Can-Zhong Lu

Electrocatalytic CO2 reduction (E-CO2RR) powered by renewable energy is vital for carbon cycling and carbon neutrality. Cu-based catalysts uniquely produce multi-carbon (C2+) products, yet the interfacial water microenvironment and reaction kinetics remain poorly understood. This work fabricates hydrophobic HY-Cu2O (100) catalysts by self-assembling octadecanethiol on cubic (100)-faced Cu2O nanoparticles to tune interfacial water. Integrated characterizations, electrochemistry, and in situ Attenuated Total Reflection Surface-Enhanced Infrared Absorption Spectroscopy (ATR-SEIRAS) reveal how hydrophobicity regulates E-CO2RR performance. Hydrophilic/hydrophobic contact-angle measurements reveal that the surface wetting angle changes from 46.1° (hydrophilic) to 133.5° (hydrophobic). X-ray diffraction (XRD) confirms that the crystal structure remains unchanged. X-ray photoelectron spectroscopy (XPS) results demonstrate that the Cu-S coordination environment of the material is modified. Further inference suggests that the formation of Cu-S bonds verifies the successful functional grafting of octadecyl chains onto the Cu2O (100) surface, which alters the surface hydrophilicity/hydrophobicity without inducing any variation in the crystal structure. In 1 M KOH flow cells, HY-Cu2O delivers 45.2% Faradaic efficiency for ethylene at -250 mA∙cm-2 and suppresses parasitic Hydrogen Evolution Reaction (HER), far exceeding bare Cu2O. In situ spectra and theory verify that hydrophobic interfaces accumulate K+-bound free water, disrupt interfacial hydrogen bonds, accelerate *CO protonation, and boost C-C coupling for C2+ intermediates. Higher surface CO coverage further kinetically favors C2+ formation. This work establishes an effective hydrophobic modification approach, clarifies the central role of interfacial water in ethylene selectivity, and offers guidance for the design of advanced CO2RR catalysts.

Cu(I) complexes have attracted considerable attention due to their abundance, low cost, and distinctive photophysical properties, making them promising candidates for thermally activated delayed fluorescence (TADF) applications. We synthesized two mononuclear Cu(I) halide complexes using 2-ethylpyrazine and the diphosphine 4,5-bis(diphenylphosphino)-9,9-dimethylxanthene (Xantphos). At room temperature, Complex 1 exhibits yellow emission at 575 nm with a photoluminescence quantum yield (PLQY) of 68%, while Complex 2 exhibits orange-red emission at 612 nm with a PLQY of 28%. Temperature-dependent luminescence measurements combined with decay lifetimes demonstrate that both complexes exhibit TADF characteristics with small singlet–triplet energy gaps (ΔEST) of 0.09 eV for 1 and 0.07 eV for 2. Theoretical calculations reveal that the emission primarily originates from mixed metal-to-ligand (MLCT), halide-to-ligand (XLCT), and ligand-to-ligand (LLCT) charge-transfer transitions. The stronger heavy-atom effect of iodine in 1 enhances spin–orbit coupling (SOC), promoting reverse intersystem crossing (RISC), while its more rigid coordination environment suppresses nonradiative decay. Conversely, the red-shifted emission of 2 increases nonradiative decay via the energy-gap law. These findings highlight that TADF efficiency is governed by the balance between SOC-facilitated RISC and nonradiative decay suppression, rather than ΔEST alone, providing insights for designing high-performance, low-cost luminescent materials.

Cu( i ) complexes have attracted considerable attention in optoelectronics due to their low cost, excellent structural tunability, and unique photophysical properties.

The strategic incorporation of open‐shell radicals into covalent organic frameworks (COFs) represents a promising yet underexplored avenue for designing metal‐free oxygen reduction reaction (ORR) electrocatalysts. Moving beyond conventional closed‐shell linker engineering, we present a one‐step multivariate synthesis to precisely install 2,2,6,6‐tetramethylpiperidine‐1‐oxyl (TEMPO) radicals within a crystalline COF skeleton. The resulting radical‐embedded TPET‐TEMPO COF exhibits superior four‐electron (4e ⁻ ) ORR activity, evidenced by an electron transfer number of 3.95 and a minimal H ₂ O ₂ yield of 8.8% (at 0.25 V vs. RHE), considerably outperforming the radical‐free TPET analogue. Mechanistic studies using density functional theory (DFT) calculations attribute this performance to the TEMPO radicals functioning as an intrinsic electron shuttle, which lowers the activation barriers for ORR, in agreement with experimental observations. Practical viability of TPET‐TEMPO is demonstrated in a rechargeable zinc‐air battery (ZAB), where TPET‐TEMPO as the cathode catalyst delivers a peak power density of 148.4 mW cm ⁻² . This work highlights the critical role of radical motifs as active vertices and outlines a facile blueprint for constructing radical‐bearing COFs for efficient energy applications.

Organic scintillators hold great promise for x‐ray imaging due to their solution processability and low cost, yet their practical application is fundamentally limited by weak x‐ray absorption and inefficient exciton utilization. Here, we overcome these limitations through a functional‐separation design that yields exceptional radioluminescence in a purely organic system. We have developed ionic phosphonium scintillators integrating thermally activated delayed fluorescence (TADF) cations with heavy‐atom‐containing organic anions. In this architecture, the organic anions act as sensitizing antennas for x‐ray photons, while the TADF cations independently govern the emission process. Upon x‐ray excitation, energy is unidirectionally transferred from the heavy anions to the luminophores, followed by efficient triplet harvesting via TADF—delivering materials that achieve photoluminescence quantum yields of up to 81%. Leveraging this molecular design, a highly doped (60 wt%) transparent screen based on the brominated compound achieves a remarkable spatial resolution of 97.8 lp/mm. The imaging screen enables clear visualization of fine structures, such as the internal wiring in electronic chips and a 400‐mesh copper grid. By decoupling x‐ray absorption from emission, our work establishes a new paradigm for designing solution‐processable organic scintillators with high radioluminescence performance, offering a promising pathway toward advanced x‐ray imaging applications.

Organic scintillators hold great promise for x‐ray imaging due to their solution processability and low cost, yet their practical application is fundamentally limited by weak x‐ray absorption and inefficient exciton utilization. Here, we overcome these limitations through a functional‐separation design that yields exceptional radioluminescence in a purely organic system. We have developed ionic phosphonium scintillators integrating thermally activated delayed fluorescence (TADF) cations with heavy‐atom‐containing organic anions. In this architecture, the organic anions act as sensitizing antennas for x‐ray photons, while the TADF cations independently govern the emission process. Upon x‐ray excitation, energy is unidirectionally transferred from the heavy anions to the luminophores, followed by efficient triplet harvesting via TADF—delivering materials that achieve photoluminescence quantum yields of up to 81%. Leveraging this molecular design, a highly doped (60 wt%) transparent screen based on the brominated compound achieves a remarkable spatial resolution of 97.8 lp/mm. The imaging screen enables clear visualization of fine structures, such as the internal wiring in electronic chips and a 400‐mesh copper grid. By decoupling x‐ray absorption from emission, our work establishes a new paradigm for designing solution‐processable organic scintillators with high radioluminescence performance, offering a promising pathway toward advanced x‐ray imaging applications.

Organic complex‐based materials show promise for replacing inorganic scintillators due to their low cost, mild synthesis and ease of processing into large‐area films. Specifically, ionic Ag(I) complexes offer both heavy‐atom‐enhanced x‐ray absorption and good solubility, enabling highly doped, transparent films ideal for high‐resolution x‐ray imaging. Yet, their development has been limited because silver's high oxidation potential impedes triplet exciton harvesting—a critical yet challenging process during x‐ray conversion where secondary electrons generate abundant triplet states. Here, we present a design strategy for metal‐to‐ligand charge‐transfer Ag(I) complexes exhibiting thermally activated delayed fluorescence (TADF) and report a series of ionic Ag(I)‐based scintillators. These materials achieve high reverse intersystem crossing rates (>10 ⁷ s ⁻¹ ) and microsecond‐scale decay lifetimes, enabling efficient triplet exciton harvesting during radioluminescence and light yields up to 53797 photons/MeV. Transparent films fabricated from these complexes demonstrate excellent x‐ray imaging performance with a spatial resolution of 86.7 lp/mm. This work offers new design principles for coordination‐compound scintillators and advances high‐performance scintillation technology.

Narrowband pure‐red emitters are essential for ultrahigh‐definition organic light‐emitting diode (OLED) displays. However, organic emitters with a full width at half maximum (FWHM) < 0.1 eV and CIE‐x > 0.67 (NTSC red standard) remain rare, as redshifted emission often causes spectral broadening and increased nonradiative decay. Herein, leveraging a facile chlorine‐oriented direct double borylation strategy that offers high synthetic accessibility and structural expandability, two pure‐red fluorophores with near‐unity photoluminescence quantum yields and unprecedentedly narrow emission are constructed through nearly coplanar decoration of peripheral triazine electron‐acceptors on a para‐boron‐substituted naphthalene multiresonance core. By simultaneously stabilizing the emissive state and suppressing high‐frequency vibrations, these emitters achieve extremely narrow emission (FWHM = 0.078 eV) and CIE coordinates of (0.69, 0.31) and (0.70, 0.30) in toluene. The phosphor‐assisted OLED achieves ultranarrow red emission centered at 629 nm (FWHM = 0.1 eV, CIE‐x = 0.69), approaching BT.2020 standard, with an external quantum efficiency of 26.6% and a power efficiency of 33.8 lm/W—among the best reported for pure‐red OLEDs. This work presents an efficient design strategy for red emitters that simultaneously achieves high color purity, ultra‐narrowband emission, high efficiency, and synthetic simplicity.

Scintillators have attracted considerable attention owing to their important applications in industrial inspection and medical X‐ray imaging. However, efficient harvesting of triplet excitons to achieve high radioluminescence (RL) efficiency remains highly challenging. Herein, we propose a metal‐coordination‐triggered strategy that activates anti‐Kasha phosphorescence, enabling triplet‐exciton‐dominated multiple radiative decay pathways that originate from both the lowest and second triplet states and the lowest singlet state. Coordination with Ag ⁺ effectively narrows the singlet–triplet energy gap and enhances spin–orbit coupling (SOC), thereby accelerating intersystem crossing (ISC) and facilitating radiative decay from higher‐lying triplet states. The resulting silver(I) complex exhibits pronounced anti‐Kasha phosphorescence and achieves a high photoluminescence quantum yield of up to 77.7% in PVP films. Multiple triplet radiative decay pathways and enhanced x‐ray absorption improve exciton harvesting efficiency, resulting in intensified radioluminescence. Together with the superior film quality of the silver(I) complex, this enables high‐resolution x‐ray imaging with a spatial resolution of 68.2 lp mm ^{− 1} , far exceeding that of the ligand (16.6 lp mm ^{− 1} ). These results demonstrate the critical role of metal‐fragment coordination in regulating excited‐state dynamics under x‐ray excitation and provide a new strategy for developing high‐performance anti‐Kasha phosphorescent scintillators with efficient triplet‐exciton utilization.