Polyimides (PIs) are widely used in the microelectronics field due to their excellent comprehensive performance and the diversity and designability of their structures. In flexible substrate applications, designing the molecular structure to balance thermodynamic and optical properties is the most critical part of the PI design process. To accelerate the discovery of high-performance PIs, we established predictive models for glass transition temperature (T_g), cut-off wavelength (CW), and coefficient of thermal expansion (CTE) using various machine learning algorithms. The optimal predictive models for the three properties demonstrated high accuracy and stability in both test set predictions and cross-validation results. Additionally, the interpretability of the three optimal models was analyzed using the SHAP method, and the accuracy and generalization ability of the models were validated using several novel PIs. By combining the three models, predictions were made for multiple PIs, leading to the selection and synthesis of PIs with excellent comprehensive performance. 135 novel PIs were designed and their key properties were obtained without the need for experimental verification. The predictive models established in this study can assist researchers in quickly determining the T_g, CW and CTE of PIs, thereby facilitating the swift identification of promising candidates for further development.

Emerging therapies rely on the efficient and specific delivery of targeted agents into the cytosol, such as DNA, siRNA and proteins. Nanoparticles showed great potentials in safe delivery and transportation of the targeted cargoes; however, the entrapment in endosomes and degradation by specific enzymes in the lysosome hindered the bioavailability, cytosolic delivery and subsequent therapeutic efficacy. In this case, the development of methods for efficient and specific delivery of targeted therapeutic agents focuses on overcoming the major challenge of endo/lysosomal escape, which relies on the development of safe and efficient nano-delivery systems. A deeper mechanistic understanding in the endo/lysosomal escape will guide the development of more efficient nano-delivery systems. In this review, we summarize various mechanisms by which nanoparticles escape from the endo/lysosome, and showcase the recent progress in dissecting the endo/lysosomal approaches based on nano-delivery systems. Emphasis will lie on the properties of nanoparticles that govern the endo/lysosomal escape pathway as well as the latest promising applications in vaccine delivery and genetic engineering field.

Acute kidney injury (AKI) represents a substantial challenge to public health and is characterized by elevated occurrence and fatality rates. In the last 3 decades, the disruption of iron homeostasis and the cytotoxic effects mediated by iron have been extensively acknowledged as contributors to, as well as outcomes of, renal damage. Therefore, iron metabolism has become the focus of novel therapeutic interventions for AKI, with targeted iron metabolism strategies showing great potential. In this review, we have explored the dysregulation of iron metabolism in AKI and the AKI caused by iron metabolism disorders. We have summarized the complex mechanisms of iron metabolism in the kidney and emphasized the potential role of iron metabolism-related metabolic pathways in the treatment and prevention of AKI. Finally, we have reviewed various strategies targeting iron metabolism for the treatment of AKI, hoping to provide more effective treatment options for AKI patients in the future.

In photolithography, shortening the exposure wavelength from ultraviolet to extreme ultraviolet (EUV, 13.5 nm) and soft X-ray region in terms of beyond EUV (BEUV, 6.X nm) and water window X-ray (WWX, 2.2-4.4 nm) is expected to further miniaturize the technology node down to sub-5 nm level. However, the absorption ability of molecules in these ranges, especially WWX region, is unknown, which should be very important for the utilization of energy. Herein, the molar absorption cross sections of different elements at 2.4 nm of WWX were firstly calculated and compared with the wavelengths of 13.5 nm and 6.7 nm. Based on the absorption cross sections in these ranges and density estimation results from the density-functional theory calculation, the linear absorption coefficients of typical resist materials, including metal-oxy clusters, organic small molecules, polymers, and photoacid generators (PAGs), are evaluated. The analysis suggests that the Zn cluster has higher absorption in BEUV, whereas the Sn cluster has higher absorption in WWX. Doping PAGs with high EUV absorption atoms improves chemically amplified photoresist (CAR) polymer absorption performance. However, for WWX, it is necessary to introduce an absorption layer containing high WWX absorption elements such as Zr, Sn, and Hf to increase the WWX absorption.

Dimethyl carbonate (DMC) is an important chemical raw material extensively used in organic synthesis, lithium-ion battery electrolytes, etc. The primary method for industrial synthesis of DMC involves transesterification between ethylene carbonate and MeOH but faces issues with difficult catalyst separation and low catalytic activity. Based on the synergistic catalytic activity of cation and anion, this study develops poly(ionic liquid)s of [N_XPIL][PHO] and [N₃PIL][Y] with varying alkaline sites and alkalinity levels. This is accomplished by constructing functional polymer monomers containing free radical polymerization sites and nitrogen-containing alkaline groups, and by polymerizing them with suitable cross-linking monomers in a specific ratio before exchanging the resulting polymers with different anions. Results show that doping with nitrogen-containing alkaline groups leads to enhanced basic functional sites while appropriate anions provide intensified alkalinity levels. The [N₃PIL][PHO] obtained exhibits superior catalytic activity in transesterification synthesis of DMC, with a yield of 91.43% and selectivity of 99.96% at a reaction time of 2 h. The study also investigates the impact of poly(ionic liquid) cationic structure and anion types, as well as their interactions, on catalytic performance. The findings reveal that the catalytic activity of poly(ionic liquid) is restricted by the interactions between cation and anion. Based on these findings, a possible reaction mechanism was proposed, providing theoretical support for the high-efficiency production of DMC.

Luminescent nanoclusters (NCs) have attracted much attention because of their superior photophysical properties; however, the design of dynamic NCs with reversible structural change is highly challenging. Herein, we synthesize a kind of dynamic luminescent NCs through Schiff base crosslinking between triethylenetetramine (TETA) and tannic acid at room temperature. The proposed NCs have an excitation-independent blue emission, and the maximum emission is available at about 458 nm with two excitation centers. Furthermore, the crosslinking degree of the NCs can be effectively adjusted by TETA and their formation is a kinetic-control process. Most importantly, the proposed NCs show a property of pH-controlled reversible depolymerization and polymerization, accompanied by a cyclic “on-off-on” photoswitching, which is directly attributed to pH-stimulated reversible C=N bond cleavage and re-formation. Because of the reversible structure change properties, the dynamic NCs have been well used in reversible information encryption. This new finding provides not only us with a powerful strategy to study the structure-properties relationship of luminescent NCs but also a design idea for constructing smart optical nanomaterials.

Stimulus-responsive organic room temperature phosphorescent (RTP) materials have received significant attention in bioimaging, sensing, and data storage because of their controllable dynamic variability and rapid response. Organic co-crystals, with tailor-designed optical properties through manipulation of their aggregate structures, have proven to be very effective in elucidating the structure-property relationship of organic RTP materials at the molecular level. Therefore, enhancing RTP through rigid frameworks that promote intersystem crossing is a valid approach. Notably, the realization of organic RTP co-crystal performance by altering the components or adjusting the crystal lattices is highly appealing; however, this has not been fully addressed. In this study, an organic RTP co-crystal, 4,4′-bipyridine (44BD), was employed as the host, and 1,4-diiodotetrafluorobenzene (DITF) and 4-bromo-2,3,5,6-tetrafluorobenzoic acid (TFBA) were employed as guests. The 44BD-DITF co-crystal exhibited an orange RTP, whereas 44BD-TFBA displayed a bright yellow RTP. Crystal analysis and theoretical calculations revealed that dense molecular packing and abundant intermolecular interactions within these co-crystals are crucial for the emergence of RTP. Notably, both co-crystals show a reversible acid/base stimulus response, that is, exposure to hydrochloric acid (HCl) fumes results in quenching of their RTP, which can be subsequently restored by triethylamine (TEA) fumigation. This study presents an effective approach towards reversible RTP switching in organic co-crystals, thus offering opportunities for the development of acid/base stimulus-responsive materials for next-generation applications.

Most of acridine based thermally activated delayed fluorescence (TADF) emitters are characterized by advantageous reverse intersystem crossing (RISC) rate (k_RISCs) due to the perpendicular orientation of the acridine donor to the acceptor moiety, but suffer from a poor radiation rate (k_r) typically in the order of 10⁶ s⁻¹. Herein, two sky blue TADF emitters 3,6-DMAC-AD-Py and 3,6-SFAC-AD-Py were developed by linking acridine (DMAC) and spiro-fluorene-acridine (SFAC) donors to 10-(pyridin-2-yl)acridin-9(10H)-one (AD-Py) acceptor. Larger SFAC and electron-deficient pyridyl groups are deliberately incorporated in 3,6-SFAC-AD-Py since the unique through-space interaction between them is designed to drive the rotation of inner acridine ring in SFAC for enhancing frontier molecular orbitals overlap while keeping a decent TADF behavior. Thus, the k_r of 3,6-SFAC-AD-Py is increased to 1.5 × 10⁷ s⁻¹. Simultaneously, SFAC donors improve spin orbital coupling strength and reduce the energy gaps, generating k_RISC of 1.8 × 10⁶ s⁻¹. This is the first acridine donor based TADF emitter realizing k_r of 10⁷ s⁻¹ and k_RISC of 10⁶ s⁻¹ by a through-space interaction strategy. 3,6-SFAC-AD-Py enables a highly efficient sky-blue organic light-emitting diode with a maximum external quantum efficiency (EQE) of 34.7% and Commission International de I'Eclairage coordinates of (0.19, 0.37). More importantly, the EQE still remained 27.6% and 16.9% at high brightness of 1000 and 10,000 cd m⁻².

Aliphatic polyesters and polycarbonates are among the promising sustainable polymers, which exhibit unique degradability and chain-chain interactions owing to their heterofunctionality. However, monocomponent aliphatic polyesters and polycarbonates usually suffer from inferior properties and functionalities. By contrast, precisely modulated block copolymers composed of polyesters and polycarbonates give rise to sustainable materials with tailored performance. An efficient approach to synthesize the block copolymers is the ring-opening (co)polymerization of the heterocycle monomers. Herein, this review presents the heterocycle monomer ring-opening (co)polymerization for the formation of sequence-controlled block polyesters and polycarbonates. Available synthetic strategies, different monomers, monomer combinations and the catalyst systems for the formation of different block polyesters and polycarbonates are summarized.