Regulation of the CO2 hy-drogenation process to ob-tain highly selective target products is a challenging and important research topic.In this study,we re-port the key role of PO43-anions modified on the Ru/TiO2 catalyst surface in regulating the CO2 hy-drogenation process.Ion chromatography,X-ray diffraction,X-ray photoelectron spec-troscopy,and transmission electron microscopy confirmed the successful preparation of the Ru/TiO2 catalyst modified by PO43-anions.The original Ru/TiO2 catalyst showed poor catalytic activity in CO2 hydrogenation,and the main hydrogenation product was CO.With the PO43-anion-modified Ru/TiO2 catalysts,the conversion of CO2 was clearly im-proved,and the hydrogenation product changed from CO to CH4.XPS characterization and DFT theoretical calculations confirmed that the modified PO43-anions interacted mainly with the Ru metal site on the Ru/TiO2 catalyst surface,effectively regulating the surface electronic properties of the Ru metal,which affected the conversion efficiency of CO2.In addition,CO temperature-programmed desorption and diffuse reflectance infrared Fourier transform spectroscopy characterization revealed that the adsorption of CO inter-mediates improved after the Ru metal surface was modified with PO43-anions,which was beneficial for further CO hydrogenation and the formation of CH4 products.Our work ex-pands the research strategies of anion-modified metal-based catalysts that regulate the hy-drogenation performance of CO2 and provides a new direction for further understanding the influence mechanism of the catalyst surface structure on hydrogenation performance.
Based on the transforma-tion between different phase structures,lead halide perovskite materi-als can achieve interest-ing fluorescence response to water,heat,and pres-sure.Here,we achieve a novel fluorescence response to solvents on a three-dimensional perovskite(3D,CsPbBr3)that is transformed from zero-dimensional perovskite(0D,Cs4PbBr6).The phase transfor-mation process is realized by extracting excess CsBr from Cs4PbBr6 by tungstosilicic acid(TSA).The phase transformation product(U-CsPbBr3)with more surface defects shows weak photoluminescence(PL)emission,but shows bright green PL emission immediately when it is wetted with some solvents such as methyl acetate,acetone,tetrahydrofuran,and acetonitrile.Repeatable and time-controlled fluorescence response can be achieved by ad-justing solvents with different volatility.This unique property can be possibly used in anti-counterfeiting or electrowetting display,etc.
The photodissociation of H2 near its second dissociation threshold yields two competing channels:H(1s)+H(2s)and H(1s)+H(2p).While cosine oscillations in the branching ratio,signatures of quantum interference between the two pathways,were previous-ly observed in HD and D2,they remained undetected in H2 due to the rotational state distribution of conventional molecular beams.Here,we isolate the ground rotational state(J"=0)of para-H2 and combine delay-time-curve measurements with velocity map imaging to directly resolve the branching ratios,confirming universal quantum interference across all isotopologues.The oscillations are quantitatively described by a p-wave scattering model with effective spherical potentials,where fitted parameters for H2 agree with those derived from HD,D2,and ab initio calculations.The interference arises from a phase difference between two dissociation channels,which is determined by the product of the fragment wavevector and the width difference between the two effective potentials.These results establish quantum interference as a fundamental driver of molecu-lar dissociation and provide benchmark data for refining theoretical models of multichan-nel dynamics.
Traditional receptor-ligand theo-ry prioritizes equilibrium affinity,but kinetic factors—especially the energy barriers for association and dissociation—are often important.Here,we hypothesize that protein-ligand dissociation pro-ceeds via a well-defined activation barrier that can be quantified through physically realistic simula-tions.We employ a temperature-coupled molecular dynamics(TCMD)protocol that selec-tively heats the ligand while maintaining the protein near physiological temperature,there-by promoting unbiased dissociation events without sacrificing structural integrity.The re-sulting temperature-dependent off-rate follows a theoretically consistent trend,allowing ro-bust extraction of activation energies.Applied to streptavidin-biotin benchmarks,TCMD reproduces experimental dissociation activation barriers with a mean absolute error of 1.2 kcal/mol.Beyond numerical agreement,TCMD provides high-resolution mechanistic in-sight by showing how interaction-energy fluctuations,hydrogen-bond reordering,and dis-crete conformational changes shape the exit pathway,thereby linking the estimated barrier to its structural origins.These results establish,with near-experimental fidelity,the activa-tion barrier governing dissociation,encouraging a move beyond affinity-only perspectives.Furthermore,the unbiased trajectories provide a detailed,time-resolved view of contact re-organization during dissociation,offering a realistic framework for studying binding kinet-ics at atomic resolution.
We have successfully utilized noncollinear four-wave mixing in argon to generate～160 nm fem-tosecond laser pulses,which can serve as the vacuum ultraviolet pump laser for time-resolved measurements.By performing a femtosecond time-resolved pho-toelectron imaging experiment,the ultrafast decay dynamics of pyrrole following single-photon excitation at～160 nm is investigated.Two time constants of 50+17-12 and 250±50 fs are derived based on the analysis of the time-resolved photoelec-tron spectroscopy spectra and assigned to the excited-state lifetimes of high-lying valence and Rydberg states.In particular,the analysis of the photoelectron angular distributions clearly indicates that the initially prepared valence ππ* state(s)should be of mixed valence/Rydberg character.
