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In the deep‐ultraviolet (DUV) region, nonlinear optical (NLO) crystals must meet stringent requirements, including a large optical band gap and sufficient second harmonic generation (SHG) response. Typically, these criteria are fulfilled by borates, carbonates and nitrates containing π‐conjugated groups. In contrast, sulfates and phosphates, with polarizabilities significantly smaller than those of π‐conjugated groups, struggle to achieve similar performance. Here, we present the discovery of Mg2PO4Cl, a magnesium‐based phosphate, identified from over 10,000 phosphates based on a polar‐axial‐symmetry screening strategy, which exhibits the highest SHG response (5.2×KH2PO4 (KDP)) with phase‐matching ability among non‐π‐conjugated DUV transparent NLO crystals. This compound belongs to the Pna21 space group, with [PO4] units consistently aligned along the 21 screw axis and glide planes throughout its crystal structure. Theoretical calculations attribute its remarkable SHG effect to the orderly arrangement of heteroanionic [MgO5Cl] and [MgO4Cl2] polyhedra alongside isolated [PO4] tetrahedra, supported by Berry phase analysis. Furthermore, a crystallographic structure analysis of phosphates and sulfates with significant SHG effects validates the effectiveness of our screening strategy. These findings offer valuable insights into the origins of NLO effects in non‐π‐conjugated compounds from both a material design and structural chemistry perspective, inspiring future efforts to revitalize DUV phosphates. [ABSTRACT FROM AUTHOR]

Energy‐saving and value‐added management in advanced catalysis is highly desirable but is challenged by the limitations of multifunctional catalysts and catalytic modules. Herein, an azo‐linked phthalocyanine‐porphyrin covalent organic framework (COF) with the ultrathin layered nanostructure grown on carbon nanotubes (NiPc‐azo‐H2Pp@CNTs) has been designed and synthesized, which can serve as a highly active and stable bifunctional heterojunction electrocatalyst for selective paired‐electrosynthesis through coupling anodic iodide oxidation reaction and cathodic CO2 conversion. Particularly, the inbuilt local microenvironment conferred by the dihydroporphyrin moieties in COF can act as a proton reservoir to promote the proton relay at the heterojunction interface during the electrocatalytic process. Moreover, through the cascade construction of dual electrocatalytic/organocatalytic modules, the cathode‐generated CO can be further converted to dimethyl carbonate with a yield of 6.21 mmol L−1 h−1, while the anode‐produced iodine can be derived into iodoform on the hundred‐milligram scale. It is worth noting that the value‐added cascade synthesis mediated by paired‐electrolysis using the distinctive and high‐powered electrocatalysts will help advance the sustainable development of industrial intelligent manufacturing. [ABSTRACT FROM AUTHOR]

Circularly polarized luminescence (CPL) active materials have attracted widespread attention because of their potential applications. Nonetheless, it is still a great challenge to fabricate CPL materials with both high fluorescence quantum efficiency (Φ) and high luminescent asymmetry factor (glum). According to the unique structure characteristics of chiral layered metal–organic frameworks (CLMOFs), herein a novel strategy to construct high‐performance CPL materials, by utilizing the confinement effect of CLMOFs is developed. Conjugate dye molecules, such as fluorescent brighteners, fluorescein, and rhodamine B, which are readily subjected to aggregation‐caused quenching (ACQ) effect, are successfully intercalated into CLMOF matrix, affording blue, yellow–green, and red CPL, respectively. Both high Φ and glum values of up to 91% and 0.069 are obtained, owing to the distinct confinement effect of CLMOFs. After confining dye molecules within CLMOF, the ACQ effect is effectively inhibited, which is beneficial for fluorescence enhancement; simultaneously, the chirality transfer from CLMOF matrix to dyes by controlling their arrangement in the chiral confinement microenvironment, leading to the high glum values. Based on the full‐color and strong CPL, a multi‐dimensional code system is proposed. This work paves a new avenue to design and assemble CPL materials with high Φ and glum, which can be widely adopted. [ABSTRACT FROM AUTHOR]

The covalent organic frameworks/polymers configurated with metal‐N4 conjugated structures offer an exceptional platform for efficient electrochemical CO2 reduction reaction (eCO2RR). However, understanding the impact of the structure‐mediated local microenvironment and integrating CO2 electroreduction with follow‐up utilization toward extending chemical valorization of CO2 are still far from sufficient. Herein, a set of covalent phenanthroline‐porphyrin polymers are designed to decode the microenvironment modulation originating from built‐in structures, and the optimized one delivered an extraordinary performance for eCO2RR with ≈100% Faradaic efficiency of CO under stabilized CO2‐electrolysis of 70 h. The experimental and theoretical analyses suggest that the regulation of the Co‐N4 electronic structures and microenvironment convoys the stabilized formation of key reaction intermediate *COOH. Furthermore, through CO‐mediated electro/thermocatalytic tandem processes, the aminocarbonylation of aryl iodides and amines with high yields has been convincingly implemented over the coordinated Pd sites, which is remarkably helpful to propel extending chemical valorization of CO2. [ABSTRACT FROM AUTHOR]

The coupling electrosynthesis involving CO2 upgrade conversion is of great significance for the sustainable development of the environment and energy but is challenging. Herein, we exquisitely constructed the self‐supported bimetallic array superstructures from the Cu(OH)2 array architecture precursor, which can enable high‐performance coupling electrosynthesis of formate and adipate at the anode and the cathode, respectively. Concretely, the faradaic efficiencies (FEs) of CO2‐to‐formate and cyclohexanone‐to‐adipate conversion simultaneously exceed 90% at both electrodes with excellent stabilities. Such high‐performance coupling electrosynthesis is highly correlated with the porous nanosheet array superstructure of CuBi alloy as the cathode and the nanosheet‐on‐nanowire array superstructure of CuNi hydroxide as the anode. Moreover, compared to the conventional electrolysis process, the cell voltage is substantially reduced while maintaining the electrocatalytic performance for coupling electrosynthesis in the two‐electrode electrolyzer with the maximal FEformate and FEadipate up to 94.2% and 93.1%, respectively. The experimental results further demonstrate that the bimetal composition modulates the local electronic structures, promoting the reactions toward the target products. Prospectively, our work proposes an instructive strategy for constructing adaptive self‐supported superstructures to achieve efficient coupling electrosynthesis. [ABSTRACT FROM AUTHOR]