The development of effective and stable photocatalysts for reducing hexavalent chromium (Cr(VI)) holds immense significance for environmental remediation, as Cr(VI) is a highly hazardous and contaminant commonly detected in industrial wastewater. In the present study, a novel Sb2S3/Co9S8 Type-II heterojunction photocatalyst was successfully synthesized using a simple solvothermal technique. The optimized SC(0.2) composite, with 0.2 g of Sb2S3, demonstrated remarkable photocatalytic Cr(VI) reduction efficiency (99.3% within 40 min) under visible light. This performance far suppress that of pristine Sb2S3 (12.2%) and Co9S8 (27.1%). The significant enhancement in performance is primarily due to the establishment of the Type-II heterojunction between Sb2S3 and Co9S8, which enhances the separation and transfer of photoexcited charge carriers, combined with a higher density of active sites for the surface redox reaction. Systematic investigations of the influencing factors affecting the reaction, such as initial Cr(VI) concentration, catalyst amount, pH level, and ionic environment, were conducted to optimize the reaction conditions. Experiments involving radical trapping indicated that electrons (e−) and superoxide radicals (•O2−) are the key reactive agents responsible for Cr(VI) reduction. Moreover, the SC(0.2) heterostructure showed remarkable stability and reusability, retaining more than 90% of its initial activity after five successive cycles. This work provides a promising approach for rational design of high-performance Sb2S3-based heterojunction photocatalysts aimed at efficient Cr(VI) reduction and wastewater purification.

ZSM-5 zeolite is widely utilized in catalytic cracking reactions for high-efficiency propylene synthesis, whereas severe carbon deposition inevitably leads to rapid catalyst deactivation, greatly limiting its long-term industrial application. Currently, the intrinsic correlation between the Si/Al ratio of ZSM-5, coke evolution pathway, and the deactivation as well as regeneration mechanism still lacks systematic and in-depth clarification. Herein, multiple characterization techniques were combined to comprehensively reveal the coke formation and transformation behaviors during 1-hexene catalytic conversion over ZSM-5 catalysts with tailored Si/Al ratios, and the effects of Si/Al ratio on catalytic deactivation and regeneration property were further elucidated. Structural texture and acidic properties were analyzed by XRD, SEM, N2 adsorption–desorption, NH3-TPD and Py-IR. In-situ FT-IR results reveal that coke deposition proceeds synchronously with the reaction. As the Si/Al ratio increases, deposited coke evolves gradually from polycyclic aromatics to monocyclic aromatic species. Density functional theory calculations further demonstrate that ZSM-5 with a Si/Al ratio of 90–100 achieves a balanced adsorption–desorption energy, promoting reactant activation, accelerating the desorption of coke precursors, and inhibiting severe coking. Benefiting from the suppressed coke accumulation and well-retained recoverable Brønsted acid sites (Si–OH–Al), this optimal catalyst presents excellent regenerability. This work clarifies the acid-dependent coking behavior of ZSM-5, deepens the understanding of deactivation-regeneration principles, and provides reliable guidance for the rational design of high-stability ZSM-5 catalysts toward efficient olefin conversion.

Inverted wide-bandgap perovskite solar cells (PSCs) have drawn significant attention due to their excellent optoelectronic properties, low-cost fabrication processes, and good compatibility with tandem devices. However, the presence of bulk and surface defects limits further improvement in their performance. In this work, a synergistic dual passivation strategy is proposed, using 4-hydroxyphenethylammonium iodide (OH-PEAI) as a bulk additive and 4-trifluoromethylphenethylammonium iodide (CF3-PEAI) as a surface passivation agent. This dual passivation strategy significantly enhances the performance and stability of 1.75 eV perovskite devices by improving crystallization, optimizing energy levels, and passivating defects, achieving a power conversion efficiency (PCE) of 20.22%.

Research on sustainable energy has intensified to reduce greenhouse gas emissions, especially CO2. One promising strategy is the catalytic reduction of CO2 to methanol, and indium oxide (In2O3) has emerged as a highly efficient catalyst, with high turnover rates and selectivity. This work investigates methanol, the end product of CO2 reduction, and its interaction with the In2O3(111) surface. Utilizing an ultrahigh vacuum (UHV) environment, this study combines temperature-programmed desorption (TPD), X-ray photoelectron spectroscopy (XPS), noncontact atomic force microscopy (nc-AFM), scanning tunneling microscopy (STM), and density functional theory (DFT) calculations. The coverages investigated range from 1 to 12 methanol molecules per unit cell. The results are compared to water adsorption on In2O3(111), as the chemical behavior of both molecules is similar in many respects. At low coverage, the adsorption patterns and interactions with the In2O3(111) surface mirror those seen with water, including dissociative and molecular adsorption. The first three methanol molecules dissociate at specific sites within the surface unit cell, while molecular adsorption becomes favored for subsequent molecules at temperatures below 300 K. At the highest coverage (before multilayer adsorption) methanol and water exhibit distinct structures due to their differing hydrogen bonding capabilities.

Fuel consumption for industrial development, SO2 gas emissions are increasing year by year and have become a focal point of air pollution. Membrane separation method photo-responsive materials and MOFs have attracted more and more attention in a variety of fields. This is because the membrane separation method uses less energy and is an uncomplicated process; MOFs have superior gas adsorption capabilities; and the photo-responsive materials are controllable. In this study, mixed matrix membranes are prepared using Uio-66-NH2 and photoresponsive materials CE-Azo-Uio-66 as fillers and Pebax as base membranes. By improving the dissolutiondiffusion mechanism for SO2 gas molecules, SO2/N2 gas separation is accomplished. More channels for the mass transport of SO2 gas through the membrane can be created by MOFs increased porosity and larger specific surface area. Secondly, the SO2 adsorption and dissolution-diffusion mechanism of the mixed matrix membrane are strengthened by the grafted SO2 affinity groups on the MOF. Moreover, Pebax/CE-Azo-Uio-66 membranes is not only significantly more permeation selective than Pebax/Uio-66-NH2 membranes, but also shows photoresponsive characteristic. The SO2 permeability and selectivity of Pebax/CE-Azo-Uio-66 mixed matrix membranes at CE-Azo-Uio-66 content of 20 % are increased by 191 % and 179 %, respectively, compared to pure Pebax membranes. It is also found that the SO2 permeability and SO2/N2 selectivity of the membranes show regularly reversible changes at the UV-Vis photoconversion conditions of Pebax/CE-Azo-Uio-66-20 % membranes, indicating the photo-responsive characteristics of mixed matrix membranes that include Azo groups. The SO2 permeability of the Pebax/CE-Azo-Uio-66 membrane is increased by 1300 Barrer and the SO2/N2 selectivity is increased by 350 when the light source is changed from UV to Vis light, achieving a controlled separation of SO2/N2. Besides, the addition of MOF particles significantly enhances the mechanical properties and stability of the membrane.

AbstractCobalt is an efficient catalyst for Fischer−Tropsch synthesis (FTS) of hydrocarbons from syngas (CO + H2) with enhanced selectivity for long-chain hydrocarbons when promoted by Manganese. However, the molecular scale origin of the enhancement remains unclear. Here we present an experimental and theoretical study using model catalysts consisting of crystalline CoMnOx nanoparticles and thin films, where Co and Mn are mixed at the sub-nm scale. Employing TEM and in-situ X-ray spectroscopies (XRD, APXPS, and XAS), we determine the catalyst’s atomic structure, chemical state, reactive species, and their evolution under FTS conditions. We show the concentration of CHx, the key intermediates, increases rapidly on CoMnOx, while no increase occurs without Mn. DFT simulations reveal that basic O sites in CoMnOx bind hydrogen atoms resulting from H2 dissociation on Co0 sites, making them less available to react with CHx intermediates, thus hindering chain termination reactions, which promotes the formation of long-chain hydrocarbons.

Achieving highly ordered and uniformly covered self-assembled monolayers with optimal packing configuration on textured silicon substrates remains a critical challenge for further improving the efficiency of perovskite/silicon tandem solar cells1-3. Here we design an asymmetric self-assembled monolayer (named as HTL201) featuring an anchoring group and a spacer flanking a carbazole core, serving as a hole-selective layer for perovskite/silicon tandem solar cells. When compared with symmetric self-assembled monolayers with a nitrogen-bonded phosphonic acid group, the HTL201 molecule shows minimized steric hindrance and improved coverage on the transparent conductive oxide recombination layer. The strong coordination interaction between HTL201 and the perovskite film effectively reduces non-radiative recombination at the buried interface. Notably, the optimized energy-level alignment between the perovskite and HTL201, accompanied by an increase in the quasi-Fermi-level splitting value of the perovskite layer, enables an impressive voltage of nearly 2 V for perovskite/silicon tandem solar cells, resulting in a certified power conversion efficiency of up to 34.58% based on a silicon heterojunction solar cell.

Shellac is a natural polymer, primarily composed of lac resin, commonly used as a protective material across various applications. Despite its widespread use, shellac-rich in hydrogen bonds as a natural polymer-has rarely been explored at the molecular level. Herein, we developed a hydrogen-bonded crosslinked biopolymer by combining shellac with two biofriendly H-bond-rich ionic liquids ([Ch][Cur] and Tyr(C-10)(2)NO3) to create a novel biocomposite coating-lCT, which exhibits outstanding surface stability. Remarkably, the tone and timbre of the lCT-coated Bugu remained stable, with frequency variations of <5 Hz over a period of 30 days. Additionally, the lCT-coated Bugu maintained a smooth, bacteria-free surface throughout the month. The roughness of lCT remained below 0.2 mu m over the same period. The water contact angles and the diiodomethane contact angles of lCT-coated surface at different humidities (20%-100%) and temperatures (0 degrees C, 20 degrees C, 40 degrees C) are maintained with minimal variation (<2 degrees) in 30 days. The time-resolved infrared spectrums revealed a rapid film-forming process for lCT, completing within 10 min. Moreover, the DFT calculation results demonstrated that the hydrogen bond competition effect among lac resin, [Ch][Cur], Tyr(C-10)(2)NO3 and H2O promotes surface stability of lCT. This work provides a new perspective for the research and design of H-bond-rich natural polymer materials and their composites.

A strategy of catalytic chemical detection (CCD) with the assistance of a machine learning (ML) approach was proposed and evaluated in this work. In the CCD method, the target analyte acts as the catalyst of the detection reaction rather than traditional reactants. The detection of a typical environmental contaminant-volatile iodine was selected as an example to establish the general routine in designing CCD. One major obstacle lies in the complex of manual selection of detection reaction, especially considering that more than 650,000 related reactions were exhibited in SciFinder database. Traditional workflow is time-consuming and material-consuming; therefore, the ML approach with descriptors directly related to CCD was employed. The reaction of indoles and aromatic aldehydes to bis(indolyl)methanes was screened out with the ML approach. After preliminary experiments, the screened reaction for iodine detection achieved desirable sensitivity, specificity, and recognizability simultaneously. The fabricated sensor devices were practicable for portable detection in real gas samples with a low concentration. This work provides a practical example of chemical analysis based on catalytic strategy and exemplifies the powerful application for the ML method in chemistry through the introduction of original descriptors.

Despite significant advancements in designing covalent organic frameworks (COFs), the directed engineering of them with mesoscopic chirality remains challenging due to the dynamic equilibrium between crystallization kinetics and intermolecular interactions. Herein, we propose a biomimetic chiral supramolecular assembly-mediated (CSAM) strategy for the ambient synthesis of DNA-like bifilar helical covalent organic frameworks (H-COFs) with single-handed chirality. Simultaneously, we revealed the synergistic coupling of directional hydrogen bonding networks and steric confinement effects that governs the chiral supramolecular self-assembly process by integrating spectroscopic characterizations with computational modeling approaches. In this, the modulated supramolecular architectures mediate cooperative functionality between structural templating and catalytic activation during H-COF crystallization, effectively overcoming the inherent limitations of traditional acid-catalyzed and solvothermal approaches. Furthermore, the intrinsic functional groups and dual-helical architecture of H-COFBTCA-TAPB collaboratively facilitate iodine molecule adsorption and stabilization. Notably, the unique π-π stacking mode of the helical skeleton forms donor-acceptor electron transfer channels with iodine molecules. Consequently, the H-COFBTCA-TAPB/I2 achieves a high specific capacity of 176 mAh g-1 at a current density of 0.2 A g-1 and maintains a capacity retention rate of 63% after 10,000 cycles at a high current density of 2.5 A g-1. This work not only advances the fundamental understanding of chiral supramolecular assembly but also provides scalable ways for developing H-COFs with tailored properties.

Precisely determining the oxidation states of metal cations within variable-valence transition metal oxides remains a significant challenge, yet it is crucial for understanding and predicting the properties of these technologically important materials. Iron oxides, in particular, exhibit a remarkable diversity of electronic structures due to the variable valence states of iron (Fe2+ and Fe3+). A quantitative analysis using conventional X-ray photoelectron spectroscopy (XPS) is challenging because of the strong overlap of the Fe 2p XPS peaks from different oxidation states. In this study, we show how this problem can be resolved using Resonant Photoemission Spectroscopy (ResPES), which unambiguously distinguishes Fe oxidation states and spectroscopically estimates the composition ratio of Fe cation valence states in the complex Fe oxides. We demonstrate this in the model case of a FeO2 monolayer film on Pt(111), showing that the FeO2 film consists of an equal mixture of Fe2+ and Fe3+ cations, yielding an average valence of +2.5, contrary to the +3 valence proposed based on density functional theory (DFT).

Two-terminal monolithic perovskite/silicon tandem solar cells demonstrate huge advantages in power conversion efficiency compared with their respective single-junction counterparts1,2. However, suppressing interfacial recombination at the wide-bandgap perovskite/electron transport layer interface, without compromising its superior charge transport performance, remains a substantial challenge for perovskite/silicon tandem cells3,4. By exploiting the nanoscale discretely distributed lithium fluoride ultrathin layer followed by an additional deposition of diammonium diiodide molecule, we have devised a bilayer-intertwined passivation strategy that combines efficient electron extraction with further suppression of non-radiative recombination. We constructed perovskite/silicon tandem devices on a double-textured Czochralski-based silicon heterojunction cell, which featured a mildly textured front surface and a heavily textured rear surface, leading to simultaneously enhanced photocurrent and uncompromised rear passivation. The resulting perovskite/silicon tandem achieved an independently certified stabilized power conversion efficiency of 33.89%, accompanied by an impressive fill factor of 83.0% and an open-circuit voltage of nearly 1.97 V. To the best of our knowledge, this represents the first reported certified efficiency of a two-junction tandem solar cell exceeding the single-junction Shockley-Queisser limit of 33.7%.

Abstract—Cr- and Pt-based catalysts are the most widely used industrial catalysts for propane dehydrogenation (PDH). However, these catalysts still show disadvantages such as environmental toxicity and high economic cost. Cobalt (Co)-based catalysts have become promising candidate catalysts for PDH reactions due to their environmental friendliness and low cost. In this paper, Co-based catalysts are prepared by the impregnation method and precipitation method, respectively. The obtained catalysts all show grape-like nanocrystalline aggregated structures with intercrystallite mesopores and high surface area. This can improve the dispersion of Co species and mass transfer of catalysts. Comparing catalysts prepared by the two methods, the impregnated 1CoZI sample shows smaller CoOx nanoparticle size and higher Co2+/Co3+ ratio than the precipitated 1CoZP sample. Moreover, the impregnated 1CoZI sample shows higher propane conversion and propylene selectivity, which is attributed to the smaller CoOx nanoparticle size and higher content of Co2+ species bonded with zeolite framework. This structure brings higher catalytic activity and stability to the catalyst. Different PDH reaction conditions such as the reaction temperature and propane GHSV are also investigated. Under the optimal PDH reaction conditions (525°C and 4500 h–1), the impregnated 1CoZI shows high propane conversion (32

High-entropy oxides (HEOs) have unveiled a unique frontier in the realm of heterogeneous catalysis, taking advantage of the entropic effect and increased complexities to deliver ultrahigh stability and large tuning capability. However, current HEO synthesis mainly relies on high-temperature annealing approaches affording HEOs possessing no or low surface area, inferior active site exposure efficiency, and low controllability over the structure tuning. The grand challenge lies in producing high-quality HEO catalysts with high active site utilization efficiency, which relies on precision structure engineering, preferably under mild conditions. In this work, an in situ lattice engineering approach was developed to afford a supported HEO catalyst under ambient conditions. The HEO compositions (CuCoFeNiMnOx) were uniformly integrated into the lattice of CeO2 driven by cavitation-induced nucleation being generated via ultrasonication. The as-afforded catalysts were featured by high surface area, atomically dispersed HEO compositions, active redox properties, abundant oxygen vacancies (O-V), antiagglomeration, and high phase stability under harsh conditions. Compared with the ex situ introduction of HEO on the surface, the in situ method provides dual benefits to maintain the dispersity of HEO via entropic and lattice confinement effects. Engineering the complex HEO within the lattice of fluorite-structured CeO2 also yields abundant defects (e.g., O-V) and active metal sites with strong reducing properties (e.g., Ce3+ and Cu+), which greatly improves the activity of the lattice oxygen and tunability of the adsorption behavior of the guest molecules, especially in the presence of impurities (e.g., water and propane). The catalytic performance of the supported HEO catalyst in oxidative procedures surpasses the pure dense phase HEO as well as the ex situ-generated catalysts. The synthesis approach being developed in this work, together with the fundamental understanding in structure evolution and reaction mechanism, showcases a facile pathway under ambient conditions to generate stable catalysts capable of maintaining structural robustness in high-temperature conditions while delivering enhanced catalytic performance.

Back-contact silicon solar cells, valued for their aesthetic appeal because they have no grid lines on the sunny side, find applications in buildings, vehicles and aircraft and enable self-power generation without compromising appearance1-3. Patterning techniques arrange contacts on the shaded side of the silicon wafer, which offers benefits for light incidence as well. However, the patterning process complicates production and results in power loss. We employed lasers to streamline the fabrication of back-contact solar cells and enhance the power-conversion efficiency. Using this approach, we produced a silicon solar cell that exceeded 27% efficiency. Hydrogenated amorphous silicon layers were deposited onto the wafer for surface passivation and to collect light-generated carriers. A dense passivating contact, which differs from conventional technology practice, was developed. Pulsed picosecond lasers operating at different wavelengths were used to create the back-contact patterns. The approach developed is a streamlined process for producing high-performance back-contact silicon solar cells, with a total effective processing time of about one-third that of the emerging mainstream technology. To meet the terawatt demand, we developed indium-less cells at 26.5% efficiency and precious silver-free cells at 26.2% efficiency. Thus, the integration of solar solutions into buildings and transportation is poised to expand with these technological advances. We fabricated silicon heterojunction back-contact solar cells using laser patterning, producing cells that exceeded 27% power-conversion efficiency.

The structural evolution of Cu(111) surfaces in O₂ was studied using in situ scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. The spontaneous formation of Cu₃O clusters was observed on Cu(111) and resolved at an atomic scale. These Cu₃O clusters formed preferentially at step edges, serve as building blocks, which diffuse across neighboring terraces, coalesce into larger clusters, and eventually transform into "5-7" Cu₂O overlayers at room temperature and above. DFT calculations elucidated the selective formation of Cu₃O clusters, originating from Cu detachment near steps and facilitating oxide growth front expansion. A comparison between cluster diffusion and attachment demonstrated the growth dynamics of compact Cu₂O morphologies on terraces. Simulations predicted preferential oxide growth from {100}-oriented steps and favored O diffusion along adjacent {111} facets, explaining the observed triangular fractal morphologies of Cu2O at steps. Our combined STM and DFT approach provides insights into cluster-mediated oxidation dynamics on Cu(111) and could be adapted to understand larger-scale oxidation processes.

Tumor-cell nucleus targeting is highly desired for theragnostic nano-prodrugs (NPDs) to enhance cancer diagnostic and therapeutic efficacy as compared to those targeting the cytoplasm or other intracellular organelles. This study presents a well-designed tumor-cell nucleus targeting theragnostic NPD called 177Lu-YNP@FA that can not only deliver bright upconversion/NIR-II fluorescence but also emit radioactive β-ray radiation for efficient tumor fluorescence localization and radionuclide therapy, based on PEGylated folic acid (FA) decorated NaYF4:Yb/Er@NaYF4 core-shell nanocrystals with radionuclide lutetium-177 labeling. Owing to their unique tumor-cell nucleus targeting capacity, the well-designed 177Lu-YNP@FA NPDs can rapidly target the nuclei of Hela cells within eight hours, thereby allowing for the precise localization of two-hundred-micron-sized metastatic tumors of cervical carcinoma, even in the abdominal cavity of a living mouse model, through NIR-II fluorescence imaging. Importantly, these 177Lu-YNP@FA NPDs exhibit superior tumor accumulation (∼24.6%) and retention (∼7.1 days) compared to the NPDs without tumor-cell nucleus targeting ability. This results in highly efficient anticancer outcomes, both in vitro and in vivo, through a pyroptosis-mediated cell death associated with intracellular β-ray radiation of 177Lu radionuclide. These findings have significant implications for the intelligent design of organelle-specific targeting theranostic NPDs, offering new options for diagnosis and treatment in radiopharmaceutical therapy of cancer.

Electrolysis of seawater for large-scale hydrogen production at industrial current densities signifies a groundbreaking technological leap. However, extant seawater electrolysis encounters challenges rooted in chlorine chemistry and metal deposition. Drawing inspiration from the Moon's protective role for the Earth, we unveil a pioneering satellite-like shielding strategy for dual single-atom catalysis, showcasing an extraordinary performance of 1.66 V at 2,000 mA cm geo- 2 in 6 M KOH and seawater at 80 degrees C, degrees C, coupled with durability exceeding 252 h. Theoretical and experimental evidence confirms that satellite Mn boosts Lewis acid sites of the catalyst, which can strongly bind OH-- and prevent the rising pH of the seawater and Cl-- attack. Synergies between single-atom Mn and Ru further optimize water dissociation barriers and intermediate adsorption energies. This study presents new satellite-like shielding insight for designing highly durable, efficient dual single-atom catalysts with harmful ion resistance, tailored for industrial-grade current densities in alkaline seawater electrolysis.