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Photodynamic therapy (PDT) plays a crucial role in treating cancer and major infectious diseases. However, the hypoxic microenvironment and deep-seated tumors often compromise the effectiveness of photosensitizers (PSs). PSs primarily generate type-II reactive oxygen species (ROS), which are limited under hypoxic conditions. Pyridinium salts frequently exhibit critical dark toxicity in vitro. Moreover, PDT alone often fails to achieve optimal anti-tumor effects compared to its combined application with photothermal therapy (PTT). To address these issues, we replaced pyridinium with quinolinium, significantly reducing dark toxicity. Additionally, the incorporation of benzophenone enhanced ROS generation, achieving a synergistic effect of type-I and type-II PDT. Fine-tuning the conjugated structure enhanced the donor–acceptor (D–A) intensity, while the stretching vibrations of carbon–carbon double bonds and carbon–nitrogen triple bonds red-shifted the excitation wavelength to the near-infrared (NIR) region and improved the photothermal conversion efficiency (PCE). This strategy provides a molecular design approach for achieving synergy between PDT and PTT. The synthesized four NIR-emitting aggregation-induced emission quinolinium salts exhibited mitochondrial targeting ability and low dark toxicity. Among them, FCN-TPAQ-BP showed excellent ROS generation capability, a PCE of 39.2%, good biocompatibility, and low dark toxicity, making it an ideal candidate for enhancing PDT's antitumor efficacy. [ABSTRACT FROM AUTHOR]

Thio-benzothioxanthene imide (BTXI) exhibits long excited state lifetime (τT = 17.7 μs) and high ISC efficiency (ΦΔ = 97%). For the first time, BTXI derivatives were used as photosensitizers for triplet–triplet annihilation upconversion, achieving the highest efficiency of 13.8%. In addition, thio-BTXI derivatives were used as photoinitiators for photopolymerization, resulting in a series of green light-activated radical polymerization systems. [ABSTRACT FROM AUTHOR]

Bismuth (Bi) possesses an ultrahigh theoretical volume capacity (3800 mAh cm−3) and low embedding potential stimulated considerable attention as anodes for sodium‐ion batteries (SIBs). However, its practical application is still hampered by the huge volume variation during the charge/discharge process. To settle this issue, Bi@C nanosheet arrays (Bi@C‐NSA) are fabricated on copper foam via a facile galvanic replacement followed by in situ polymerization of dopamine and an annealing procedure. The carbon‐coated nanosheet array structure not only accommodates the volume expansion during cycling and maintains electrode stability, but also facilitates rapid electron/ion transport. Due to the unique structural design, this Bi@C‐NSA exhibits an impressive capacity of 315.72 mAh g−1 after 1500 cycles under 1 A g−1. Furthermore, a series of in situ/ex situ techniques reveal that this Bi@C‐NSA possesses superior reaction kinetics and undergoes a typical alloying/dealloying storage mechanism. Furthermore, Bi@C‐NSA also achieves commendable reversible capacity and cycling stability in a wide temperature range (0 °C–60 °C). Notably, the assembled Na3V2(PO4)3//Bi@C‐NSA full cell demonstrates a capacity of 325 mAh g−1 after 50 cycles at 0.05 A g−1, which promises for practical applications. This galvanic replacement strategy spearheads a way to prepare nanoarray electrodes and will accelerate the development of sodium‐ion batteries. [ABSTRACT FROM AUTHOR]

The unfavorable photochemical processes at the molecular level have become a barrier limiting the use of aromatic amides as high‐performance luminescent materials. Herein, we propose a reliable strategy for manipulating noncovalent conformational lock (NCL) via side‐chain engineering to burst out eye‐catching luminescence at the aggregate level. Contrary to the invisible emission in dilute solutions, dyad OO with a three‐centered H‐bond gave the wondrous crystallization‐induced emission with a quantum yield of 66.8% and clusterization‐triggered emission, which were much brighter than those of isomers. Theoretical calculations demonstrate that crystallization‐induced planarized intramolecular charge transfer (PICT), conformation rigidification, and through‐space conjugation (TSC) are responsible for aggregate‐state luminescence. Robust NCL composed of intramolecular N‐H···O interactions could boost molecular rigidity and planarity, thus greatly facilitating PICT and TSC. This study would inspire researchers to design efficient luminescent materials at the aggregate level via rational conformational control. [ABSTRACT FROM AUTHOR]

Hot exciton emitters have been confirmed as promising materials for the construction of blue organic light-emitting diodes (OLEDs). Here, two new deep-blue hot exciton emitters, D–A type BOOAn and A–D–A type 2BOOAn, are designed and synthesized by using the rigid oxygen-bridged triarylboron structure as the acceptor (A) and anthracene as the donor (D). The 2BOOAn-based doped devices achieved efficient deep-blue emission with a maximum external quantum efficiency (EQEmax) of 10.1%, an electroluminescence (EL) emission peak at 440 nm, CIE coordinates of (0.151, 0.073), and a calculated exciton utilisation efficiency (EUE) of 46–68%. Finally, the presence of reverse intersystem crossing from high-lying triplet T2 to S1 (hRISC) was experimentally verified. In addition, the transient EL (Tr-EL) analysis and the magneto-electroluminescence (MEL) measurement showed that the TTA mechanism hardly contributes to the EL process, so the high EUE of the device can be mainly attributed to the hot exciton mechanism. [ABSTRACT FROM AUTHOR]

Currently, most photoredox catalysis polymerization systems are limited by high excitation power, long polymerization time, or the requirement of electron donors due to the precise design of efficient photocatalysts still poses a great challenge. Herein, we propose a new approach: the creation of efficient photocatalysts having low ground state oxidation potentials and high excited state energy levels, along with through‐space charge transfer (TSCT) induced intersystem crossing (ISC) properties. A cabazole‐naphthalimide (NI) dyad (NI‐1) characterized by long triplet excited state lifetime (τT=62 μs), satisfactory ISC efficiency (ΦΔ=54.3 %) and powerful reduction capacity [Singlet: E1/2 (PC+1/*PC)=−1.93 eV, Triplet: E1/2 (PC+1/*PC)=−0.84 eV] was obtained. An efficient and rapid polymerization (83 % conversion of 1 mM monomer in 30 s) was observed under the conditions of without electron donor, low excitation power (10 mW cm−2) and low catalyst (NI‐1) loading (<50 μM). In contrast, the conversion rate was lower at 29 % when the reference catalyst (NI‐4) was used for photopolymerization under the same conditions, demonstrating the advantage of the TSCT photocatalyst. Finally, the TSCT material was used as a photocatalyst in practical lithography for the first time, achieving pattern resolutions of up to 10 μm. [ABSTRACT FROM AUTHOR]