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Conventional room temperature phosphorescence (RTP) polymer materials lack a dynamic structural change mechanism for on-demand phosphorescence emission, limiting their application in specific scenarios, such as smart devices. However, the development of RTP polymer materials with an on-demand emission capability is highly attractive yet rather challenging. Herein, we report a novel RTP polymer material that doped purely organic chromophores into a polymer network with numerous free hydroxyl side chains. This unique polymer material can be 3D printed with RTP activated through thermal-triggered nonequilibrium transesterification, where on-demand phosphorescence emission is achieved because of the increased cross-linking degrees such that the thermal motion of chromophores is effectively restricted. As a result, ultralong RTP emission is successfully observed due to enhanced stiffness in the polymer network. Importantly, the modulus changes of the polymer during nonequilibrium transesterification are intuitively visualized based on the intensity of phosphorescence emission. Through liquid crystal display (LCD) 3D printing, complex shaped and multimaterial structured objects are demonstrated, targeting the information encryption of printed objects and on-demand regional emission of multicolored phosphorescence. This study would provide an avenue to control RTP with on-demand emission and contributes to the field of anticounterfeiting and detection applications for intelligent RTP materials.

Abstract The increase in anthropogenic carbon dioxide (CO2) emissions has exacerbated the deterioration of the global environment, which should be controlled to achieve carbon neutrality. Central to the core goal of achieving carbon neutrality is the utilization of CO2 under economic and sustainable conditions. Recently, the strong need for carbon neutrality has led to a proliferation of studies on the direct conversion of CO2 into carboxylic acids, which can effectively alleviate CO2 emissions and create high‐value chemicals. The purpose of this review is to present the application prospects of carboxylic acids and the basic principles of CO2 conversion into carboxylic acids through photo‐, electric‐, and thermal catalysis. Special attention is focused on the regulation strategy of the activity of abundant catalysts at the molecular level, inspiring the preparation of high‐performance catalysts. In addition, theoretical calculations, advanced technologies, and numerous typical examples are introduced to elaborate on the corresponding process and influencing factors of catalytic activity. Finally, challenges and prospects are provided for the future development of this field. It is hoped that this review will contribute to a deeper understanding of the conversion of CO2 into carboxylic acids and inspire more innovative breakthroughs.

Abstract Atomic‐level structural editing is a promising way for facile synthesis and accurately constructing dielectric/magnetic synergistic attenuated hetero‐units in electromagnetic wave absorbers (EWAs), but it is hard to realize. Herein, utilizing the rapid explosive volume expansion of the CoFe‐bimetallic energetic metallic triazole framework (CoFe@E‐MTF) during the heat treatment, the effective absorption bandwidth and the maximum absorption intensity of a series of atomic CoFe‐inserted hierarchical porous carbon (CoFe@HPC) EWAs can be modified under the diverse synthetic temperature. Under the filler loading of 15 wt%, the fully covered X and Ku bands at 3 and 2.5 mm for CoFe@HPC800 and the superb minimum reflection loss (RLmin) of −53.15 dB and specific reflection loss (SRL) of −101.24 dB mg−1 mm−1 for CoFe@HPC1000 are achieved. More importantly, the single‐atomic chemical bonding among Co─Fe on the nanopores is captured by extended X‐ray absorption fine structure, which reveals the formation mechanism of nanopore‐confined vortical dipoles and magnetic domains. This work heralds the infinite possibilities of atomic editing EWA in the future.

Despite increasing interest in organic room temperature phosphorescence, it can still be challenging to determine mechanism and develop practical applications. Here, the authors report room temperature phosphorescent systems from chiral components, with strong phosphorescence observed only when both host and guest had the same chirality.

Abstract Precise construction of isolated reactive centers on semiconductors with well‐controlled configurations affords a great opportunity to investigate the reaction mechanisms in the photocatalytic process and realize the targeted conversion of solar energy to steer the charge kinetics for hydrogen evolution. In the current research, we decorated isolated Ni atoms on the surface of CdS nanowires for efficient photocatalytic hydrogen production. X‐ray absorption fine structure investigations clearly demonstrate the atomical dispersion of Ni sites on the surface of CdS nanowires. Experimental investigations reveal that the isolated Ni atoms not only perform well as the real reactive centers but also greatly accelerate the electron transfer via direct Ni–S coordination. Theoretical simulation further documents that the hydrogen adsorption process has also been enhanced over the semi‐coordinated Ni centers through electronic coupling at the atomic scale.

Abstract Improving the atom utilization of metals and clarifying the M–M’ interaction is both greatly significant in assembling high-performance ultra-light electromagnetic wave-absorbing materials. Herein, a high-temperature explosion strategy has been successfully applied to assemble the hierarchical porous carbon sponge with Co–Fe decoration via the pyrolysis of the energetic metal organic framework. The as-constructed hybrid displays a superior reflection loss (RL) value of − 57.7 dB and a specific RL value of − 192 dB mg−1 mm−1 at 12.08 GHz with a layer thickness of 2.0 mm (loading of 15 wt%). The off-axis electron hologram characterizes the highly distributed numerous polarized nanodomain variable capacitors, demonstrating the dipole and interfacial polarization along the edges of the nanopores. More importantly, the X-ray absorption spectroscopy analysis verifies the mutual interaction between the metal cluster and carbon matrix and the electronic coupling responsible for the greatly improved electromagnetic wave absorption.

Abstract Many aggregation‐induced emission (AIE) systems exhibit broad and structureless luminescence emission spectra resembling the Gaussian distribution, which is likely due to kinetically locked molecular conformers in the condensed phase. To verify the hypothesis, a series of tetraphenylethene (TPE) derivatives are synthesized and characterized as aqueous nanoparticle suspensions. It is found that the unsubstituted TPE exhibits reduced fluorescence intensity accompanied by a blueshift of the emission maximum, after the temperature of the aqueous suspension is elevated and cooled to room temperature again. For a naphthalimide‐substituted TPE compound, thermal treatment of the AIE aqueous suspension results in complete, irreversible aggregation‐caused quenching (ACQ) of fluorescence, which can be restored by a redissolving‐precipitation process of thermally treated aggregates. The phenomenon is ascribed as a relative population shift of a kinetic AIE (k‐AIE) state to a thermodynamic AIE (t‐AIE) or ACQ state, evidenced by differential scanning calorimetry, dynamic light scattering, and scanning electron microscopy. The phenomenon may be universal for many other AIE systems and could be explored as stimuli‐responsive materials.