No abstract

Metal–organic frameworks (MOFs), which consist of central metal nodes and organic linkers, constitute a fast growing class of crystalline porous materials with excellent application potential. Herein, a series of Mn‐based multimetallic MOF (bimetallic and trimetallic MIL‐100) nano‐octahedra are prepared by a facile one‐pot synthetic strategy. The types and proportions of the incorporated elements can be tuned while retaining the original topological structure. The introduction of other metal ions is verified at the atomic level by combining X‐ray absorption fine structure experiments and theoretical calculations. Furthermore, these multimetallic Mn‐based MIL‐100 nano‐octahedra are utilized as sulfur hosts to prepare cathodes for Li–S batteries. The MnNi‐MIL‐100@S cathode exhibits the best Li–S battery performance among all reported MIL‐100@S composite cathode materials, with a reversible capacity of ≈708.8 mAh g−1 after 200 cycles. The synthetic strategy described herein is utilized to incorporate metal ions into the MOF architecture, of which the parent monometallic MOF nano‐octahedra cannot be prepared directly, thus rationally generating novel multimetallic MOFs. Importantly, the strategy also allows for the general synthesis and study of various micro‐/nanoscale MOFs in the energy storage field.

The therapeutic outcome of photothermal therapy (PTT) remains impeded by the transparent depth of light. Combining PTT with immunotherapy provides strategies to solve this problem. Regulating metabolism‐related enzymes is a promising strategy to stimulate immune response. Here, a nanosystem (NLG919/IR780 micelles) with the properties of photothermal conversion and regulation of the tryptophan metabolic pathway is used to suppress the growth of the tumor margin beyond effective PTT and promote tumor PTT and immunotherapy. It is revealed that mild heat treatment promotes the growth of the tumor margin beyond effective PTT for the upregulation of heat shock protein (HSP), indoleamine 2,3‐dioxygenase (IDO), and programmed death‐ligand 1 (PD‐L1). The NLG919/IR780 micelles can effectively inhibit the activity of IDO but do not affect the level of IDO expression. NLG919/IR780 micelles can effectively accumulate in the tumor and can migrate to lymph nodes and the lymphatic system. In vivo antitumor studies reveal that NLG919/IR780 micelles effectively suppress the growth of tumor margin following PTT in primary tumors. NLG919/IR780 micelle‐mediated PTT and IDO inhibition further stimulate the activation of T lymphocytes, inhibiting the growth of distal tumors (abscopal effect). The results demonstrate that the NLG919/IR780 micelles combine PTT and immunotherapy and suppress the tumor margin as well as distal tumor growth post photothermal therapy.

In this study, we propose a versatile method for synthesizing uniform three-dimensional (3D) metal carbides, nitrides, and carbonitrides (MXenes)/metal-organic frameworks (MOFs) composites (Ti 3 C 2 T X /Cu-BTC, Ti 3 C 2 T X / Fe,Co-PBA, Ti 3 C 2 T X /ZIF-8, and Ti 3 C 2 T X /ZIF-67) that combine the advantages of MOFs and MXenes to enhance stability and improve conductivity. Subsequently, 3D hollow Ti 3 C 2 T X /ZIF-67/CoV 2 O 6 composites with excellent electronand ion-transport properties derived from Ti 3 C 2 T X /ZIF-67 were synthesized. The specific capacitance of the Ti 3 C 2 T X / ZIF-67/CoV 2 O 6 electrode was 285.5 F g À 1 , which is much higher than that of the ZIF-67 and Ti 3 C 2 T X /ZIF-67 electrode. This study opens a new avenue for the design and synthesis of MXene/MOF composites and complex hollow structures with tailorable structures and compositions for various applications.