Constructing 2D/3D bilayer structured all-inorganic perovskites through cation exchange is critically challenging. So far, only a few reports have claimed 2D/3D heterostructure formation via in situ surface reconstruction or cation interdiffusion. Yet, the underlying mechanism remains elusive and a fundamental understanding is still lacking from both thermodynamic and mechanistic perspectives: why and how organic cations displace Cs+ ions. This work presents a detailed mechanistic study encompassing molecular design, experimental validation, and theoretical verification to elucidate the cation exchange mechanism behind this surface reconstruction process. We have specifically developed a novel ammonium iodide salt, namely, DMA-BzAI, by incorporating a strong electron-donating dimethylamino moiety on the para position of the benzene ring in the most commonly used benzylammonium iodide (BzAI). This design aims to decrease the polarization force of the spacer cation toward octahedral inorganic slabs, providing stronger driving forces for ionic substitution. In situ X-ray scattering analysis confirms the dynamic evolution of n = 1 2D perovskites on CsPbI2Br perovskites by treating with DMA-BzAI, contrasting sharply to the case of BzAI. A comprehensive theoretical investigation, including Bader charge analysis, formation energy, and nudged elastic band calculations, further demonstrates that both thermodynamic favorability and low activation barriers allow DMA-BzA+ cations to go through cation exchange reactions to substitute the strongly bound Cs+ ions in the inorganic perovskite lattice, leading to in situ formation of 2D/3D bilayer structure, in alignment with experimental observations. These mechanistic results provide fundamental insights into the cation exchange mechanism behind 2D/3D heterojunction formation in inorganic perovskites, offering rational ligand design principles for future research.
Inorganic-biological hybrid cell factories couple cellular metabolism with inorganic ions and nanomaterials, enabling (i) biosynthesis of functional nanomaterials under mild aqueous conditions and (ii) biohybrid systems in which inorganic components modulate cellular redox, light harvesting and catalysis. This review summarizes nano-bio-interface mechanisms that govern ion uptake, trafficking and intracellular nucleation, and highlights synthetic-biology and metabolic-engineering strategies for improving yield, compositional control and biocompatibility. We survey representative material classes-including semiconductor quantum dots, carbon quantum dots and graphene-family 2D materials derived from microbial feedstocks, rare earth nanophosphors, noble metal nanostructures, and emerging perovskite-type and metal/metalloid materials-and discuss how bio-derived surface chemistries and dynamic interfaces support applications in biosensing, bioimaging, antimicrobial/therapeutic platforms, bioelectronics, and biohybrid production of fuels and chemicals. We conclude by outlining translational constraints relevant to Biomaterials Science, including reproducibility, scale-up, and safety/regulatory drivers that favor toxic-metal-free, stable, and sustainable materials.
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Hyperpolarized (HP) xenon-129 (129Xe) chemical exchange saturation transfer (HyperCEST) provides the opportunity to perform high-sensitivity molecular magnetic resonance imaging (MRI) due to superior signal enhancement. One of the most recently discovered candidates for future development of HyperCEST-active biosensors, resorcinarene trimer methanesulfonate (R3-Noria-MeSO3H), possesses unique complex molecular dynamics resulting in its aggregation around metal cations. To study and understand this behavior of R3-Noria-MeSO3H and its potential interaction with large biological molecules, we conducted time series of UV-vis spectroscopies of different R3-Noria-MeSO3H concentrations in deionized water, phosphate buffer saline, saline, solutions of potassium chloride, choline, and bovine serum albumin (BSA). For the first time, we have acquired R3-Noria-MeSO3H UV-vis spectra and identified the origin of all absorption bands. Our data suggested that Na+ promoted R3-Noria-MeSO3H aggregation the most, while choline hinders it, albeit did not stop it completely. The absorption bands around 353 and 497 nm are the most indicative of the aggregation process and, therefore, may be utilized in future studies of R3-Noria-MeSO3H molecular dynamics. Furthermore, using UV-vis spectroscopy and electrophoretic analysis, we discovered rapid aggregation of R3-Noria-MeSO3H around BSA, forming supramolecular assemblies that persist as dynamic but macroscopically stable populations.
Functional interfaces between magnetic oxides and organic semiconductors have led to a wealth of spin-dependent phenomena, enriching the fundamental understanding of spintronics and offering new routes for next-generation spintronic device engineering. However, modulation of carrier injection at such interfaces, particularly through non-invasive methods, has yet to be thoroughly investigated. This limitation hinders precise control over interfacial charge injection and restricts overall device efficiency. In this work, we construct an LPCMO/P3HT-based organic magnetoresistive diode and demonstrate highly efficient rectification of interfacial carrier transport by exploiting the electronic phase separation (EPS) in the magnetic electrode LPCMO. By tuning the internal EPS of LPCMO, we achieve distinct resistance switching states in the device. Notably, the observed change in device resistance exceeds that of the LPCMO electrode by a factor of 60, revealing a pronounced amplification effect at the interface. This giant modulation originates from the EPS-induced Fermi level shift in LPCMO, which reduces the interfacial energy barrier and significantly enhances carrier injection efficiency across the oxide/organic semiconductor interface. Our findings present a new strategy for precise and in situ control of carrier injection processes, which may further advance both the scientific and technological frontiers of organic spintronics.
Molecular-scale integration of non-natural functional components into living systems for precise manipulation, monitoring, and enhancement of organisms remains a great challenge. Here, we achieved the geneticable synthesis of functional inorganic nanomaterials with molecular-level spatial precision within live mammalian cells. By genetically encoding a cysteine-rich protein tag named 1DFS, and tuning its intracellular inherent metabolic pathways, organic molecules can be precisely synergized with inorganic molecules at a specific site of the protein of interest within live cells to grow a single inorganic semiconductor nanocrystal-specifically quantum dot (QD). This, in turn, endows the protein with unique fluorescent functions for precise and stable protein labeling even after multiple cell passages. This approach is flexible and universal, and QD can not only integrate into the specific protein in live cells but also synchronously grow on the delicate viral nucleoprotein (NP) during the natural replication and assembly of virions in the host cells. The labeled NPs then accurately assemble into viral ribonucleoproteins deep inside virions, resulting in fluorescent virions with full infectivity that exceeds capabilities of conventional genetic manipulation. This work provides a programmable platform for geneticable growth of inorganic nanomaterials at specific molecular sites, opening a new frontier in precise inorganic-enabled synthetic biology.
Quantum dots (QDs), a remarkable inorganic semiconductor nanocrystal capable of converting light energy into electrical, chemical, thermal, and other forms of energy, can be used to create super living systems through their fusion with cells, which hold tremendous potential for biomedical applications. Although considerable efforts have been devoted to delivering in vitro synthesized QDs into cells via endocytosis or electroporation, these approaches often suffer from poor biocompatibility, uncontrolled uptake pathways, and nonspecific intracellular interactions. Moreover, to satisfy the stringent demands of biological environments, QDs produced through conventional synthetic routes typically require extensive postsynthetic treatments, such as phase transfer into aqueous media and surface functionalization, which can irreversibly disrupt their surface structure and substantially compromise their photoluminescence quantum yield and photostability. Consequently, the exceptional optical properties of QDs are difficult to fully maintain when applied in physiological environments. Live-cell synthesis of QDs provides an innovative strategy to overcome these intrinsic limitations. By harnessing the intracellular spatiotemporally organized biochemical metabolic networks, this strategy enables the controlled synthesis of QDs while synchronously accomplishing in situ labeling. The resulting QDs are naturally coated with endogenous biomolecules and can be directed to form at specific subcellular locations, which inherently ensures high biocompatibility and precise integration with local cellular structures. This method establishes a robust foundation for in situ labeling of delicate cellular components and opens new avenues for high-fidelity acquisition of dynamic information within complex biological processes. Moreover, this flexible and universal strategy to fuse inorganic nanocrystals with live cells can endow organisms with enhanced or novel functionalities, holding significant promise for diverse applications in the fields of biomedicine and energy conversion. In this Account, we systematically summarize our efforts in the field of the live-cell synthesis of QDs. Our discussion encompasses the development of the "space-time-coupled" synthetic strategy, the elucidation of the key molecular mechanisms underlying the intracellular synthesis of QDs, and the diverse applications of this technique in pathogen detection, microvesicle labeling, site-specific protein labeling, and in vivo tumor imaging. Furthermore, inspired by the live-cell synthetic pathways, we introduce a cell-free "quasi-biosynthesis" system that enables controllable synthesis of near-infrared Ag2Se QDs and supports surface-chemistry-based strategies for precise modulation of photoluminescence properties. Finally, we outline the key challenges and future opportunities in this field, emphasizing that the synergistic integration of genetic engineering with precision materials science will profoundly advance the intracellular synthesis of nanocrystals and unlock new possibilities in high-precision sensing, dynamic regulation, and functional augmentation of biological systems. We believe that, with a deepened understanding of the synthetic mechanisms and continued innovation in synthetic methods, the spatial precision, operational reliability, and functional integration of QDs within living systems will be significantly enhanced, thereby providing a powerful toolkit for revealing biological mechanisms and advancing precise disease diagnosis and treatment strategies.
ConspectusThe innovative exploration of non-fullerene acceptors (NFAs) such as ITIC, Y6, and others, has boosted the power conversion efficiencies (PCEs) of organic solar cells (OSCs) surpassing 21%. However, organic photovoltaics still suffer from significant efficiency gaps compared to inorganic photovoltaics, particularly in open-circuit voltage under similar bandgaps. This notable disparity is largely driven by the stark difference in nonradiative recombination energy losses: OSCs typically incur losses exceeding 0.2 eV, whereas their inorganic counterparts suffer only minimal losses, ranging from a mere 0.03 to 0.04 eV. This insurmountable nonradiative recombination is closely associated with some intrinsic features of organic photovoltaic light-harvesting materials: relatively flexible molecular frameworks, loose and disordered molecular aggregates, large exciton binding energies, etc. Therefore, a multiscale regulation spanning single-molecular properties and aggregation behaviors in further molecular design is required, if a remarkable PCE improvement is expected.In this Account, we first present a brief review of the development of electron acceptor materials, with a focus on analyzing the prominent merits of current high-efficiency acceptor molecular skeletons (especially Y6 analogs) in terms of intermolecular packing modes, photodynamic, etc. Meanwhile, great challenges for further material design also arises from the quite limited structural optimization room for Y-series backbones. In order to break through the dilemma of molecular design, we developed CH-series NFAs with multi-functionalized central units and an "acceptor-donor-acceptor" architecture. Subsequently, a systematic discussion about CH-series NFAs will be made to reveal their advantages in (1) inducing a directional transformation of molecular packing mode toward a more favorable one, through multiple intermolecular weak interactions such as fluorine-hydrogen/sulfur/π bonds, thus rendering multidimensional long-range ordered molecular stacking to minimize energy loss pathways in OSCs; (2) breaking through the limitations of traditional dimeric/trimeric/polymeric acceptor design by pioneering the construction of relatively rigid central-units-linked dimeric/trimeric NFAs with multiple free terminals to enhance intermolecular packings; (3) proposing a novel "functional reconfiguration" strategy for the central units, aiming to explore new photoelectric conversion mechanisms in organic photovoltaic materials.Thus far, CH-series NFAs based binary OSCs have achieved the highest PCE of approaching 21%, ranking among the best NFAs. If further considering their great structural modification possibilities, CH-series NFAs hold exceptional promise as a versatile platform for developing OSCs with record-breaking PCEs. Therefore, we further propose some perspectives for CH-series NFAs, for example, more precise structural and packing optimization to reduce exciton binding energies and improve molecular packing ordering; further in-depth exploration of a "functional reconfiguration" strategy to apply new photoelectric conversion mechanisms, such as triplet excitons, singlet fission, etc.; extending the absorption edge of NFAs to near-infrared II region to harvest more low-energy photons, especially for tandem OSCs. These strategies may have the potential to overcome the critical challenge existing in OSCs and shrink the PCE gap comparing to inorganic platforms.
Circularly polarized luminescence (CPL) in the ultraviolet B (UVB) region holds great potential applications in asymmetric catalysis, enantioselective polymerization, and polarization-based optical anticounterfeiting and information encryption. However, to date, the CPL materials in the UVB region remain unexplored. In this study, the first chiral gadolinium-based organic-inorganic hybrid metal halides, (R/S-C3H7NF3)3GdCl6 (R/S-3F-Gd), were constructed, which exhibit efficient CPL in the UVB region. Owing to the unique 4f-4f transition of Gd3+ ions, R/S-3F-Gd shows a high photoluminescent quantum yield of 18%, a narrow full width at half maximum (∼3 nm) and a ultralong photoluminescence lifetime (∼6.6 ms). Additionally, their CPL can be further tuned by applying the external magnetic field. Then the light-emitting diode (LED) chips coated with R- or S-3F-Gd were also fabricated, which exhibit high dissymmetry factor of + 9.1 × 10-3 and -8.2 × 10-3, further demonstrate their potential as circularly polarized light source in the UVB region. Our work offers a novel strategy for designing the chiral luminescent materials with efficient CPL response in the UVB region and broadens the family of chiral organic-inorganic hybrid rare-earth halides.
Since 2007, recurrent green tide blooms caused by Ulva prolifera have been observed in the Yellow Sea of China; however, their temporal window and spatial scale remain unknown. This study constructed a downscaling numerical reconstruction method associated with the spatiotemporal correspondence of green tides to elucidate the key processes underlying U. prolifera blooms. Based on spatiotemporal downscaling analysis, green tide block drift paths and the growth extinction processes of U. prolifera in the Yellow Sea from 2008 to 2021 were identified. U. prolifera growth extinction processes were reproduced well using a three-box Nutrient-U. prolifera-Debris (NUD) model. U. prolifera green tides exhibited gradual earlier onset characteristics, accompanied by an increase in global temperatures. Dissolved inorganic nitrogen (DIN) and dissolved inorganic phosphorus (DIP) pools regulate the scale of green tides, exhibiting significantly positive correlations with DIN (p < 0.01) and DIP loads (p < 0.01) in molar amounts. These results offer further insights into the mechanisms regulating U. prolifera green tide blooms in the context of global warming and coastal eutrophication.
Ion exchange chromatography (IEC) and mixed-mode chromatography are highly effective for the separation of polar and ionic compounds, including inorganic ions, proteins, peptides, pharmaceuticals, nucleotides, and organic acids, owing to their unique ion exchange or mixed-mode retention mechanisms. As the core component of chromatographic system, the stationary phase directly determines separation selectivity and column efficiency. Therefore, the rational design and development of novel stationary phases remain a focal in modern separation science. In response to the increasing complexity of sample matrices, recent advances have driven the evolution of high‑performance IEC stationary phases that are shifting from a single ion exchange mechanism toward sophisticated multifunctional designs. To better elucidate the critical structure-performance relationships governing the chromatographic behavior, this review provides a comprehensive overview of the evolution of substrates and surface modification strategies (e.g., click chemistry, controlled radical polymerization, and hyperbranched modification) employed in preparing of modern stationary phases over the past decade. Furthermore, this review concludes with a critical discussion of the current challenges and future development trends of chromatographic packing materials.
Traditional sulfoxide synthesis often relies on toxic oxidants and harsh conditions. Photocatalytic oxidation using inorganic semiconductors provides a greener approach but is limited by low catalytic efficiency. Herein, we developed a heterostructure catalyst enriched with cadmium vacancies (denoted as CdvSx/Ti3CN). The optimized CdvS4/Ti3CN exhibited a high sulfoxide production rate of 21.85 mmol·gcat -1·h-1, outperforming most reported catalytic systems. Comprehensive characterization revealed that sulfur dosage was precisely tuned during synthesis to generate abundant cadmium vacancies and expose active crystal facets. In particular, the presence of cadmium vacancies enhances substrate adsorption via unsaturated coordination sites, lowers the energy barrier for bond activation, and promotes the activation of O2 into superoxide radicals. Moreover, Ti3CN further facilitates photogenerated electron transfer and enhances superoxide radical concentration by enabling favorable band alignment with CdS. In addition, the catalyst demonstrates excellent substrate compatibility and recyclability. This work offers a new approach for improving the performance of CdS-based inorganic semiconductor catalysts in sulfoxide synthesis through Cd defect engineering.
Dimensionality engineering has been proven as a pivotal approach to the modulation of chemical and electronic structures of organic-inorganic hybrid metal halides (OIHMHs) for advanced optoelectronic applications. However, prevailing methods primarily rely on altering chemical composition, which limits the precision and predictability of fine-tuning. Herein, we propose a new conformational modulation strategy to direct the self-assembly of chiral OIHMHs without changing their chemical compositions. By steering the conformation of the cyclic chiral cation, R/S-2-methylpyrrolidinium, we achieve precise control over the connectivity and dimensionality of inorganic units. Designing mixed conformational systems by introducing axial-conformation into equatorial-conformation structures successfully enables efficient chiral amplification and enhances linear and nonlinear chiroptical responses. The resulting OIHMHs exhibit a photoluminescence quantum yield exceeding 86%, high anisotropy factors in linear and nonlinear optical circular dichroism, circularly polarized luminescence, and an enhanced second-harmonic generation intensity by two orders of magnitude. Such a simultaneous enhancement in both linear and nonlinear chiroptical properties arises from the modulation of steric hindrance and electronic structure in organic cations mediated by molecular conformation. This work highlights the contribution of conformational modulation to structural design and performance optimization, broadening the prospects for precise modulation of high-performance optoelectronic functions in chiral OIHMHs.
Ruddlesden-Popper perovskites are promising photovoltaic materials because their enhanced structural and environmental stability relative to their three-dimensional counterparts. However, weak interactions between organic spacer and the adjacent inorganic framework often undermine structural stability and impede charge transport. Here, we demonstrate that the hydrazide-based spacer, thiophene-2-hydrazide (ThCH), unexpectedly induces strong interlayer orbital coupling in 2D RP perovskites despite its monocyclic aromatic structure. It is found that the hydrazide group extends electronic conjugation and promotes orbital hybridization between ThCH and the adjacent inorganic framework, a phenomenon not observed in conventional single-ring aromatic spacers. This effect is further verified by benzo hydrazide, which shares a similar structural motif. Beyond promoting electronic coupling, the hydrazide functionality enhances film formation, yielding enhanced crystallization uniformity and facilitating efficient charge transport. Consequently, ThCH-based RP perovskite (nominal n = 4) devices achieve record efficiencies of 22.41% (certified 21.74%, 0.074 cm2) for small-area devices and 20.74% (certified 20.01%, 1.015 cm2) for large-area devices, the highest reported for quasi-2D RP PSCs. This study establishes a molecular design strategy that uses multifunctional hydrazide modules to overcome the electronic insulation of single-ring aromatic spacers, enabling robust and efficient RP PSCs.
All-solid-state lithium batteries (ASSLBs) offer improved energy density and safety over traditional liquid-electrolyte systems. However, their practical use is limited by the rigidity of inorganic lithium superionic conductors, which require impractically high stack pressures (>50 MPa) to maintain close solid-solid contacts during cycling. We introduce the idea of incorporating nonmetal-chlorine chemical bonds into the conductive network to make rigid conductors more flexible. Because nonmetal-chlorine chemical bonds (e.g., P-Cl, Si-Cl) exhibit low bond dissociation energies, they can undergo facile rotation and torsion, thereby facilitating Li+ migration and framework deformability. A liquid SiCl4 activation method is developed to introduce these chemical bonds, yielding a soft superionic conductor, Li3P0.58Si1.25Zr1.78Cl10.86O3.58. This material shows a high room-temperature Li+ conductivity of 4.55 mS cm-1 and a low Young's modulus of 2.09 GPa. This combination enables over 3000 cycles of ultrahigh-nickel cathode LiNi0.92Co0.05Mn0.03O2 at a high current density of 3 mA cm-2, and even allows for stable operation of ASSLBs with no capacity decay after 300 cycles under a low stack pressure of 5 MPa, much lower than the usual 50 MPa needed for most inorganic superionic conductors. Additionally, this chemical-bond-tuning method works with various nonmetal centers (P, Si, C, S), providing a flexible strategy for designing deformable superionic conductors suitable for low-pressure ASSLBs.
Bacterial infections of the central nervous system (CNS) remain life-threatening disorders with high mortality, largely due to limited drug permeability across the blood-brain barrier and dose-dependent toxicities of conventional antimicrobials. Here, we report a two-dimensional magnesene nanosheet generated by low-temperature ultrasound exfoliation of magnesium crystals via selective activation of dislocations and slip systems. The resulting material releases abundant Mg2+ ions at the bacterial interface, inducing localized magnesium overload and mechanical disruption of membrane integrity. This dual physicochemical stress impairs membrane-associated transport in Staphylococcus aureus and Escherichia coli, ultimately triggering rapid bactericidal effects. Magnesene exhibits potent and broad-spectrum antimicrobial activity in vitro, and analysis of clinical cerebrospinal fluid samples from CNS-infected patients further confirms its translational potential in reducing microbial burden. In rat CNS infection models, magnesene markedly suppresses bacterial proliferation and attenuates neuroinflammation. As a novel inorganic nanomedicine, magnesene offers a promising strategy for combating refractory CNS infections and may broaden therapeutic options against diverse microbial pathogens.
Growing single-crystal two-dimensional covalent organic frameworks (2D COFs) for precise atomic-level structural determination presents a formidable yet crucial challenge. Here, we develop a topology derivation strategy to design and synthesize five single-crystal 2D binodal [4 + 4] COFs, transforming the parent edge-transitive sql topology network into two distinct derivative networks with pseudo-bex and pseudo-hcb topologies by strategically varying the symmetry of the organic building blocks. Their precise structures are unambiguously resolved by three-dimensional electron diffraction with a resolution of up to 0.90 Å, and all non-hydrogen atoms are directly located. A systematic structure analysis reveals that the imine bond orientation dictates intralayer arrangements, yielding both planar and unconventional wavy layers. We also observe that all COFs prefer an inclined, staggered AB stacking pattern, with layers inclined along three distinct directions, breaking the diagram that [4 + 4] COFs exhibit AA stacking. Furthermore, we demonstrate that, compared with traditional low-crystallinity powdery phases, single-crystal COFs significantly boost C2H2/CO2 separation performance, underscoring the critical importance of constructing advanced materials with highly ordered structures. Atomically precise structure determination provides a definitive foundation for linking structural order to emergent properties in 2D COFs, pushing the boundaries of reticular chemistry.
A nanocrystal's cross-section for stimulated emission is regularly hidden in ultrafast transient absorption spectra owing to overlapping excited-state absorption and ground-state bleaching. In a recent study, a novel three-pulse femtosecond spectroscopic method, coined the 'spectator exciton' approach, was used to overcome this in quantum-confined CsPbBr3 nanocrystals. Results proved that stimulated emission takes place already in the single-exciton state, but with a probability roughly an order of magnitude weaker than band-edge absorption. Only in bi-excitons does stimulated emission overpower absorption, providing net optical gain. Prompted by literature reports that replacing caesium with organic ammonium cations and shifting their morphology from cubes to spheres alters band edge level spacing and ordering, we measured stimulated emission in the same way in quantum-confined spheroidal FAPbBr3 nanodots of similar dimensions. Results prove that at room temperature, the unusual ratio between a single-exciton bleach and its stimulated emission cross-section observed in CsPbBr3 nanodots is unchanged by cation exchange and morphological alterations. The robustness of the measured cross-section ratios to these structural modifications stresses their generality and the importance of clarifying the underlying mechanisms. This article is part of the discussion meeting issue 'Excitonic frontiers'.
17β-Estradiol (E2), a typical endocrine-disrupting chemical, is widely detected in various aquatic environments, including rivers, lakes, groundwater, estuaries, and coastal waters, posing significant ecological and health risks. Photodegradation is a key pathway for the transformation and removal of E2 from aquatic systems. This study investigated the effects of dissolved organic matter (DOM) from different sources and common inorganic anions (Cl- and NO3-) on E2 photodegradation under simulated solar irradiation. The results indicated that the excited triplet state of DOM (3DOM*), generated upon light absorption, was the key reactive species driving E2 photodegradation. Among the DOM sources examined, humic acid exhibited the strongest promotive effect on E2 photodegradation. Correlation analysis confirmed that terrestrial humic-like components within seawater DOM were the primary contributors to 3DOM* formation. Seawater DOM from nearshore areas exhibited higher steady-state concentrations of 3DOM* owing to greater terrestrial input. Both Cl- and NO3- effectively accelerated E2 photodegradation, and the E2 degradation rate increased with their concentrations. In contrast, the coexistence of Cl-, NO3-, and DOM inhibited E2 photodegradation. In DOM-dominated systems, the main transformation pathways of E2 involved oxidation and hydrolysis reactions on the phenolic ring. This study elucidates the effects of DOM source and water chemical composition on E2 photodegradation, which is crucial for accurately predicting its environmental fate and ecological risks. Moreover, the findings provide valuable insights into the photochemical transformation of other emerging organic contaminants.
π-Extended conjugation offers the opportunity to unveil new frontiers in materials, coupling redox activity with tunable photophysical properties. Here, we report a new family of π-conjugated salen ligands bearing phenylene bridges and tunable substituents, together with their corresponding boron difluoride complexes. Owing to the extended π-delocalization, these new compounds show promising results in electrochemical CO2 reduction to CO, achieving a remarkable Faradaic efficiency for an organocatalyst (up to 56%). Electrochemical, spectroscopic, and computational analyses support a ligand-centered mechanism in which single-electron reduction activates the framework for CO2 binding at the imine nitrogen, forming an N-bound CO2H intermediate. Beyond electrocatalysis, coordination to boron rigidifies the π-framework, producing emissive boron-salphen complexes with large Stokes shifts (>7000 cm- 1). These complexes function as efficient photosensitizers for singlet-oxygen generation, enabling mild oxidative cleavage of alkenes under blue-light irradiation. This work demonstrates that π-extension transforms the traditional salphen framework into a redox-active engine for small-molecule activation, bypassing the need for transition metals in CO2 electroreduction while simultaneously unlocking good photosensitizing capabilities.