Upconversion nanoparticle (UCNP)-mediated photodynamic therapy has shown great effectiveness in increasing the tissue-penetration depth of light to combat deep-seated tumors. However, the inevitable phototoxicity to normal tissues resulting from the lack of tumor selectivity remains as a major challenge. Here, the development of tumor-pH-sensitive photodynamic nanoagents (PPNs) comprised of self-assembled photosensitizers grafted pH-responsive polymeric ligands and UCNPs is reported. Under neutral pH conditions, photosensitizers aggregated in the PPNs are self-quenched; however, upon entry into a tumor microenvironment with lower pH, the PPNs not only exhibit enhanced tumor-cell internalization due to charge reversal but also are further disassembled into well-dispersed nanoparticles in the endo/lysosomes of tumor cells, enabling the efficient activation of photosensitizers. The results demonstrate the attractive properties of both UCNP-mediated deep-tissue penetration of light and high therapeutic selectivity in vitro and in vivo.

Although metallic nanomaterials with high X-ray attenuation coefficients have been widely used as X-ray computed tomography (CT) contrast agents, their intrinsically poor biodegradability requires them to be cleared from the body to avoid any potential toxicity. On the other hand, extremely small-sized nanomaterials with outstanding renal clearance properties are not much effective for tumor targeting because of their too rapid clearance in vivo. To overcome this dilemma, here we report on the hollow bismuth subcarbonate nanotubes (BNTs) assembled from renal-clearable ultrasmall bismuth subcarbonate nanoclusters for tumor-targeted imaging and chemoradiotherapy. The BNTs could be targeted to tumors with high efficiency and exhibit a high CT contrast effect. Moreover, simultaneous radio- and chemotherapy using drug-loaded BNTs could significantly suppress tumor volumes, highlighting their potential application in CT imaging-guided therapy. Importantly, the elongated nanotubes could be disassembled into isolated small nanoclusters in the acidic tumor microenvironment, accelerating the payload release and kidney excretion. Such body clearable CT contrast agent with high imaging performance and multiple therapeutic functions shall have a substantial potential for biomedical applications.

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Hierarchical hollow structure ZnO (CZ-400) was synthesized successfully by a facile homogeneous precipitation method. Morphology, structure, and optical properties of the as-prepared CZ-400 were characterized by different techniques. The mentioned product possessed hollow core and hierarchical shell morphology, and grew well-crystallinity with high surface area. The CZ-400 exhibited adsorption capacity and photocatalyst activity toward congo red (CR) higher than those of TiO 2 P25 and commercial ZnO. This is attributed to the hierarchical structure of CZ-400, which provides the improved charge transport and the reduced recombination rate of photogenerated electron−hole pairs. In addition, the combinatorial effect of adsorption and photodegradation reflected the importance of adsorption in the enhanced photoreactivity. The results indicated that CZ-400 is a potential catalyst and adsorbent material for removal of CR from water samples.

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In this paper, we grew the vanadium-doped nickel nitride porous nanosheet arrays supported on NF, V-Ni3N/NF, which displays efficient catalytic performance for urea electrolysis with energy-saving H2 production.

Metal oxides can deliver high capacity to Liion batteries, surpassing conventional graphite, but they suffer from a huge volume change during charging− discharging and poor cycle life. Herein, we merge the dual strategies of 3D-network support and sandwiching design to tackle such issue. We develop a skillful O 2 −NH 3 reactive pyrolysis of cellulose, where the preoxidation and the aminolysis result in the spatially separated charring of cellulose chains. A cellulose fiber is wonderfully converted into several ultrathin twisted graphenic sheets instead of a dense carbon fiber, and consequently, a cellulose paper is directly transformed into a porous flexible carbon paper with high surface area and conductivity (denoted as CP). CP is further fabricated as a 3D-network support into the hybrid CP@Fe 3 O 4 @RGO, where RGO is reduced graphene oxide added for sandwiching Fe 3 O 4 particles. As a binder-free free-standing anode, CP@Fe 3 O 4 @RGO effectively fastens Fe 3 O 4 and buffers the volume changes on cycling, which stabilizes the passivating layer and lifts the Coulombic efficiency. The anode thus presents an ultralong cycle life of >2000 running at a high capacity level of 1160 mAh g −1 . It additionally facilitates electron and ion transports, boosting the rate capability. CP and CP@Fe 3 O 4 @RGO represent a technological leap underpinning next-generation long-life high-capacity high-power batteries.