Catalytic Active Sites Research Articles

CoFe phosphide conversion to heterojunction metal phosphide (CoFeP) electrocatalysts for water splitting

Many researchers have made efforts on designing and synthesizing catalytic active site as well as deciphering how exactly they catalyze the reaction to obtain electrocatalysts with superior water splitting activity. However, the development of high-performance dual-functional non-precious metal electrocatalysts for Hydrogen Evolution Reaction (HER) and Oxygen Evolution Reaction (OER) remains challenging. In this study, CoFe undergoes in a one-step phosphorylation reaction converted to Fe2P, CoP2 and Co2P, abbreviated as heterojunction metal phosphide (CoFeP). The Co/Fe ratio can be flexibly adjusted by controlling the content of Co in the synthesis process, which results in CoFeP with different morphologies. Benefiting from the porous structure and higher catalytic active sites, the Co-0.0032-FeP presents a lower overpotential of 127 mV and 266 mV for HER and OER of 10 mA cm−2 in a KOH solution, respectively. In addition, the low Tafel Slope and stable current density of Co-0.0032-FeP indicate fast kinetics and high stability in the HER.

Constructing novel Sn-Mo bimetallic sulfide heterostructures for enhanced catalytic performance towards the hydrogen evolution reaction

Understanding the design principles of efficient electrocatalysts using the structure–activity relationship is crucial for the advancement of energy-related applications, and specifically the hydrogen evolution reaction (HER). Non-precious electrocatalysts with low overpotentials are essential for driving the HER and achieving high energy efficiency. In this study, we synthesized and thoroughly investigated various heterostructures combining Mo and Sn sulfides, ranging from complete phase-separated hybrids to homogeneous mixtures: SnS@MoS2 core–shell structures, SnS/MoS2 with edge-rich Mo and (SnxMo1-x)S with uniformly distributed Sn-Mo. Our findings reveal that the SnS@MoS2 structure exhibited relatively high intrinsic activity characterized by a high electrochemical active surface area and rapid charge transfer kinetics, thereby enhancing the HER catalytic performance. The presence of fluffy MoS2 layers provided an abundance of optimized sites for HER, potentially due to strain and defects such as S vacancies, known as active catalytic sites. The optimal structure facilitated efficient charge transfer from the core to the shell, improving conductivity and catalytic activity. Our research highlights the advantages of a core–shell hybrid structure, offering guiding principles for the development of an optimal SnS@MoS2 catalyst.

Peri active site catalysis of proline isomerisation is the molecular basis of allomorphy in β-phosphoglucomutase

Metabolic regulation occurs through precise control of enzyme activity. Allomorphy is a post-translational fine control mechanism where the catalytic rate is governed by a conformational switch that shifts the enzyme population between forms with different activities. β-Phosphoglucomutase (βPGM) uses allomorphy in the catalysis of isomerisation of β-glucose 1-phosphate to glucose 6-phosphate via β-glucose 1,6-bisphosphate. Herein, we describe structural and biophysical approaches to reveal its allomorphic regulatory mechanism. Binding of the full allomorphic activator β-glucose 1,6-bisphosphate stimulates enzyme closure, progressing through NAC I and NAC III conformers. Prior to phosphoryl transfer, loops positioned on the cap and core domains are brought into close proximity, modulating the environment of a key proline residue. Hence accelerated isomerisation, likely via a twisted anti/C4-endo transition state, leads to the rapid predominance of active cis-P βPGM. In contrast, binding of the partial allomorphic activator fructose 1,6-bisphosphate arrests βPGM at a NAC I conformation and phosphoryl transfer to both cis-P βPGM and trans-P βPGM occurs slowly. Thus, allomorphy allows a rapid response to changes in food supply while not otherwise impacting substantially on levels of important metabolites.

Evolution of the Pd0/PdO phase change on Pd-MCM-41 catalyst for efficient production of furfural from the fast pyrolysis of cellulose

Furfural (C5H4O2) is a high-value platform chemical that is traditionally derived from the solvolysis of hemicellulose. However, its production from pyrolysis is far from satisfactory. In particular, the abundant cellulose within lignocellulosic biomass has yet to be successfully upgraded into furfural. Consequently, the overall yield of furfural from a lignocellulosic biomass is extremely low. Herein, we report a facile heterogeneous catalyst prepared from a simple impregnation of palladium (Pd) onto MCM-41 mesoporous silica. The catalyst demonstrated a remarkably high selectivity of ∼58.5% and yield of ∼32.5 wt% for furfural from the fast pyrolysis of wet cellulose. It was also confirmed to reach a selectivity of 65.4% and yield of 44.5 wt% for furfural from wet xylan, as well as a furfural yield of 23.9 wt% from wet sugarcane bagasse. All these values are superior to the literature reports. Through advanced characterisation including in-situ synchrotron high-temperature XRD and DRIFTS measurement, the loading of Pd in a tiny quantity of 1 mol% was confirmed to be sufficient in enhancing the surface hydrophilicity of the MCM-41 support, promoting the adsorption of reactants especially the formaldehyde group (HCHO), as well as the desorption of the target product furfural. In addition, Pd oxide (i.e., Pd2+O) was confirmed to be the catalytic active site. However, it was partly reduced into metallic Pd0 during the cellulose pyrolysis, due to the preferred reduction by adsorbed formaldehyde group and other reductants including H2 and CO in the vicinity of the PdO sites on the Pd-O-Si interface. Nevertheless, the catalyst was proven to retain the memory of its initial state after combustive regeneration in air, having oxidation state of Pd, particle size, and dispersion degree being reversed to its original construction. Accordingly, its activity remained stable upon cyclic testing. All these results demonstrate a high practical viability of this heterogenous catalyst for the valorisation of cellulose-rich biomass, an otherwise abundant crop waste across the world.

Fabrication of magnetic carbohydrate-modified iron oxide nanoparticles (Fe3O4/pectin) decorated with bimetallic Co/Cu-MOF as an effective and recoverable catalyst for the Biginelli reaction.

Due to their biocompatibility, facile recoverability, mechanical and thermal stability, high surface area, and active catalytic sites, magnetic nanocomposites, containing natural polymers and magnetic nanoparticles, have been used to produce supports for catalysts or biocatalysts. Pectin, an important polycarbohydrate, has abundant functional groups with excellent ability to coat the surface of the nanoparticles to fabricate composite and hybrid materials. A novel bimetallic cobalt(ii) and copper(ii)-based metal-organic framework (Co/Cu-MOF) immobilized pectin-modified Fe3O4 magnetic nanocomposite was designed and fabricated. Fe3O4 nanoparticles were modified in situ by pectin and, subsequently, used as a support for growing Co/Cu-MOF [Fe3O4/pectin/(Co/Cu)MOF]. The properties of the nanocomposite were investigated by FT-IR, XRD, SEM, EDS, VSM, STA, and BET. The nanocomposite exhibited both magnetic characteristics and a high surface area, making it a suitable candidate for catalytic applications. Then, the Fe3O4/pectin/(Co/Cu)MOF nanocomposite was utilized in the Biginelli reaction for the production of biologically active dihydropyrimidinones. Due to paramagnetism, Fe3O4/pectin/(Co/Cu)MOF was easily recovered and reused in six cycles without significant loss in reactivity. This green method comprises several benefits, such as mild reaction conditions, free-solvent media, high yields, easy workup, short reaction times and reusability of the prepared catalyst.

0D/2D Schottky heterojunction of CsPbBr3 nanocrystals on MoN nanosheets for enhancing charge transfer and CO2 photoreduction

Solar-driven conversion of CO2 to value-added chemical fuels has been regarded as a promising strategy for solving the climate problem and energy crisis. To realize this goal, it is vital to design photocatalysts with abundant catalytic active sites and excellent charge separation efficiency. Here, perovskite nanocrystals (CsPbBr3) were anchored on two-dimensional molybdenum nitride (MoN) using an in-situ growth method, forming a new and effective 0D/2D CsPbBr3@MoN (CPB@MoN) nanoheterosturcture with close contact interface for CO2 photoreduction. The introduction of MoN, acting as a charge transfer channel, could quickly trap the photoinduced charge from CsPbBr3 and provide abundant catalytic sites for CO2 photocatalytic reactions. For optimized CsPbBr3@MoN composites, the CO yield was 13.86μmol/gh−1 without any sacrificial reagent, which was a 4.5-fold enhancement of the pure CsPbBr3. Further, in-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) revealed the catalytic mechanism for the CO2 photoreduction process. This work provides a new platform for constructing superior perovskite/MoN-based photocatalysts for photocatalytic CO2 reduction.

Single active Au1O5 clusters for metabolism-inspired sepsis management through immune regulation

Artificial enzymes with reprogrammed and augmented catalytic activities hold significant potential in biomedicine. However, common issues with biocatalysts are the presence of numerous inactive site atoms, leading to inefficiencies in their catalytic processes. To leverage the full potential of active catalytic sites, we aim to minimize the biocatalyst structure, transitioning from nanoparticles or polymetallic atomic clusters down to singular-active-unit molecules. In this context, we have developed a unique single active-site cluster molecule, Au1-O5-Na9-(OH)4 (AuO) clusters, comprising a single gold atom, five oxygen atoms, and a protective layer, where Au-O acts as a singular-active site displaying elevated catalytic activities without inefficiencies associated with biocatalytic reactions. AuO clusters demonstrate activities reminiscent of nicotinamide adenine dinucleotide oxidase (NOX), glutathione peroxidase (GPx), and urease, among other oxidoreductase functions, through optimal utilization of atoms. Clusters are instrumental in enhancing the redox balance, mitigating inflammation, and averting inflammation-induced cellular apoptosis, thereby preserving immune balance in sepsis. These mechanisms are crucial in sepsis pathogenesis. Demonstrating GPx-like and NOX-like capabilities, the AuO clusters have shown remarkable effectiveness against lipopolysaccharide-induced and cecum ligation puncture-induced multiorgan damage, underscoring their substantial promise for sepsis management.

Exploring PtAg onto silanized biogenic silica as an electrocatalyst for H2 evolution: A combined experimental and theoretical investigation

The task of creating a remarkably stable and effective electrochemical catalyst for efficient hydrogen evolution is arduous, primarily due to the multitude of factors that need to be taken into account for the industrial utilization of Pt. In this work, hybrid formation through in-situ reduction of Pt onto biogenic porous silica (Pt-SiO2) is tested for its use as an efficient catalyst for hydrogen production. Exceptionally high electrocatalytic activity and excellent reusability of catalysts up to 200 cycles have been demonstrated. Pt-SiO2 with low Pt content of 0.48 to 0.82 at% with active catalytic sites exhibit superior catalytic activity with a Tafel slope of 22 mV dec−1 and an overpotential of 28 mV (vs. RHE at 10 mA cm−2) as compared to the Pt wire and previously reported bare Pt-SiO2 (0.65 at% and 0.48 at% of Pt), and hybrid (Pt/Ag) structures formed onto two different biogenic porous SiO2 substrates. The best catalytic performance of the Pt1Ag3 cluster, representing a low Pt concentration, has been validated by Density Functional Theory (DFT) calculations. Here, the high production from the Pt1Ag3 cluster is assigned to the mutual synergistic effect between Pt/Ag atoms. The Pt atoms transfer the excess charge to the nearest Ag neighbors inside the cluster, facilitating hydrogen diffusion on the activated sites. These important findings authenticate the superior hydrogen production at reduced Pt concentration on amine-functionalized biogenic porous silica.

Bifunctional silver-metal organic gels with catalytic and electrochemiluminescence properties applied for ratio detection of I27L gene

The rate of maturity-onset diabetes of the young (MODY) is significantly increased by the common I27L gene variant of the hepatocyte nuclear factor-1α (HNF1A), hence achieving sensitive and precise I27L gene detection is the focus of early monitoring and diagnosis of HNF1A-MODY. In this study, we developed a silver-metal organic gels (Ag MOGs)/ K2S2O8-O2 system-based electrochemiluminescence resonance energy transfer (ECL-RET) ratio biosensor for detecting the I27L gene. The novel Ag MOGs were synthesized by simply mixing Ag+ and Luminol at ambient temperature. On the one hand, Ag MOGs could generate excellent anodic ECL signals in phosphate buffer without requiring exogenous co-reactants, which were derived from the Luminol ligand. On the other hand, Ag MOGs facilitated the electrocatalytic reduction of K2S2O8 by providing stable catalytic active sites and enhancing electron transfer rates, thereby leading to enhanced cathodic ECL emission from K2S2O8-O2. We constructed an ECL-RET ratio biosensor utilizing a DNA walker cycle amplification strategy. The biosensor leveraged the anodic ECL emission from the Ag MOGs/K2S2O8-O2 system as a donor and Atto 425 as a receptor, achieving ultra-sensitive detection of the I27L gene within a linear range of 100 amol/L to 100 pmol/L, and featuring a detection limit of 72 amol/L. Therefore, a direct synthesis technique of bifunctional materials with catalysis and electrochemiluminescence has been developed. Additionally, the ECL-RET ratio biosensor provided a universal platform for the detection of diabetes subtypes.

Phosphorus and nitrogen co-doped-graphene: Stability and catalytic activity in oxygen reduction reaction

This study systematically investigated the stable configurations and oxygen reduction reaction (ORR) catalytic activity of PN co-doped graphene using first-principles methods. We found that PN co-doped graphene substrates are generally highly stable. The adsorption energy of adsorbates is linearly positively correlated with the number of electrons obtained from the substrate. The P atoms serve as catalytic activity sites, the co-doping of N significantly enhances the adsorption energies of intermediate species in the ORR process, facilitating the direct dissociation of O2 and O2H. The solvation effect has a non-negligible impact on the adsorption energy of adsorbates, especially for O2. Due to the excessive adsorption of O, it poisons and inhibits the catalytic activity of P active sites for ORR. However, after O adsorption, the C atoms neighboring the PN impurity atoms in the P-Nn-Gra (n=2,3) substrates exhibit better catalytic activity than that of graphene doped with P/N alone. The P-Nn-defect-Gra (n=2,3,4) substrates are potential catalysts with good HER catalytic activity.

Generating highly active oxide-phosphide heterostructure through interfacial engineering to break the energy scaling relation toward urea-assisted natural seawater electrolysis

Urea-assisted natural seawater electrolysis is an emerging technology that is effective for grid-scale carbon–neutral hydrogen mass production yet challenging. Circumventing scaling relations is an effective strategy to break through the bottleneck of natural seawater splitting. Herein, by DFT calculation, we demonstrated that the interface boundaries between Ni2P and MoO2 play an essential role in the self-relaxation of the Ni–O interfacial bond, effectively modulating a coordination number of intermediates to control independently their adsorption-free energy, thus circumventing the adsorption-energy scaling relation. Following this conceptual model, a well-defined 3D F-doped Ni2P-MoO2 heterostructure microrod array was rationally designed via an interfacial engineering strategy toward urea-assisted natural seawater electrolysis. As a result, the F-Ni2P-MoO2 exhibits eminently active and durable bifunctional catalysts for both HER and OER in acid, alkaline, and alkaline seawater-based electrolytes. By in-situ analysis, we found that a thin amorphous layer of NiOOH, which is evolved from the Ni2P during anodic reaction, is real catalytic active sites for the OER and UOR processes. Remarkable, such electrode-assembled urea-assisted natural seawater electrolyzer requires low voltages of 1.29 and 1.75 V to drive 10 and 600 mA cm−2 and demonstrates superior durability by operating continuously for 100 h at 100 mA cm−2, beyond commercial Pt/C ‖ RuO2 and most previous reports.

Low-temperature subcritical water dechlorination composites of waste PVC/coal fly ash with powerful sensing activity for chemiluminescent detection of acetamiprid and imidacloprid

Pesticide residues in agricultural products are serious threat to people's health. Real-time monitoring of pesticides residues in the environment and agricultural products posed challenges to sustainable methods with high analytical performance for pesticide detection. Herein, waste PVC/coal fly ash (the mass ratio of PVC and coal fly ash was 4:1) was dechlorinated in subcritical water at low temperature to achieve nearly 100 % dechlorination of PVC and obtain carbon-based composite materials (CM-Fe/Al/Si-dPVC) with strong sening activity. For CM-Fe/Al/Si-dPVC, CFe bonding resulted in strong electron migration, and nano/μm SiO2 and Al2O3 doping in the layered polyene C matrix provided large specific surface area, and silicon hydroxyl created good heterogeneous catalytic interfaces. CM-Fe/Al/Si-dPVC could strongly trigger luminol chemiluminescence (CL) reaction and produce intense CL signals. Neonicotinoid pesticides (acetamiprid and imidacloprid) bonded with CM-Fe/Al/Si-dPVC through coordination chelation and hydrogen bonding, which shielded the catalytic active site and increased the Fermi level of system, thus quenching CL reaction. Inspired by these, a cheap CL assay was constructed for detecting neonicotinoids combinations of acetamiprid and imidacloprid (NICs). The detection limits of NICs were 0.7 ng/L. Satisfactory recoveries were obtained for real agricultural products and environmental samples. The results of life cycle evaluation (LCA) revealed that the strategy had significantly small global warming potential (GWP). This work presented a sustainable method with environmental benefits for the detection of neonicotinoids, and also opened up new way for the recycling of organic solid wastes.

Ultrasmall Pd nanoparticles supported on a metal–organic framework DUT-67-PZDC for enhanced formic acid dehydrogenation

The highly dispersed ultrasmall palladium nanoparticles (Pd NPs) (1.7 nm) were successfully immobilized on a N-containing metal–organic framework (MOF, DUT-67-PZDC) using a co-reduction method, and it is used as an excellent catalyst for formic acid dehydrogenation (FAD). The optimized catalyst Pd/DUT-67-PZDC(10, 10 wt% Pd loading) shows 100% hydrogen (H2) selectivity and formic acid (FA) conversion at 60 °C, and the commendable initial turnover frequency (TOF) values of 2572 h−1 with the sodium formate (SF) as an additive and 1059 h−1 even without SF, which is better than most reported MOF supported Pd monometallic heterogeneous catalysts. The activation energy (Ea) of FAD is 43.2 KJ/mol, which is lower than most heterogeneous catalysts. In addition, the optimized catalyst Pd/DUT-67-PZDC(10) maintained good stability over five consecutive runs, demonstrating only minimal decline in catalytic activity. The outstanding catalytic performance could be ascribed to the synergistic corporations of the unique structure of DUT-67-PZDC carrier with hierarchical pore characteristic, the metal-support interaction (MSI) between the active Pd NPs and DUT-67-PZDC, the highly dispersed Pd NPs with ultrafine size serve as the catalytic active site, as well as the N sites on the support could act as the proton buffers. This work provides a new paradigm for the efficient H2 production of FAD by constructing highly active heterogeneous Pd-based catalysts using MOF supports.

Synthesis, biological evaluation, molecular docking, and MD simulation of novel 2,4-disubstituted quinazoline derivatives as selective butyrylcholinesterase inhibitors and antioxidant agents

Alzheimer’s disease is the most prevalent neurodegenerative disorder characterized by significant memory loss and cognitive impairments. Studies have shown that the expression level and activity of the butyrylcholinesterase enzyme increases significantly in the late stages of Alzheimer’s disease, so butyrylcholinesterase can be considered as a promising therapeutic target for potential Alzheimer’s treatments. In the present study, a novel series of 2,4-disubstituted quinazoline derivatives (6a–j) were synthesized and evaluated for their inhibitory activities against acetylcholinesterase (AChE) and butyrylcholinestrase (BuChE) enzymes, as well as for their antioxidant activities. The biological evaluation revealed that compounds 6f, 6h, and 6j showed potent inhibitory activities against eqBuChE, with IC50 values of 0.52, 6.74, and 3.65 µM, respectively. These potent compounds showed high selectivity for eqBuChE over eelAChE. The kinetic study demonstrated a mixed-type inhibition pattern for both enzymes, which revealed that the potent compounds might be able to bind to both the catalytic active site and peripheral anionic site of eelAChE and eqBuChE. In addition, molecular docking studies and molecular dynamic simulations indicated that potent compounds have favorable interactions with the active sites of BuChE. The antioxidant screening showed that compounds 6b, 6c, and 6j displayed superior scavenging capabilities compared to the other compounds. The obtained results suggest that compounds 6f, 6h, and 6j are promising lead compounds for the further development of new potent and selective BuChE inhibitors.

A confined catalysis strategy: Lewis acid-base (B/Br) and hydrogen bond donor (-OH) multi-functionalized core-shell catalyst for CO2 cycloaddition

In recent years, a significant number of metal-based catalysts were synthesized for the CO2 cycloaddition reaction. However, the leaking of active metal elements resulted in various environmental issues. To prevent the loss of active components and enhance the catalyst lifespan, a confined catalysis strategy involving a multi-functionalized core-shell catalyst with Lewis acid-base (B/Br) and hydrogen bond donor (-OH) was designed. It was noteworthy that B-mSiO2@MCM-IMOH featured multifunctional catalytic active sites, including Lewis acid-base (B/Br) and hydrogen bond donor (-OH), and the cooperative effect of B, Br and -OH significantly improved the catalytic activity. Therefore, B-mSiO2@MCM-IMOH demonstrated outstanding catalytic performance for the CO2 cycloaddition reaction. In addition, the core-shell molecular sieve, serving as a confined catalytic carrier, effectively enhanced the stability and recyclability of the catalyst. Utilizing DFT calculations, a cooperative catalytic mechanism was proposed involving Lewis acid-base (B/Br) and hydrogen bond donor (-OH). The synergistic interaction between B/Br and -OH markedly reduced the energy barrier for the ring-opening of propylene oxide from 58.6 kcal·mol−1 to 21.5 kcal·mol−1, thus facilitating the PO-CO2 cycloaddition reaction.

Revealing the Electrocatalytic Reaction Mechanism of Water Splitting by In Situ Raman Technique

AbstractUsing renewable energy for water splitting to produce hydrogen is a crucial step toward achieving the dual carbon goals. However, due to the lack of a clear understanding of the precise localization of catalytic active sites and the complex structural evolution of catalysts during actual reaction conditions, there is still a challenge to reveal the electrocatalytic reaction mechanism of water splitting. In situ electrochemical Raman characterization technique can dynamically monitor the structural evolution of catalysts in real time, reveal the dynamic structure‐performance relationship of catalysts during the reaction process, and explore the catalytic reaction mechanism. This paper focuses on reviewing the latest developments in in situ electrochemical Raman characterization technology in terms of active sites on catalyst surfaces, the behavior of interfacial water molecules, and the structure evolution of electrocatalysts. The future development prospect of advanced in situ electrochemical Raman technology is also prospected.

The evaluation and mechanism study of zerovalent iron (Fe0) catalysts supported on coke for NO reduction by H2

Coke supported highly dispersed zerovalent iron Fe0 catalysts were synthesized and their catalytic activity in the reduction of NO by H2 was investigated using a fixed-bed reactor. The effect of H2 concentration on dispersion of active component Fe0 and activity of catalyst during preparation was investigated and density functional theory (DFT) simulation was used to study the reaction mechanism and the reason for catalyst deactivation. The Fe0 catalyst has a strong catalytic ability to reduce NO with H2. The activity of catalyst initially increased and then decreased in the increase of hydrogen concentration during the preparation. The carrier coke is not consumed in the reaction, which improves the dispersion of the active component Fe0. However, Fe0 catalyst is oxidized in the NO reduction, resulting in a decrease in the catalyst activity. The DFT calculations results suggest that the NO reduction follows the E-R mechanism, and the presence of Fe0 makes the N-O bond easily break to form N2. H2 has the capability to reduce oxidized Fe0 and release the catalytic active site, but the energy barrier that needs to be overcome is greater than that of oxidation of Fe0, which eventually leads to catalyst deactivation.

Ceanothanes Derivatives as Peripheric Anionic Site and Catalytic Active Site Inhibitors of Acetylcholinesterase: Insights for Future Drug Design.

Alzheimer's disease (AD) is a multifactorial and fatal neurodegenerative disorder. Acetylcholinesterase (AChE) plays a key role in the regulation of the cholinergic system and particularly in the formation of amyloid plaques; therefore, the inhibition of AChE has become one of the most promising strategies for the treatment of AD, particularly concerning AChE inhibitors that interact with the peripheral anionic site (PAS). Ceanothic acid isolated from the Chilean Rhamnaceae plants is an inhibitor of AChE through its interaction with PAS. In this study, six ceanothic acid derivatives were prepared, and all showed inhibitory activity against AChE. The structural modifications were performed starting from ceanothic acid by application of simple synthetic routes: esterification, reduction, and oxidation. AChE activity was determined by the Ellmann method for all compounds. Kinetic studies indicated that its inhibition was competitive and reversible. According to the molecular coupling and displacement studies of the propidium iodide test, the inhibitory effect of compounds would be produced by interaction with the PAS of AChE. In silico predictions of physicochemical properties, pharmacokinetics, drug-likeness, and medicinal chemistry friendliness of the ceanothane derivatives were performed using the Swiss ADME tool.

Boosting Interfacial Electron Transfer and CO2 Enrichment on ZIF-8/ZnTe for Selective Photoelectrochemical Reduction of CO2 to CO.

Artificial photosynthesis is an effective way of converting CO2 into fuel and high value-added chemicals. However, the sluggish interfacial electron transfer and adsorption of CO2 at the catalyst surface strongly hamper the activity and selectivity of CO2 reduction. Here, we report a photocathode attaching zeolitic imidazolate framework-8 (ZIF-8) onto a ZnTe surface to mimic an aquatic leaf featuring stoma and chlorophyll for efficient photoelectrochemical conversion of CO2 into CO. ZIF-8 possessing high CO2 adsorption capacity and diffusivity has been selected to enrich CO2 into nanocages and provide a large number of catalytic active sites. ZnTe with high light-absorption capacity serves as a light-absorbing layer. CO2 molecules are collected in large nanocages of ZIF-8 and delivered to the ZnTe surface. As evidenced by scanning electrochemical microscopy, the interface can effectively boost interfacial electron transfer kinetics. The ZIF-8/ZnTe photocathode with unsaturated Zn-Nx sites exhibits a high Faradaic efficiency for CO production of 92.9% and a large photocurrent of 6.67 mA·cm-2 at -2.48 V (vs Fc/Fc+) in a nonaqueous electrolyte at AM 1.5G solar irradiation (100 mW·cm-2).

Nano FeNi-OH/Co(OH)2/NF p-n heterojunction for efficient oxygen evolution reaction and electrocatalytic urea oxidation: Built-In electric field regulated charge distribution and mechanism exploration

Constructing electronic structures with abundant surface/interface structures and effective regulation of catalytic active centers is an effective strategy to improve electrocatalytic performance, but designing efficient bifunctional non-noble metal oxygen evolution reaction (OER) and urea oxidation reaction (UOR) electrocatalysts remains challenging. Studies have shown that p-n heterojunctions can effectively regulate the electronic structure of catalytic active sites while having abundant surface/interface structure, which plays an important role in improving the native catalytic activity. Herein, FeNi-OH/Co(OH)2/NF p-n heterojunction structure was constructed by a simple electrochemical deposition method, and the effects of content, deposition time, and number of cycles on catalytic performance were investigated. The results show that Fe(0.02 M)Ni(0.07 M)–OH(100 s)/Co(OH)2(5)/NF composite material has the best OER and UOR catalytic performance. For OER, the electrocatalyst only requires an overpotential of 271 mV to obtain a current density of 50 mA cm−2, and an applied voltage of 1.56 V to obtain a total water decomposition of 10 mA cm−2 (FeNi-OH/Co(OH)2/NF||Pt). For UOR, a voltage of only 1.314 V (vs. RHE) is required to achieve a current density of 10 mA cm−2, and an applied voltage of 1.44 V can achieve a current density of 10 mA cm−2. Experimental, in situ measurements and theoretical results indicate that the improvement in catalytic activity is mainly due to the potential difference between FeNi-OH and Co(OH)2, which induces self-driven charge transfer at the interface, promoting the adsorption of reactant molecules, optimizing reaction barriers, accelerating chemical bond cleavage, and thus promoting catalytic reactions.