Excitonic effects caused by Coulomb interactions between electrons and holes play subtle significant roles on photocatalysis, yet have been long ignored. Herein, porphyrinic covalent organic frameworks (COFs, specifically DhaTph-M), in the absence or presence of different metals porphyrin centers, shown as ideal models to regulate excitonic effects. Remarkably, incorporation Zn2+ COF facilitates conversion singlet triplet excitons, whereas Ni2+ introduction promotes dissociation excitons hot...

The strong excitonic effects widely exist in polymer-semiconductors and the large exciton binding energy (Eb) seriously limits their photocatalysis. Herein, density functional theory (DFT) calculations are conducted to assess band alignment charge transfer feature of potential donor-acceptor (D-A) covalent organic frameworks (COFs), using 1,3,5-tris(4-aminophenyl)triazine (TAPT) or 1,3,5-tris(4-aminophenyl)benzene (TAPB) as acceptors tereph-thaldehydes functionalized diverse groups donors....

Exploring the impact of active site density on catalytic reactions is crucial for reaching a more comprehensive understanding how single-atom catalysts work. Utilizing functional theory calculations, we have systematically investigated neighboring effects between two adjacent Fe-N-C sites monodispersed oxygen reduction reaction (ORR). While thermodynamic limiting potential (UL) strongly dependent intersite distance and nature in FeN3, it almost invariable FeN4 until are ∼4 Å apart. Further,...

Cobalt–salen-based porous ionic polymers, which are composed of cobalt and halogen anions decorated on the framework, effectively catalyze CO2 cycloaddition reaction epoxides to cyclic carbonates under ambient conditions. The cooperative effect bifunctional active sites as Lewis acidic site anion nucleophile responds high catalytic performance. Moreover, density functional theory results indicate that valence state corresponding coordination group influence rate-determining step...

Oxygen vacancies (OVs) play important roles on any oxide catalysts. In this work, using an investigation of the OV effects ZnO(101̅0) for CO and H2 activation as example, we demonstrate, via machine learning potentials (MLPs), genetic algorithm (GA)-based global optimization, density functional theory (DFT) validations, that surface with 0.33 ML OVs is most likely configuration under experimental conditions (673 K 2.5 MPa syngas (H2:CO = 1.5)). It found a reconstruction from wurtzite...

To evaluate the heavy metal contamination of soil and plants in Dunhua sewage irrigation area (DIA), used wastewater for at least 20 years. 270 samples different depth (0-120 cm) 23 plant were collected five sites. Physical chemical properties long-term analyzed, including texture, bulk density, pH, cation exchange capacity (CEC), organic matter; total concentrations measured using AAS AES. The average value pH was 8.01, alkaline; CEC changes from 59.35 mmol to 118.95 mmol, 80.96 mmol;...

Heterogenous single-atom catalysts (SACs) are reminescent of homogenous because similarity structural motif active sites, showing the potential using advantage to tackle challenges in hetereogenous catalysis. In heterogeneous oxygen electrocatalysis, homogeneity adsorption patterns reaction intermediates leads scaling relationships that limit their activities. contrast, homogeneous can circumvent such limits by selectively altering through secondary coordination effects (SCE). This inspired...

Heterogenous single-atom catalysts (SACs) are reminiscent of homogeneous because the similarity structural motif active sites, showing potential using advantage to tackle challenges in hetereogenous catalysis. In heterogeneous oxygen electrocatalysis, homogeneity adsorption patterns reaction intermediates leads scaling relationships that limit their activities. contrast, can circumvent such limits by selectively altering through secondary coordination effects (SCEs). This inspired us explore...

Metallosalen-based porous ionic polymers have the potential to combine merits of homogeneous organometallics and heterogeneous catalysts in carbon dioxide (CO2) cycloaddition conversion. Herein, a series metallosalen hypercrosslinked (M-HIPs) were synthesized through simple method. The M-HIPs with high metal Br anion concentrations evaluated by catalyzing CO2 epoxides. Because cooperative effect between anions active species channel, exhibited catalytic performance even under ambient...

Understanding catalyst surface structure changes under reactive conditions has become an important topic with the increasing interest in operando measurement and modeling. In this work, we develop a workflow to build machine learning potentials (MLPs) for simulating complicated chemical systems large spatial time scales, which committee model strategy equips MLP uncertainty estimation, enabling active protocol. The methods are applied constructing PtOx based on explored configurations from...

The production of ammonia from nitrogen reduction reaction (NRR) under mild conditions is one the most challenging issues in modern chemistry. linear scaling relationship between adsorption energies -N2H and -NH2 on a single active site well-established bottleneck. By investigating series densely monodispersed Mo-N-C sites embedded graphene using first-principles calculations, we found that previously underappreciated neighboring effects adjacent may help break limit: they not only improve...

Intermetal distance plays a prominent role in determining the electrochemistry-induced surface coverage of dual-atom catalysts (DACs).

As a critical component of the OX-ZEO composite catalysts toward syngas conversion, Cr-doped ZnO ternary system can be considered as model for understanding oxide catalysts. However, due to complexity its structures, traditional approaches, both experimental and theoretical, encounter significant challenges. Herein, we employ machine learning-accelerated methods, including grand canonical Monte Carlo genetic algorithm, explore ZnO(1010) surface with various Cr oxygen vacancy (OV)...

Fluorescent anti-counterfeiting technology has been widely reported for its advantages, such as easy identification and multiple functions. Most of the current fluorescent materials focus on innovation mode. However, stability is a prerequisite applying determining whether material can be used. Inspired by water stains, we report nanoparticles that are easily prepared inkjet printable have functions high stability. They applied successfully to anti-counterfeiting. 3D printed microreactors...

Direct methanol fuel cells have warranted much attention as the ideal energy-converting devices owing to their superior properties. Maximizing performance of Pt-based electrocatalysts for oxidation reaction (MOR) while minimizing adsorption toxic CO molecules during catalytic process still remains a great challenge. Herein, multi-dimensional ternary composite 3D Pt/2D-NiMOF/reduced graphene oxide (rGO) are prepared with subsized Pt nanoparticles (2.1 nm) distributed on 2D-NiMOF nanosheets...

The excellent performance of ZnxCryOz catalysts, used in the process converting CO/H2 to methanol and light olefins, is highly attractive, but microstructure structure under syngas conversion conditions remains elusive experimentally theoretically because limitation detecting facilities/methods. By using genetic-algorithm-based global structural search accelerated by machine learning combination with a local cluster sampling strategy active scheme, we reveal structure/composition evolution...

Atomically dispersed metal-nitrogen-carbon (M-N-C) materials are deemed promising catalysts for the oxygen reduction reaction (ORR) in fuel cells. Yet multilayer nature of M-N-C has been largely neglected computational analysis. To bridge gap, we conducted a first-principles investigation using bilayer models (TMNx/G-TMNy/G, TM = Mn, Fe, Co, Ni, Cu, G graphene, x, y 3 or 4), where TMs on top serves as active center. While in-plane TMN4 at bottom minimal impact ORR, out-of-plane TMN3...

Heterogenous single-atom catalysts (SACs) are reminescent of homogenous because similarity structural motif active sites, opening a window for applying merits to address issues in hetereogenous catalysis. In heterogeneous oxygen electrocatalysis, the homogeneity adsorption patterns reaction intermediates leads scaling relationships that limit their activities. contrast, homogeneous can circumvent such limits by selectively altering through secondary coordination effects (SCE). This inspired...