/C3N5 for efficient full-spectrum light-simulated solar photocatalytic hydrogen generation.

The development of photocatalysts with high activity and low cost is still a major challenge. Since its synthesis in 2019, C3N5 has become an emerging photocatalytic material and has been widely studied. In this work, we report on the preparation of LaCoO3/C3N5 nanosheets and the use of LaCoO3 instead of precious metals to improve photocatalytic hydrogen production activity. First, LaCoO3 was successfully prepared by the sol-gel method and then a series of high-efficiency Z-type LaCoO3/C3N5 heterojunction photocatalysts were synthesized by the solvothermal method. Various characterization techniques (XRD, FT-IR, SEM, TEM, EDS, XPS, UV-Vis DRS, BET, ESR) confirmed the formation between LaCoO3 nanoparticles and C3N5 nanosheet heterostructures and interface interactions. In the photocatalytic water split test, 50 wt% LaCoO3/C3N5 showed the highest photocatalytic activity of 956.11 µmol h-1 g-1, which was 3.21 and 1.59 times that of LaCoO3 and C3N5, respectively. This work not only designs an inexpensive and efficient LaCoO3/C3N5 photocatalytic system for water splitting or other photocatalytic applications, but also provides ideas for constructing new material photocatalytic systems.

A Multistimuli Responsive Crystalline Cd(II)-Viologen Coordination Polymer with Single-Crystal-Single-Crystal Transformation.

It is necessary to develop stable and fast multistimuli responsive materials due to the growing demand in our daily life. In this work, a new viologen-based Cd-complex (1) exhibits multiple thermochromic and photochromic behaviors through 10 states with 7 colors. For example, it responds to both Cu Kα/Mo Kα X-ray sources and UV dual light quickly with a color change from colorless to dark blue (1X) (Cu Kα/Mo Kα X-ray sources) and cyan (1-UV) (UV light), respectively. Interestingly, it exhibits a three-step coloration phenomenon when heated, which is unprecedented in viologen compounds. Crystal 1 undergoes a color change to pink, blue, and brown under 130, 180, and 240 °C, respectively. In addition, upon fumigation, both 1P and 1Q undergo a decoloration process to colorless (1K) and yellow (1T), respectively. Four more states (1P, 1K, 1T, and 1O) obtained via dehydration-hydration treatment are all photochromic. More importantly, via single-crystal-single-crystal transformation (SC-SC), the photochromic and thermochromic behaviors of 1 were investigated from the molecular level, which is also rather rare for thermochromic species. The detailed electron donor and the pathways for electron transfer were clearly given according to the results of crystal structure. The colorful states upon external stimuli may be attributed to the multiple pathways for electron transfer.

The high photocatalytic efficiency and stability of LaNiO3/g-C3N4 heterojunction nanocomposites for photocatalytic water splitting to hydrogen.

A binary direct Z-scheme LaNiO3/g-C3N4 nanocomposite photocatalyst consisted with LaNiO3 nanoparticles and g-C3N4 nanosheets was successfully synthesized by means of mechanical mixing and solvothermal methods in order to improve the photocatalytic water splitting activity. The as-prepared materials were characterized by powder X-ray diffraction (XRD), Scanning Electron microscope (SEM), Transmission Electron microscope (TEM), X-ray photoelectron spectroscope (XPS), Fourier Transform Infrared Spectroscopy (FT-IR) and N2 adsorption-desorption experiments, respectively, demonstrating the formation of interfacial interaction and heterogeneous structure in LaNiO3/g-C3N4 nanocomposites. Under UV-light irradiation, the LaNiO3/g-C3N4 samples which without the addition of any noble metal as co-catalyst behaved enhanced photocatalytic water splitting activity compared with pure LaNiO3 and g-C3N4, owing to the Z-scheme charge carrier transfer pathway. Especially, the LaNiO3/70%g-C3N4 nanocomposite reach an optimal yield of up to 3392.50 µmol g-1 in 5 h and held a maximum H2 evolution rate of 678.5 µmol h-1 g-1 that was 5 times higher than that of pure LaNiO3.

Z-Scheme LaCoO3/g-C3N4 for Efficient Full-Spectrum Light-Simulated Solar Photocatalytic Hydrogen Generation.

Photocatalytic decomposition of water is the most attractive method for the sustainable production of hydrogen, but the development of a highly active and low-cost catalyst remains a major challenge. Here, we report the preparation of LaCoO3/g-C3N4 nanosheets and the utilization of LaCoO3 instead of noble metals to improve the photocatalytic activity for the production of hydrogen. First, LaCoO3 was successfully prepared by the sol-gel method, and then a series of highly efficient Z-scheme LaCoO3/g-C3N4 heterojunction photocatalysts were synthesized by the solvothermal method. Various characterization techniques (X-ray diffraction (XRD), Fourier transform infrared (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy (DRS), photoluminescence (PL), transient photocurrent response test, electron paramagnetic resonance (EPR)) confirm that the heterostructure and interfacial interaction had been formed between LaCoO3 nanoparticles and g-C3N4 nanosheets. In the photocatalytic water splitting test, LaCoO3/g-C3N4-20 wt % exhibited the highest photocatalytic activity of 1046.15 µmol h-1 g-1, which is 3.5 and 1.4 times higher than those of LaCoO3 and g-C3N4, respectively. This work leads to an inexpensive and efficient LaCoO3/g-C3N4 photocatalysis system for water splitting or other photocatalytic applications.

Cocrystallization with syringic acid presents a new opportunity for effectively reducing the hepatotoxicity of isoniazid.

Objective: With the aim of surmounting the severe hepatotoxicity induced by antituberculosis drug isoniazid (INH), a novel cocrystal of INH with hepatoprotective nutraceutical syringic acid (SYA), namely INH-SYA, was designed and prepared through cocrystallization strategy, which is an intriguing attempt to reduce the toxic side effects of INH.Significance: The study not only provides new thinking for inhibiting toxic side effects of drugs through cocrystallization strategy, but also opens a new pathway for the application of nutraceuticals in the pharmacy.Methods: INH and SYA were successfully crystallized into the same crystal lattice through combining volatilization with solvent assisted methods. The resulting cocrystal was structurally characterized by single crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD), and differential scanning calorimetry (DSC).Results: The SCXRD analysis for the present cocrystal revealed that it has a 1:1 ratio of INH to SYA with two molecules INH homodimers and two SYA molecules, in which they are arranged alternately linked by hydrogen bonds to form a six molecules ring structure (R66(40)) in crystal. The systematic evaluation of the in vitro/in vivo suggested that, owing to the formation of cocrystal, the dissolution efficiency of SYA was increased 5.85-fold compared with that of coarse SYA, and the oral bioavailability of the cocrystal in rats was enhanced by 3.66 times. As a result, the present INH-SYA cocrystal almost removed INH induced serious hepatotoxicity, which was further demonstrated by the hepatotoxicity studies in rats.Conclusion: INH-SYA cocrystal could effectively reduce the hepatotoxicity of INH.

Brønsted acid/visible-light-promoted Markovnikov hydroamination of vinylarenes with arylamines.

A Brønsted acid/visible-light-promoted Markovnikov hydroamination of vinylarenes with arylamines in the presence of TPT and CF3CO2H has been developed. This transformation provides a green approach to alpha-amino-substituted arylalkanes under metal-free conditions.

Real-time analysis of self-assembled nucleobases by Venturi easy ambient sonic-spray ionization mass spectrometry.

In this study, the real-time analysis of self-assembled nucleobases was employed by Venturi easy ambient sonic-spray ionization mass spectrometry (V-EASI-MS). With the analysis of three nucleobases including 6-methyluracil (6MU), uracil (U) and thymine (T) as examples, different orders of clusters centered with different metal ions were recorded in both positive and negative modes. Compared with the results obtained by traditional electrospray ionization mass spectrometry (ESI-MS) under the same condition, more clusters with high orders, such as [6MU7+Na](+), [6MU15+2NH4](2+), [6MU10+Na](+), [T7+Na](+), and [T15+2NH4](2+) were detected by V-EASI-MS, which demonstrated the soft ionization ability of V-EASI for studying the non-covalent interaction in a self-assembly process. Furthermore, with the injection of K(+) to the system by a syringe pumping, the real-time monitoring of the formation of nucleobases clusters was achieved by the direct extraction of samples from the system under the Venturi effect. Therefore, the effect of cations on the formation of clusters during self-assembly of nucleobases was demonstrated, which was in accordance with the reports. Free of high voltage, heating or radiation during the ionization, this technique is much soft and suitable for obtaining the real-time information of the self-assembly system, which also makes it quite convenient for extraction samples from the reaction system. This "easy and soft" ionization technique has provided a potential pathway for monitoring and controlling the self-assembly processes.

Characterization of rhodamine self-assembled films using desorption electrospray ionization mass spectrometry.

Growth process information and molecular structure identification are very important for characterization of self-assembled films. Here, we explore the possible application of desorption electrospray ionization mass spectrometry (DESI-MS) that provides the assembled information of rhodamine B (Rh B) and rhodamine 123 (Rh 123) films. With the help of lab-made DESI source, two characteristic ions [Rh B](+) and [Rh 123](+) are observed directly in the open environment. To evaluate the reliability of this technique, a comparative study of ultraviolet-visible (UV-vis) spectroscopy and our method is carried out, and the result shows good correlation. According to the signal intensity of characteristic ions, the layer-by-layer adsorption process of dyes can be monitored, and the thicknesses of multilayer films can also be comparatively determined. Combining the high sensitivity, selectivity, and speed of mass spectrometry, the selective adsorption of similar structure molecules under different pH is recognized easily from extracted ion chronograms. The variation trend of dyes signalling intensity with concentration of polyelectrolyte is studied as well, which reflects the effect of surface charge on dyes deposition. Additionally, the desorption area, surface morphology, and thicknesses of multilayer films are investigated using fluorescence microscope, scanning electron microscope (SEM), and atomic force microscopy (AFM), respectively. Because the desorption area was approximately as small as 2 mm(2), the distribution situation of organic dyes in an arbitrary position could be gained rapidly, which means DESI-MS has advantages on in situ analysis.

Novel application of Ag nanoclusters in fluorescent imaging of human serum proteins after native polyacrylamide gel electrophoresis (PAGE).

We have developed a novel application for DNA oligonucleotide-stabilized Ag nanoclusters in fluorescent imaging of human serum proteins after native polyacrylamide gel electrophoresis (PAGE). Oligonucleotide-stabilized Ag nanoclusters were used as fluorescent probes for direct detection of proteins after native PAGE. Some relatively low-abundance proteins, such as α-1-antichymotrypsin (ACT) and α-2-glycoprotein 1, zinc (ZAG) were easily detected by oligonucleotide-stabilized Ag nanocluster-based fluorescent imaging and identified by MS and MS/MS techniques, without the need of expensive antibodies or tedious immunoassay procedures. The pH condition for the oligonucleotide-stabilized Ag nanocluster solution was optimized and the possible mechanism of interaction between proteins and DNA oligonucleotide-stabilized Ag nanoclusters was analyzed. As a novel fluorescent detection method it is simple, fast, nontoxic and sensitive, and it shows great analytical potential in proteome research and in biochemistry.

Carbon nanotubes-assisted polyacrylamide gel electrophoresis for enhanced separation of human serum proteins and application in liverish diagnosis.

The application of pore-gradient polyacrylamide gel electrophoresis (PG-PAGE) incorporated with carbon nanotube modified by Triton X-100 and carboxylation so as to improve the separation of human serum proteins is reported. The novel PG-PAGE was made by adding water-soluble single-walled carbon nanotubes (CNTs) when preparing the polyacrylamide gel. Significant improvements in separation of complement C3 protein and haptoglobin (Hp) in human serum were achieved. It was estimated that the interactions between the hydrophilic groups on the proteins and the surface of the CNTs result in different adsorption kinetics of complement C3 and Hp subtype on the nanoparticles incorporated in the gel, thus enhancing the separation of the two proteins in serum. This new CNT matrix-assisted PG-PAGE method for enhanced separation of complement C3 and Hp in human serum was successfully applied to distinguish the samples from liverish patients and healthy people.

[Mu3-cis-N-(2-aminoethyl)-N'-(2-carboxylatophenyl)oxamidato(3-)]bis(2,2'-diamino-4,4'-bi-1,3-thiazole)tetracopper(II) bis(2,4,6-trinitrophenolate).

The title complex, [Cu(4)(C(11)H(10)N(3)O(4))(2)(C(6)H(6)N(4)S(2))(2)](C(6)H(2)N(3)O(7))(2), consists of a circular tetracopper(II) cation with an embedded inversion centre and two uncoordinated picrate (2,4,6-trinitrophenolate) anions. The Cu(II) cations at the inner sites of N-(2-aminoethyl)-N'-(2-carboxylatophenyl)oxamidate(3-) (oxbe) have square-planar environments and those at the outer sites are in square-pyramidal geometries. The separations of pairs of Cu(II) cations bridged by cis-oxamide and carboxylate groups are 5.2217 (5) and 5.2871 (5) A, respectively. The tetracopper(II) cations and picrate anions are connected by N-H...O hydrogen bonds into a two-dimensional network parallel to the (010) plane, and these two-dimensional networks are assembled by two types of pi-pi stacking interactions into a three-dimensional supramolecular structure.

Poly[bis-(µ(3)-5-nitro-isophthalato)bis-(1,10-phenanthroline)dimanganese(II)].

The title complex, [Mn(2)(C(8)H(3)NO(6))(2)(C(12)H(8)N(2))(2)](n), was synthesized under hydro-thermal conditions. The structure contains two independent Mn(II) atoms, each coordinated in a distorted octa-hedral MnN(2)O(4) geometry. [Mn(2)(phen)(2)] units (phen = 1,10-phenantroline) are bridged by 5-nitro-isophthalate (nip) ligands into ladder-like chains parallel to [100]. Adjacent polymeric chains are linked by C-H⋯O and π-π inter-actions [centroid-to-centroid distance = 3.6369 (12) Å] into a two-dimensional framework parallel to (010).

Metallomicellar catalysis: hydrolysis of phosphate monoester and phosphodiester by Cu(II), Zn(II) complexes of pyridyl ligands in CTAB micellar solution.

The catalytic hydrolysis of bis(p-nitrophenyl) phosphate (BNPP) and p-nitrophenyl phosphate (NPP) by metallomicelles composed of Cu(II) or Zn(II) complexes of bispyridine-containing alkanol ligands in CTAB micellar solution was investigated at 30 degrees C. The experimental results indicate that the complexes with a 1:1 ratio of ligands to metal ions for ligands 1 (1,7-bis(6-hydroxymethyl-2-pyridyl)-2,6-dioxaheptane) and 3 (1,4-bis[(6-hydroxymethyl-2-pyridyl)-2-oxapropyl]benzene) and a 1:2 ratio of ligands to metal ions for ligand 2 (1,14-bis(6-hydroxymethyl-2-pyridyl)-2,13-dioxatetradecane) in CATB micellar solution are the active species for the catalytic hydrolysis of BNPP and NPP, respectively. The ternary complex kinetic model for metallomicellar catalysis was employed to obtain the relative kinetic and thermodynamic parameters, which demonstrated the catalytic mechanism for the hydrolysis of BNPP and NPP by metallomicelles.