Two redox-active porous organic frameworks (POFs) with a built-in radical moiety (TEMPO) and hierarchical porous structures were synthesized through a facile bottom-up strategy and studied as cathode materials for lithium-sulfur (Li-S) batteries. The sulfur loading in these two POFs reached 61 %, benefitting from their large pore volumes. Owing to the highly dense docking sites of TEMPO, sulfur could be covalently immobilized within the porous networks and efficiently inhibit the shuttle effect, thereby significantly improving the cycling performance. The composites TPE-TEMPO-POF-S (TPE=tetraphenylethene) deliver a capacity in excess of 470 mAh g after 200 cycles with a coulombic efficiency of around 100 % at a current rate of 0.1 C. Furthermore, TEMPO-POFs with sulfur embedded showed excellent rate capability with limited capacity loss at rates of 0.1-1 C.

Two nitrogen-rich porous organic polymers (POPs) were prepared via Schiff base chemistry. Carbonization of these POPs results in porous carbon nanohybrids which exhibit excellent catalytic activity toward the oxygen reduction reaction (ORR).

Red phosphorus (P) has been considered to be one of the most promising anode materials for sodium-ion batteries (SIBs) because of its highest theoretical capacity (∼2600 mA h g). For the first time, we report a reliable hydrothermal method for the preparation of red phosphorus quantum dots (RPQDs) with commercial red P as a source. Moreover, an effective strategy was designed to fabricate RPQDs/rGO nanohybrids for addressing the intrinsic issues of red P as anode materials for SIBs. Benefiting from the nanostructuring of red P and the coupling of RPQDs with rGO, the obtained nanohybrids not only promote electron and ion transfer, but also effectively enhance the electronic conductivity, restrain the aggregation of RPQDs and buffer the large volume changes of red phosphorus during the charge-discharge process. The nanohybrids deliver an initial specific capacity of 1161 mA h g and a low capacity deterioration rate of less than 0.12% per cycle even after 250 cycles at a current density of 200 mA g. The feasibility of large-scale production of the RPQDs/rGO nanohybrid, associated with its outstanding Na-ion storage properties and low cost, demonstrates that the RPQDs/rGO hybrid is a very promising anode material for SIBs.

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Temporal persistence is as important for nanocarriers as spatial accuracy. However, because of the insufficient aggreagtion and short retention time of chemotherapy drugs in tumors, their clinical application is greatly limited. A drug delivery approach dependent on the sensitivity to an enzyme present in the microenvironment of the tumor is designed to exhibit different sizes in different sites, achieving enhanced drug permeability and retention to improve tumor nanotherapy efficacy. In this work, we report a small-molecule peptide drug delivery system containing both tumor-targeting groups and enzyme response sites. This system enables the targeted delivery of peptide nanocarriers to tumor cells and a unique response to alkaline phosphatase (ALP) in the tumor microenvironment to activate morphological transformation and drug release. The amphiphilic peptide AYR self-aggregated into a spherical nanoparticle structure after encapsulating the lipid-soluble model drug doxorubicin (DOX) and rapidly converted to nanofibers via the induction of ALP. This morphological transformation toward a high aspect ratio allowed rapid, as well as effective drug release to tumor location while enhancing specific toxicity to tumor cells. Interestingly, this "transformer"-like drug delivery strategy can enhance local drug accumulation and effectively inhibit drug efflux. In vitro along with in vivo experiments further proved that the permeability and retention of antitumor drugs in tumor cells and tissues were significantly enhanced to reduce toxic side effects, and the therapeutic effect was remarkably improved compared with that of nondeformable drug-loaded peptide nanocarriers. The developed AYR nanoparticles with the ability to undergo morphological transformation in situ can improve local drug aggregation and retention time at the tumor site. Our findings provide a new and simple method for nanocarrier morphology transformation in novel cancer treatments.

Interpenetrating porous organic polymers (PNFc‐POP) inspired by the structure of DNA were synthesized through a two‐stage polymerization method under catalyst‐free conditions. A ferrocene‐rich hyper‐crosslinked polymer (Fc‐melamine) was interwoven with cyclotriphosphazene‐based conjugated porous polymer (PN‐CMP) to obtain an interconnected polymer network (PNFc‐POP). The sequential interpenetrating polymer network contained a diverse range of heteroatoms (P, N, O and Fe) and exhibited a large BET surface area. Simple pyrolysis of the dual polymer interweaved skeletons at 900 °C afforded nanocrystalline FeP/Fe2P‐embedded N and P codoped porous carbon composites. The optimal catalyst obtained by the pyrolysis of PNFc‐POP at 900 °C (PNFc‐900) exhibited hierarchical porosity and large BET surface areas. It also exhibited excellent oxygen reduction reaction catalytic activities over the entire pH range. The onset potential (Eonset=1.01 V) and half‐wave potential (E1/2=0.86 V) of PNFc‐900 exceeded those of commercial Pt/C (Eonset=0.99 V and E1/2=0.84 V) in alkaline conditions. The obtained catalysts with a four‐electron transfer pathway for the reduction of oxygen also displayed excellent long‐term stability and methanol tolerance.

Patients with cancer have reduced immune function and are susceptible to bacterial infection after surgery, chemotherapy, or radiotherapy. Spherical nanoparticles formed by the self-assembled peptide V 6 K 3 can be used as carriers for poorly soluble antitumor drugs to effectively deliver drugs into tumor cells. V 6 K 3 was designed to achieve nanoparticle-to-nanofiber geometric transformation under induction by plasma amine oxidase (PAO). PAO is commercially available and functionally similar to lysyl oxidase (LO), which is widely present in serum. After the addition of fetal bovine serum (FBS) or PAO, the secondary structure of the peptide changed, while the spherical nanoparticles stretched and transformed into nanofibers. The conversion of the self-assembled morphology reveals the susceptibility of this amphiphilic peptide to subtle chemical modifications and may lead to promising strategies to control self-assembled architecture via enzyme induction. Enzymatically self-assembled V 6 K 3 had bactericidal properties after PAO addition that were surprisingly superior to those before PAO addition, enabling this peptide to be used to prevent infection. The amphiphilic peptide V 6 K 3 displayed antitumor properties and low toxicity in mammalian cells, demonstrating good biocompatibility, as well as bactericidal properties, to prevent bacterial contamination. These advantages indicate that enzymatically self-assembled V 6 K 3 has great biomedical application potential in cancer therapy.

Here, a novel joint chemo/photothermal/chemodynamic therapy was developed using a pH/GSH/photo triple-responsive 2D-covalent organic framework (COFs) drug carriers for passive target treatment of tumor with extraordinarily high efficiency. The well-designed...