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to perform PDT. [7] PSs absorb laser energy in the presence of O 2 to produce cytotoxic reactive oxygen species (ROS) such as singlet oxygen ( 1 O 2 ) that causes the destruction of the genetic material in cancer cells, leading to cell apoptosis, or necrosis. [7][8][9][10] The O 2 involved in PDT improves tumor destruction and reduces the toxic side effects as compared with other conventional therapeutic modalities like radiotherapy, chemotherapy, and surgery. [11][12][13][14][15] However, hypoxia, one of the hallmarks of malignant tumors, [16][17][18] induces an unexpected resistance of tumors to PDT, since molecular O 2 plays an essential role during the process. Some types of nanocatalysts have been used to address this dilemma, such as manganese dioxide (MnO 2 ) nanoparticles, carbon dot, and single-atom ruthenium (Ru) for an in situ catalysis of the decomposition of H 2 O 2 to generate O 2 . [6,14,19] This could be an effective strategy to relieve hypoxia in the tumor microenvironment (TME), thus becoming a potential approach to improve the efficacy of PDT. [20] Additionally, the acidic TME with an excessive amount of H 2 O 2 is a natural activator of these nanocatalysts, making them intelligent nanocatalysts for tumor specific therapy. [21][22][23] Recently, MnO 2 nanostructures have received extensive attention in the field of bio-applications for their efficient O 2 production and easy synthesis, [24][25][26][27] enhancing the effect of radiation therapy, [27] chemotherapy, [28] and PDT. [29] In addition, MnO 2 is rapidly decomposed into water soluble Mn 2+ ion in an acidic condition, [6,[30][31][32][33][34] and excreted through the bile into the feces, avoiding unexpected accumulation and long-term toxicity in vivo. [6,29] However, MnO 2 nanostructures without surface coating have a poor structure stability under physiological conditions, [35] and it is difficult to control their size and morphology during the synthesis, thus, increasing the uncertainty of the reactivity of the nanomaterial. [25] Therefore, it is highly desirable to construct MnO 2 nanoparticles with uniform morphology, high stability and biocompatibility for biomedical applications.Ferritin (Ftn) is an endogenous iron storage protein composed of 24 subunits, with a hollow structure of 12 nm in the external diameter and an inner cavity of 8 nm. [36] Ftn has been widely used as a superior protein nanocage for the Hypoxia is a hallmark of the tumor microenvironment (TME) that promotes tumor development and metastasis. Photodynamic therapy (PDT) is a promising strategy in the treatment of tumors, but it is limited by the lack of oxygen in TME. In this work, an O 2 self-supply PDT system is constructed by co-encapsulation of chlorin e6 (Ce6) and a MnO 2 core in an engineered ferritin (Ftn), generating a nanozyme promoted PDT nanoformula (Ce6/ Ftn@MnO 2 ) for tumor therapy. Ce6/Ftn@MnO 2 exhibits a uniform small size (15.5 nm) and high stability due to the inherent structure of Ftn. The fluorescence imaging and immunofluorescence analysis dem...

Complex spinel titanate Li 2 MTi 3 O 8 (M ¼ Co, Zn, Co 0.5 Zn 0.5 ) nanowires have been synthesized via a simple synthetic route using titanate nanowires as a precursor. The nanowires are highly crystalline and have been used for the first time as the anode material in a rechargeable lithium-ion battery. The battery has exhibited a highly reversible charge-discharge capacity and excellent cycling stability, even at a current density as high as 3.2 A g À1 . This result can be attributed to the intrinsic characteristics of spinel Li 2 MTi 3 O 8 nanowires. A three-dimensional network could provide a diffusion space for lithium ion insertion into and extraction from the anode material, resulting in very good cycle performance, even at a high rate.

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