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Transition metal phosphides (TMPs) are regarded as highly efficient electrocatalysts due to highly active surface sites, electrical conductivity, and chemical stability, which result from the high electrocatalytic activity of the M-centers and P-sites. Thus, the aim of our work is to obtain highly efficient TMPs electrocatalysts by a facile and controllable strategy. We used N, S-rich Co/Fe bimetallic metal-organic framework as template to prepare ceramic Co/Fe binary phosphides embedded in N, S, O ternary-doped carbon matrix (CoFeP@NSOC). By means of a facile one-step low-temperature pyrolysis-phosphating approach, the optimized ceramic material CoFeP@NSOC-400 showed remarkable bifunctional electrocatalytic performances in an alkaline electrolyte, which only requires 176 and 240 mV overpotentials to achieve 10 mA cm−2 current density for HER and OER, respectively. Furthermore, when CoFeP@NSOC-400 is loaded on the highly conductive nickel foam (NF) for water splitting, it reaches a current density of 10 mA cm−2 at a low cell voltage of 1.62 V, superior to pure NF and other reported metal-phosphide electrocatalysts, at the same time, CoFeP@NSOC-400 shows negligible performance degradation and a relative current loss of only 4.3% for 40000 s continuous operations. These results indicate CoFeP@NSOC derived by MOFs through pyrolysis-phosphating is an ideal electrocatalysts for energy conversion applications.

V/UiO-66-NH2 was prepared by the vanadium oxyacetylacetonate grafted on UiO-66-NH2. The catalytic performance of V/UiO-66-NH2 was investigated for the hydroxylation of benzene to phenol using O2. It can give the high yield of 22.0% for phenol with high selectivity of 98.1% while the UiO-66-NH2 as the catalyst can give the yield of 5.2%. The synergetic effect between the Zr MOF and the V complex was contributed to the high efficiency of the V/UiO-66-NH2 catalyst. Furthermore, the V/ZrO2 catalyst obtained by calcination of V/UiO-66-NH2 under the nitrogen gave the yield of 16.2% with the selectivity of 98.3%, which can be recycled. The catalysts can also be employed for the co-reductant free catalyst, which give the yield of about 5% with high selectivity.

Vanadium-zirconium catalyst was prepared with zirconium tetrachloride and ammonium metavanadate, which were supported on different supports, such as activated carbon, g-C3N4, MWCNTs (multiwall carbon nano tubes), acidified MWCNTs, bentonite, and γ-Al2O3. Various techniques were employed to characterize the catalysts such as X-ray diffraction, X-ray photoelectron spectroscopy, nitrogen adsorption, and Raman spectrum. It was found that Zr4+ and V5+ in the vanadium-zirconium catalyst were dispersed on support in the form of zirconium pyrovanadate. The performance of catalysts on hydroxylation of benzene to phenol with O2 as the oxidant was investigated. The vanadium-zirconium catalyst with different supports showed different catalytic performance and the reason was studied. It was found that the catalytic performance was related to the nature of the supports including the surface area and the composition of the supports. The yield of phenol reached to 8.6% and selectivity reached to about 80% when the activated carbon acted as support. Kinetic study showed that the first step of the consecutive reaction was first order for benzene and the second step was first order for phenol.

The luminescent metal–organic frameworks (LMOFs) have been widely used as sensors for toxic organic compounds or heavy metals due to their functional sites and accessible pores. About this work, a new luminescent metal–organic framework, {[Cd3(L)2(H2O)4]·4H2O}n (1) has been synthesized through the spontaneous self-assembly of V-shaped asymmetrical tricarboxylate ligand (H3L = 2-(4-carboxylphenoxy)terephthalic acid) and Cd(NO3)2·4H2O under hydrothermal condition. Single crystal X-ray diffraction analysis H3L is completely deprotonated and connects Cd(II) to exhibit a 3D microporous structure. Furthermore, the complex shows a strong fluorescence emission, and can act as a potential multifunctional fluorescent probe for detection of nitroaromatic, Fe3+, Cr2O72− and CrO42− anions with high stability, selectivity and sensitivity. Secondly, the complex can effectively sensitize visible-light-emitting Tb3+ ions as an antenna and rapidly remove harmful organic dye Methylene Blue (MB) as an adsorbent. Thus, the multifunctional complex 1 combines optical-sensing, adsorption, and sensitization properties, which is very useful in many potential applications.

Mitochondrial viscosity is related to numerous physiological processes such as solute diffusion, enzyme catalysis, protein folding, translocation, and conformation change. It is significant to evaluate and monitor the mitochondrial viscosity changes in living cells. In this work, we developed a simple chalcone molecular rotor Mito-HCA for specific fluorescence imaging of mitochondrial viscosity changes in living cells. The chalcone molecular rotor Mito-HCA consists of a donor-π-acceptor (D-π-A) chalcone skeleton with a typical twisted intramolecular charge transfer (TICT) feature and a triphenylphosphonium unit for mitochondrial targeting. The fluorescent intensity and fluorescence lifetime of the probe Mito-HCA reveal good sensitivity and high selectivity to solution viscosity. It can be conveniently used for the specific fluorescence imaging of mitochondria and mitochondrial viscosity detection benefit from the simple synthetic procedure, large Stokes shift, high pH stability and low cytotoxicity. The fluorescent intensity and fluorescence lifetime of probe Mito-HCA exhibits good sensitivity to mitochondrial viscosity changes in living cells under osmotic shock, starvation stress and ionophore (monensin) incubation.

An environmentally benign nano CuO catalyzed strategy has been developed for one-pot synthesis of quinazolinone Schiff base derivatives and bis-2,3-dihydroquinazolin-4(1 H )-ones by use of hydrazine hydrate and ethidene diamine as nitrogen source. The antibacterial activity was investigated using minimum inhibitory concentration (MIC) method against four bacterial strains. Tests have shown that these derivatives have potential activity against Streptococcus lactis . The structure–activity relationship of the antibacterial activity evaluation was also explored.

Two series of spiro-oxindole dihydroquinazolinone derivatives have been designed and synthesized using a catalytic amount of nano cerium oxide with excellent product yields by a convenient one-pot process. The synthesized compounds were evaluated for their in vitro antibacterial activity, and compounds 1i–1p showed considerable antibacterial activities to Escherichia coli. Molecular docking of E. coli Biotin Carboxylase (EcBC) enzyme was also performed in order to predict the interactions of the synthesized compounds.

A CuO nanoparticle-catalyzed one-pot process has engineered for the preparation of diverse quinazolinones from the readily available isatoic anhydride, aldehydes and amine or ammonium. For amine substrates the reactions afford 2,3-dihydroquinazolin-4(1 H )-ones in aqueous ethanol promoted by ultrasound irradiation. However, the ammonium substrates undergo intramolecular electron transfer and rearrangement yielding quinazolin-4(3 H )-ones. The catalyst is recyclable four times without loss of substantial activity. Other remarkable features include the wide range of functional group tolerance (46 quinazolinones are synthesized and 9 of them are reported firstly), and providing moderate to excellent yield of the products under mild conditions.