To overcome over-adsorption of Ni, we propose a nitrogen engineering strategy to construct a N-Ni/N-CeO2 heterostructured electrocatalyst, exhibiting a small overpotential of 350 ± 4.5 mV at 1 A cm-2 for the hydrogen evolution reaction.

The electrochemical reconstruction behavior of metal-organic frameworks (MOFs) profoundly affects their catalytic performance, but their effective regulation remains a major challenge. Herein, we propose a facile single-atom-driven strategy to manipulate the surface reconstruction of a gallogen-based MOF, engineering an efficient active structure of ellagic acid and monatomic Cu co-modified bismuth oxycarbonate, achieving organic-inorganic dual-modulation. The reconstructed organic-inorganic hybrid electrocatalyst demonstrates notable performance for CO2 electroreduction to formate with a maximal Faraday efficiency of 99.4% +/- 1.5%. Moreover, throughout the continuous electrocatalysis period of 600 h at 250 mA & centerdot;cm-2, the formate Faraday efficiency always maintains above 95.2% +/- 2.4%. The corresponding charge transfer amount for formate generation reaches 507600 C & centerdot;cm-2, representing one of the best among CO2-to-formate electrocatalysts and setting a record among bismuth-based electrocatalysts. A series of operando and non-operando characterization techniques combined with theoretical calculations reveal that the dual-modulation of monatomic Cu and ellagic acid optimizes the p-band center of Bi sites, thereby enhancing the adsorption of key *OCHO intermediate. This work establishes a molecular enhancement paradigm for engineering high-performance electrocatalysts by harnessing surface reconstruction of MOFs.

While great advances have been achieved in Zn-air batteries, porous cathode catalysts remain crucial and challenging to promote diffusion and boost oxygen reduction reaction (ORR). Herein, an effective strategy has been developed for the synthesis of hollow metal-nitrogen-carbon electrocatalysts to achieve the macro-/meso-/microporous structure. The h-CuNC electrocatalyst exhibits good stability and high ORR activity with a half-wave potential of 0.91 V. Theoretical calculations reveal that CuNC sites can reduce the energy barrier of *OOH adsorption, which is the rate-determining step. Zn-air battery with h-CuNC as the cathode catalyst enables high peak power density of 201 mW cm-2 and good rate performance. Our work demonstrates the concept that hollow mesoporous MNC can significantly improve the catalytic performance by enhancing diffusion.

Norfloxacin (NOR) has raised growing concerns over food safety and environmental sustainability due to its persistence and bioaccumulation. The luminescence turn-on effect induced by NOR offers a promising approach for the development of advanced sensing platform and anticounterfeiting platform. In this work, two novel one-dimensional chain-like lanthanide coordination polymers, Tb-TCDA and Eu-TCDA, were successfully synthesized through a facile one-step hydrothermal approach. Interestingly, Tb-TCDA demonstrates a pronounced luminescence turn-on effect upon reaction with NOR, functioning as a highly selective and sensitive probe for NOR detection, with a detection limit as low as 0.03 μM and a rapid response time (<20 s). The sensing performance is maintained in complicated real-world matrices, including dairy products (milk, eggs), lake water, and tap water. Notably, portable test strips fabricated by immobilizing Tb-TCDA onto filter paper enable on-site visual identification of NOR contamination within minutes, demonstrating excellent practicality. In addition, the stimuli-responsive luminescence turn-on behavior of Tb-TCDA and Eu-TCDA supports their potential application in advanced anticounterfeiting technologies. This work provides a dual-functional platform that integrates luminescence sensing and security features, offering new opportunities for real-time antibiotic monitoring and anticounterfeiting systems.

The trade-off of the Volmer reaction for *H formation and the Heyrovsky/Tafel Reaction for *H desorption is a crucial challenge in alkaline hydrogen evolution reaction (HER). Thus, aside from the conventional construction of bifunctional active sites to accelerate the water dissociation step, the electronic retrimming of each metal site is also non-negligible. Herein, an efficient HER electrocatalyst combining Pt single-atoms and Pt nanoparticles on the etched boron nitride (eBN) coated carbon nanotube (Pt-eBN@CNT) is synthesized, where both the Volmer and Heyrovsky steps are promoted by the synergistic adsorption of the composite active sites and the electron-withdrawing effect of eBN carrier, respectively. The proposed catalyst shows impressive performance in alkaline media with an overpotential of 25.1 ± 1.7 mV at 10 mA cm-2, and a TOF of 17.1 ± 1.3 s-1 at 0.15 V vs RHE under extremely low metal loading of 6 µgPt cm-2 (catalyst loading of 0.77 mg cm-2), significantly better than those for the commercial benchmark Pt/C (44.2 ± 4.1 mV, 0.9 ± 0.1 s-1 at catalyst loading of 0.77 mg cm-2; 156.1 ± 0.6 mV, 1.6 ± 0.1 s-1 at metal loading of 6 µgPt cm-2) under the same conditions. Moreover, a membrane-electrode-assembly (MEA) electrolyzer with Pt-eBN@CNT as the cathodic catalyst exhibits a notable charge transfer amount (stands for a long service life) of 2.0 × 106 C·cm-2 within high-temperature electrocatalysis at 1.0 A·cm-2, significantly higher than those of state-of-the-art Pt-based electrocatalysts. This work demonstrates the important role of active-site combination coupled with carrier effect in optimizing the kinetics of multi-step electrocatalytic reaction.

Cathode reconstruction is equally crucial for water electrolysis, yet it has received less attention than anode. Lattice selenium (Se) doping is an effective strategy to improve hydrogen evolution reaction (HER) of metal‐based electrocatalysts in cathodes, but many fundamental questions concerning the actual role of Se on the active species as well as catalytic kinetics remain to be clarified, especially in those electrocatalytic self‐reconstruction systems. Here, we showcase the accelerated two‐stage structural evolution of Se‐doped cobalt phosphide (Se‐CoP) during alkaline HER by operando X‐ray absorption spectroscopy and powder X‐ray diffraction, combined with high‐resolution transmission electron microscopy (HRTEM) analysis. Further density functional theory (DFT) calculations suggest that the in situ formed dual‐component heterostructure of highly crystalline Co(OH) 2 and robust Co nanoclusters, which are decorated with residual Se, is responsible for the high HER performance. The reconstructed Se‐CoP on carbon cloth delivers a low overpotential of 79 ± 2 mV at 100 mA · cm −2 and achieves an impressive charge transfer amount of 6.3 × 10 5 C cm −2 operating at 500 mA cm −2 , surpassing the reported electrocatalysts constructed by non‐noble metal phosphides. This work provides brand‐new perspectives on the self‐reconstruction perturbed by heteroatoms for well‐designed composite electrocatalysts.

In recent years, foods that contaminated by the antibiotics is a serious threat to human health, so, the on-site visual detection of antibiotics in food is crucial. In this work, two new two-dimensional lanthanide metal- -organic frameworks (2D LnMOFs) are synthesized by mild hydrothermal method and detailly characterized by single crystal structure analysis, photophysics, thermal gravimetric analysis (TGA), powder X-ray diffraction (PXRD), FT-IR spectra. Results show the two LnMOFs has high thermo-stability, strong acid and alkaline resistance. Further studies reveal that TbMOF is a highly sensitive and selective fluorescent probe for the antibiotics of enrofloxacin (Enr) and ciprofloxacin (Cip), with a very short response time of 15 s. The limits of detection (LODs) for Enr and Cip are very low values of 190 and 70 nM, respectively, based on the method of 3 sigma/K, which is lower than the national food safety standard (GB 31650-2019). In addition, portable test paper based on TbMOF is fabricated, which realized the visible and on-site detection of Enr and Cip in the real samples of egg and milk.

In addition to highly active catalytic sites, mass transfer, especially diffusion of the reactant/product also play important roles in supported electrocatalyst systems. However, compared with the morphologies and specific surface areas, the pore structures of the catalyst supports and their influence on catalytic mass transfer have received less attention. Herein, we propose a universal in situ cavitation strategy to regulate the pore size distributions on the metal-loaded carbon through nitro modification on the molecule-based precursors, without significantly changing the electronic structures of the active metal centers. Gas sorption experiments, electrocatalytic measurements and molecular dynamic simulations certified that the increasing mesopore/macropore ratios can remarkably facilitate the diffusion coefficient, enabling improved oxygen evolution kinetics with 71 mV overpotential dropping at 10 mA.cm(-2) compared with the nitro-free counterpart. This work demonstrates that the pore size distributions of the catalyst support should be another nonnegligible parameter on boosting the overall electrocatalytic performance.

Accompanied by solid-state structural phase transitions, the switchable molecular dynamics (MD) and order-disorder transformation of (i-PrNHMe2)+ cation embedded in a deformable {[Ni(NCS)6]4−}∞ supramolecular framework are in-depth investigated by variable-temperature tests of single-crystal X-ray diffraction, dielectric measurement, and MD simulation. Interestingly, it is found that the confined swinging or flipping of the (i-PrNHMe2)+ cation as a whole is assisted by a synergistic change of its torsion angle. This research provides a helpful insight into the solid-state MD of moderate-sized quasi-spherical molecules/ions that feature a flexible inner core.

Remolding the reactivity of metal active sites is critical to facilitate renewable electricity-powered water electrolysis. Doping heteroatoms, such as Se, into a metal crystal lattice has been considered an effective approach, yet usually suffers from loss of functional heteroatoms during harsh electrocatalytic conditions, thus leading to the gradual inactivation of the catalysts. Here, we report a new heteroatom-containing molecule-enhanced strategy toward sustainable oxygen evolution improvement. An organoselenium ligand, bis(3,5-dimethyl-1H-pyrazol-4-yl)selenide containing robust C-Se-C covalent bonds equipped in the precatalyst of ultrathin metal-organic nanosheets Co-SeMON, is revealed to significantly enhance the catalytic mass activity of the cobalt site by 25 times, as well as extend the catalyst operation time in alkaline conditions by 1 or 2 orders of magnitude compared with these reported metal selenides. A combination of various in situ/ex situ spectroscopic techniques, ab initio molecular dynamics, and density functional theory calculations unveiled the organoselenium intensified mechanism, in which the nonclassical bonding of Se to O-containing intermediates endows adsorption-energy regulation beyond the conventional scaling relationship. Our results showcase the great potential of molecule-enhanced catalysts for highly efficient and economical water oxidation.

L-kynurenine (L-kyn) is a marker of prostate cancer.At present,the expensive instruments are usually applied to detect L-kyn clinically,which limits its wide application for cancer diagnosis.Herein,three lanthanide metal-organic frameworks ([Ln(CHO2)3]n,Ln Eu,Gd,and Tb) were designed and obtained,and detailly characterized by single crystal X-ray diffraction (SCXRD),powder X-ray diffraction(PXRD),Fourier transform infrared spectroscopy (FT-IR),thermogravimetric analysis (TGA),and lumi-nescence spectroscopy.Further study reveals that[Tb(CHO2)3]n is a highly selective,ultra-sensitive,of strong anti-interference,highly stable,and non-expensive sensor for prostate cancer marker L-kyn.The limit of detection (LOD) for L-kyn sensing is a highly sensitive value of 1.0 × 10-9 mol/L.Furthermore,the sensing mechanism is discussed in detail.

The level of L-kynurenine (L-kyn) can reflect the health state of human body, and the determination of L-kyn can be used for the medical diagnosis of several cancers and neurological diseases. In this work, a series of air-, water-, and thermo-stable dinuclear lanthanide nanoclusters [Ln2(2,5-DFBA)6(phen)2] (Tb 1, Eu 2, Gd 3, 2,5-DFBA = 2,5-difluorobenzoic acid, phen = 1,10-phenanthroline) are obtained by a facial method. 1 and 2 show very high luminescence quantum yields (QYs) of 71.7% and 81.8%, respectively. Interestingly, investigation reveals that 1 is a quick, highly sensitive and selective sensor for L-kyn in real samples of urine and serum. Furthermore, transmission electron microscope (TEM) results reveal that nanocluster 1 is stable in solution and can be uniform distributed on the base, suggesting it can be deposited on various supports to fabricate sensing devices. Thus, 1 is fabricated into a sensitive test paper for the eye-readable detection of L-kyn in real samples of human urine and serum. The limit of detection (LOD) as low as 0.3 μM, which is enough to rapidly determine L-kyn in human body liquor (usually 5 μM in healthy human body).

It is critical to synthesize high-efficiency electrocatalysts to boost the performance of water splitting to meet the requirements of industrial applications. Metal-organic frameworks (MOFs) can function as ideal molecular platforms for the design of highly reactive transition metal phosphides (TMPs), a kind of candidates for high-efficiently electrocatalytic water splitting. The intrinsic activity of the electrocatalysts can be greatly improved via modulating the electronic structure of the catalytic center through the MOF precursors/templates. Moreover, the carbon layer converted in-situ by the organic ligands can not only protect the TMPs from being degraded in the harsh electrochemical environments, but also avoid agglomeration of the catalysts, thereby promoting their activities and stabilities. Furthermore, heteroatom-containing ligands can incorporate N, S or P, etc. atoms into the carbon matrixes after conversion, regulating the coordination microenvironments of the active centers as well as their electronic structures. In this review, we first summarized the latest developments in MOF-derived TMPs by the unique advantages in metal, organic ligand, and morphology regulations for electrocatalytic water splitting. Secondly, we concluded the critical scientific issues currently facing for designing state-of-the-art TMP-based electrocatalysts. Finally, we presented an outlook on this research area, encompassing electrocatalyst construction, catalytic mechanism research, etc.

稀土由于具有f电子,因此稀土?有机框架发光材料具有多样结构和独特的4f电子跃迁发光性质,被广大研究者们青睐.在绿色、环保、温和的水热条件下,选用Eu3+作为中心离子,通过引入配体四氟间苯二甲酸和辅助配体1,10?菲咯啉,合成了分子式为[Eu2(TFBA)6(phen)2(H2O)2]n(1-Eu,其中TFBA为脱质子的四氟间苯二甲酸,phen为1,10?菲咯啉)的稀土?有机框架材料.同时,利用X射线粉末衍射法(PXRD)、热重分析法(TGA)、傅里叶红外光谱法(FT-IR)等测试方法对1-Eu进行了详细的表征,确定了其准确结构和稳定性能,深入分析了其激发和发射光谱、荧光衰减寿命及荧光量子产率.实验结果表明:1-Eu是一个二维结构的稀土?有机框架材料,其荧光衰减寿命为0.652 ms,具有55.28％的高荧光量子产率(QY);除此之外,1-Eu还具有良好的耐水稳定性、热稳定性及耐酸碱性质.

Tuftsin是一种对人体具有特殊生理作用的生物活性肽.该文以Tuftsin为模板分子,以丙烯酸为单体,在多孔聚偏氟乙烯基膜上制备高选择性Tuftsin-丙烯酸分子印迹复合膜(T-AA MICM),并研究其吸附分离行为.研究结果表明:分子印迹复合膜具有优良的吸附性能和特异性选择吸附性能,Tuftsin在分子印迹复合膜上的吸附过程主要是单分子吸附过程,其吸附动力学行为规律符合准2级吸附方程.

Two series of terbium complexes of Tb-2(4-BMBA)(6)(phen)(2) (Tb-Br, 4-BMBA=4-Br-3-methylbenzoic acid, phen=1,10-phenanthroline) and Tb-2(4-IMBA)(6)(phen)(2) (Tb-I, 4-IMBA=4-I-3-methylbenzoic acid) are synthesized by varying the single factor of electron-acceptor property of substituent group Br and I at para-position of 3-methylbenzoic acid. They crystalize in the same space group, ligand and metal ions are arranged in the same mode. Interestingly, the luminescence quantum yield (QY) of Tb-Br is greater than Tb-I, indicating that weaker electron-acceptor group of I at para-position of 3-methylbenzoic acid leads to lower luminescence QY than Br in terbium complex. This is the first work to control the single variable factor to study the substituent group property on the luminescence QY of lanthanide complex. Further study reveals that Tb-I is a multiplex sensor for Fe2+, Co2+, and Ni2+.

Real-time and visual monitoring of pollutants in the air is of great importance since they are usually cannot be seen, smelled, or touched. Lanthanide nano-cluster is a kind of luminescent sensor for various species. However, controlling synthesis of lanthanide nano-cluster remains experimentally challenging. In this work, four series of lanthanide-barium (Ln-Ba) nano-clusters of Dy2Ba (1), Tb2Ba2 (2), Ln4Ba3 (Ln = Tb, 3a; Eu, 3b), Tb4Ba4 (4) were assembled through precisely controlling the pH of the reactant solutions. The work features the first example that the number of cluster's nuclei changes regularly with the pH. Moreover, investigation reveals that nano-cluster 3a is a highly selective and sensitive sensor towards acetylacetone (acac) and aniline. Interestingly, easy-to-use sensing devices of test paper, agarose gel, and five kinds of film on CaCO3, polyfoam, coin, mask, and wall that based on 3a were fabricated by facile methods. The seven sensing devices showed remarkable ability to sense aniline and acac vapors with visibility to the naked eyes. This is the first work on multiple real-time and visual sensing devices based on the lanthanide nano-cluster.

Three cadmium(II) coordination polymers constructed from 5,7-disulfonate-1,4-naphthalenedicarboxylate and N-containing ligands, {[Cd-2(DSNPDC)(phen)(H2O)(4)]center dot 2.5H(2)O}(n) (1), {[Cd-2(DSNPDC)(phen)(2)(H2O)(4)]center dot 3H(2)O}(n) (2) and [Cd-2(DSNPDC)(bpy)(2)(H2O)(4)](n) (3) (H-4-DSNPDC = 5,7-disulfonate-1,4-naphthalenedicarboxylic acid, phen = 1,10-phenanthroline, and bpy = 2,2 '-bipyridine), were synthesized and characterized. Compound 1 displays a two-dimensional (2D) layered structure. In 2 and 3, the dinuclear [Cd-2(COO)(2)] units are connected by DSNPDC4- ligands to generate one-dimensional (1D) chains. Due to the presence of the terminal chelating phen/bpy ligands, all compounds show low dimensional structures. Compounds 1-3 exhibit fluorescence emissions centered at 378, 419 and 376 nm, respectively, which are assigned to ligand-centered emissions or ligand-to-metal charge transfer.

Two coordination polymers based on the mixed ligands of bipheny1-3,3'-disulfony1-4,4'-dicarboxylate (BPDSDC4-) and 2,2'-bipyridine (2,2'-bpy), {[Cd(BPDSDC)(0.5)(2,2'-bpy)(H2O)]center dot(H2O)}(n) (1) and {[Cd(BPDSDC)(0.5)(2,2'-bpy)(2)]center dot(H2O)}(n) (2) were synthesized. Both compounds crystallize in the monoclinic system, space group P2(1)/n. For 1, a = 7.5737(2), b = 17.4284(5), c = 13.5982(5) angstrom, beta = 90.788(3)degrees, V = 1794.76(10) angstrom(3) , Z = 4, C17K5N2O7 SCd, M-r = 503.77, D-c = 1.864 g/cm(3), mu = 1.378 mm(-1), F(000) = 1004, the final R = 0.0299 and wR = 0.0644 for 3137 observed reflections with I > sigma(I). For 2, a = 13.3097(2), b = 10.66240(10), c = 17.6583(3) angstrom, beta = 91.779(2)degrees, V = 2504.74(6) angstrom(3) , Z = 4, C27H21N4O6SCd, M-r = 641.94, D-c = 1.702 g/cm(3), mu = 1.008 mm(-1), F(000) = 1292, the final R = 0.0244 and wR = 0.0583 for 4594 observed reflections with I > 2 sigma(I). The Cd(II) atoms in both compounds are six-coordinated. In 1, the Cd(2,2'-bpy)(2) units are connected by BPDSDC4- ligands to generate a one-dimensional (1D) ribbon structure. The 1D ribbons are linked by the hydrogen bonds and pi center dot center dot center dot pi interactions to give a three-dimensional (3D) structure. In compound 2, the Cd(2,2'-bpy)(2) units are linked by the BPDSDC4- ligands to form a 1D chain. Compounds 1 and 2 show luminescent emissions.

以Ti2AlC为前驱体,以盐酸与氟化锂的溶液为刻蚀剂,在40℃磁力搅拌条件下,刻蚀48 h制得Ti2CTx材料.分别采用N2吸附/脱附、X-射线衍射、拉曼光谱、扫描电子显微镜、能量色散X-射线光谱仪和透射电镜等方法对试样的比表面积、孔分布、晶相结构、形貌特征等物理性质进行了表征;用循环伏安、恒流充放电和交流阻抗等电化学方法研究了Ti2CTx材料在2 mol·L-1 KOH溶液中的电化学特性.实验结果表明:Ti2CTx是2维层状材料,在电流密度为1 A·g-1时,该材料的比容量为119 F·g-1,经10000次充放电循环后,比容量保留率为98％,且保持较高的库伦效率.