ChemSusChem最新文献

It remains a significant challenge for a photocatalyst to achieve a broad light response, effective O2 adsorption and long photogenerated carrier lifetime in the catalytic reaction. Herein, we design a plasmonic Bi@Vo-Bi2O3 core@shell heterojunction via the hydrothermal method and demonstrate the presence of surface oxygen vacancies identified with electron spin resonance (EPR). Importantly, O2 temperature programmed desorption (O2-TPD) in combination with UV/Vis diffuse reflectance spectra (UV/Vis DRS) revealed the introduction of plasmonic Bi as the core of Bi@Vo-Bi2O3 effectively promotes O2 adsorption by capturing electrons from the defect states and broad the light absorption response range, which synergistically promote catalytic activity on O2 reduction to H2O2 production, pollutant degradation and antibacterial performance in pure water without sacrificial agent. Additionally, the Schottky barrier interface in integrated Bi@Vo-Bi2O3 prevents the excited electrons from recombining with the holes. Furthermore, it was proven that 1O2 played a prominent role in the degradation of Methylene blue, as confirmed by scavenger experiments and detailed experimental characterizations. This work's insights into the photocatalysis mechanism may guide the development of new photocatalysts for enhancing photocatalytic performance.

Numerous methods have been developed to address gaseous formaldehyde pollution, but most of them cannot be applied directly to eliminate the pollution of formaldehyde in aqueous solutions. Formaldehyde in aqueous solutions can be leached from formaldehyde-containing solid materials (e.g., food, wood, clothes, resins) and absorbed from gaseous formaldehyde by water. Here we developed an enzymatic cleanup technique - the reconstitution of an enzyme cocktail consisting of three coenzyme-free oxidoreductases (i.e., formaldehyde dismutase, methanol oxidase, and formate oxidase) and catalase for the complete oxidation of formaldehyde. This enzyme cocktail catalyzed the reaction of formaldehyde and ambient dioxygen into carbon dioxide (CO2) and water, which was demonstrated by the stable isotope tracer technique. Significant levels of formaldehyde were detected from aqueous solutions leached from the squid, pomfret, fabric, and curtain in the market. When this enzyme cocktail was applied to treat the leachates of contaminated samples above, formaldehyde was eliminated with degradation ratios of up to 100%. This enzymatic cleanup technique, featuring excellent biosafety (for example, degradable catalysts and non-immunogenicity), independence from light, high degradation ratios, and no special equipment required, could be widely used to treat contaminated food, drinking water, and formaldehyde-containing leachate.

The kinetics matching of CO₂ reduction and H₂O oxidation is required in sacrificial agent-free photocatalytic CO₂ reduction. It indicates that the modification engineering on photocatalytic H₂O oxidation half-reaction except that on photocatalytic CO₂ reduction half-reaction should be equally paid attention, which has been easily ignored in most of the literatures. Herein, Ni single atoms (NiSAs) and nanoparticles (NiNPs) co-loaded Ti-MOF-derived TiO₂ having a flower-like nanosphere microstructure (NiSAs@NPs/TC) was developed for synchronous design of well-defined redox active sites of photocatalytic CO₂ reduction and H₂O oxidation. It was verified that NiNPs and NiSAs as the active sites of CO₂ reduction and H₂O oxidation, respectively, synergically accelerated photocatalytic redox reactions and enhanced separation of photo-generated carriers. NiSAs@NPs/TC showed a remarkable photocatalytic CO₂-reduction performance (CO and CH₄ products: 35.60 and 3.41 μmol g^-1 h^-1, respectively) in H₂O vapour which was at the advanced level in published relevant studies. Furthermore, the reaction process of CO₂ reduction on NiNPs was proposed based on the key intermediates capture of CO and CH₄ production in photocatalytic CO₂ reduction by in situ analysis.

Green, low-carbon, and efficient chemical conversions are crucial for the sustainable development of modern society. Enzyme-photocoupled catalytic systems (EPCS), which mimic natural photosynthesis, utilize solar energy to drive biochemical reactions, providing emergent opportunities to address the limitations of traditional photocatalytic systems. However, the integration and compatibility of photocatalysis and biocatalysis present challenges in designing highly efficient and stable EPCS. Zirconium-based metal-organic frameworks (Zr-MOFs) with outstanding chemical and thermal stability, large surface area, and tunable pore size are ideal candidates for supporting enzymes and enhancing photocatalytic processes. This review aims to integrate Zr-MOFs with EPCS to further promote the development of EPCS. First, an overview of the basic components and design principles of EPCS is provided, highlighting the importance of the unique properties of Zr-MOFs. After that, three different strategies for combining enzymes with Zr-MOFs are summarized and their respective advantages are evaluated. Finally, the development opportunities and some problems to be solved in this field are proposed.

Commodity polystyrene from styrofoam food boxes was chemically transformed into redox-active organic polymers via a two-step functionalization sequence. In the first step, controlled chloromethylation of the pendent phenyl rings was used to functionalize 30-50 % of the polymer chain. The degree of functionalization could be tuned by simply varying the reaction time (1-3 h). Next, phenothiazine or nitroxide radical moieties were introduced via nucleophilic displacement of the benzylic chlorides to afford polymers with redox-active pendent sidechains. These phenothiazine and TEMPO-functionalized polymers were then characterized electrochemically to demonstrate their redox properties and evaluate their performance as battery electrodes. Overall, this process serves as proof-of-concept for the rapid conversion of consumer-grade styrofoam into redox-active polymers with the potential to serve as metal-free electrodes in organic batteries.

This study introduces an asymmetric self-assembled monolayers (SAMs) architecture, ((5H-Diindolo[3,2-a:3',2'-c]carbazole-5,10,15-triyl)tris(propane-3,1-diyl))triphosphonic acid (3PATAT-C3), designed to advance interfacial engineering in perovskite photoelectric devices. The molecular design integrates three phosphonic acid anchoring groups, enabling robust bonding with the substrate to enhance sustainability. Strategically positioned Lewis basic oxygen and sulfur heteroatoms drive synergistic interactions, addressing the limitations of conventional SAMs by optimizing interfacial contact and surface coverage. The face-on orientation of the molecules promotes energy alignment (work function: 5.18 eV) and superior crystallization (grain size: 0.784±0.315 μm). These features collectively improve moisture resistance and charge transport efficiency. Performance metrics demonstrate significant enhancements, including a power conversion efficiency of 21.74 %, a reduction in dark current density (8.93×10^-9 A/cm²), and a shot noise-limited detectivity of 1.01×10¹³ Jones. By applying multi-bridging strategies and sustainable chemistry principles, this work offers a paradigm shift for designing high-performance optoelectronic devices.

Pressure-sensitive adhesives (PSAs) are polymers with tunable viscoelastic properties, primarily determined by the structural configuration of their polymer chains. In this study, we report the development of a CO₂-based poly(carbonate-ether) for use in PSAs applications, synthesized via the copolymerization of CO₂ and propylene oxide. The viscoelastic properties of the resulting polymer can be precisely modulated by varying its molecular weight (M_n) and carbonate unit (CU) content, yielding excellent comprehensive performance without the need for additional tackifiers or additives. Notably, PCE9, with a M_n of 90 kg/mol and a CU content of 50 %, exhibited optimal performance, achieving a 180° peel strength of 5.70 N/cm with adhesive failure upon peel-off, and maintaining static shear adhesion for up to 2760 minutes. This development of CO₂-based copolymers for PSAs applications not only represents a novel approach to the utilization of CO₂-derived materials but also provides an innovative pathway for the sustainable advancement of the PSAs industry.

The most widespread procedure to measure the antioxidant activity of lignin is via the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. So far, different experimental procedures (i. e., different solvent, time, etc.) have been used to implement the DPPH methodology without estimating the effect of such modifications on the experimental procedure. To overcome this issue, the impact of the solvent, the time, and the type of substrate on the evaluation of the antioxidant activity (AoA) of lignin via the DPPH assay was investigated in this work. We found that multiple different parameters affect the evaluation of the AoA of lignin: i) the stability of the DPPH radical and the lignin solubility in a given solvent; ii) the importance of reaching steady state (the effect of time); iii) the background noise associated with lignin absorbance at λ=515 nm (used to monitor the DPPH radical scavenging); iv) lignin structure; v) providing a normalized radical scavenging index (nRSI); vi) comparing nRSI vs. inhibition percentage (IP) values. Overall, our investigation allowed us to provide guidelines on how to perform the DPPH assay for a more reliable evaluation of lignin AoA.

The nitrogen cycle exposes humans to significant risks due to the substantial rise in nitrate levels in global groundwater. The electrocatalytic reduction of nitrate to ammonia (eNRA) offers a dual benefit: mitigating nitrate accumulation in water bodies and fostering the development of hydrogen energy. In this review, we examine recent progress in eNRA research, focusing on reaction pathways/mechanisms, performance testing, and catalysts development. We begin with an overview of recent applications of metallic and nonmetallic catalysts in eNRA. Next, we discuss three extensively studied reaction pathways, detailing their identification methods and processes. From a catalyst design perspective, we review advancements in metallic compound catalysts, highlighting their advantages and limitations. Finally, we provide insights into the further directions and challenges in this field. This review aims to serve as a valuable resource for designing advanced cathodic electrocatalysts, driving the sustainable utilization and production of renewable resources.

This study presents a novel approach for fabricating high-performance pressure-sensitive adhesives (PSAs) using spruce tree lignin. Through a lignin-first strategy, lignin is selectively depolymerized into 4-propanol-tethered guaiacol, followed by amination, acrylamidation, and copolymerization with n-butyl acrylate (BA) to generate polymeric materials. The resulting lignin-derived PSAs exhibit excellent mechanical properties, achieving a peel strength of up to 4.4 N cm^-1 and a tack strength of up to 3.9 N cm^-1, surpassing those of several commercial products. This work provides a unique pathway to sustainable, high-performance PSA solutions to meet growing industrial demand.