effect), a lower pH value, as well as a high level of oxidative stress. [4-9] Especially, the overproduction of reactive oxygen species (ROS) induces a serious oxidative stress, which is strongly implicated to various tumors. [8,9] In addition, a high ROS level is also considered to be an endpoint of the alteration of several important metabolic pathways in tumors. [8-11] Thus, modulation of the intratumor ROS level, either by scavenging ROS or increasing ROS, is a promising approach to anticancer therapy and ROS-related biomedical fields. [10-19] Recently, nanomaterial-enabled biocatalytic chemodynamic therapy has been demonstrated as a promising method for therapeutic intervention in a variety of tumors. [11-16,20] Through this biocatalytic tumor therapy, intratumor H 2 O 2 can be converted into toxic hydroxyl radicals (• OH) with the help of catalysts that can then induce tumor cell apoptosis and death through oxidative damage to various biomacromolecules, including DNA, lipids, and proteins. Nevertheless, the relatively deficient intratumoral H 2 O 2 level significantly lowers the biocatalytic therapeutic efficiency. [21-27] Thus, the focus has been on increasing the intratumoral H 2 O 2 level through oxidization of intratumoral molecules Catalytic generation of reactive oxygen species has been developed as a promising methodology for tumor therapy. Direct O 2 •− production from intratumor oxygen exhibits exceptional tumor therapeutic efficacy. Herein, this therapy strategy is demonstrated by a pH-responsive hybrid of porous CeO 2 nanorods and sodium polystyrene sulfonate that delivers high oxidative activity for O 2 •− generation within acidic tumor microenvironments for chemodynamic therapy and only limited oxidative activity in neutral media to limit damage to healthy organs. The hydrated polymer-nanorod hybrids with large hydrodynamic diameters form nanoreactors that locally trap oxygen and biological substrates inside and improve the charge transfer between the catalysts and substrates in the tumor microenvironment, leading to enhanced catalytic O 2 •− production and consequent oxidation. Together with successful in vitro and in vivo experiments, these data show that the use of hybrids provides a compelling opportunity for the delivery selective chemodynamic tumor therapy.

Although AgInS as one kind of ternary chalcogenides has been extensively investigated due to its band-edge positions meeting the thermodynamic requirement for water photosplitting, very little attention has been focused on the crystallinity and facet effects of AgInS on its photocatalytic activity. Herein, a facile hydrothermal route was developed to fabricate regular single-crystalline AgInS octahedrons with only {111} facets exposed. Also, the effects of the hydrothermal reaction conditions on the composition, crystal phase, crystallinity, and morphology of the obtained AgInS products (hereafter denoted as AIS-x, where x represents the pH value of the reaction solution) were investigated, and it was found that the accurately released S ions from the thermal decomposition of thioacetamide (TAA) is the central factor for the nucleation and growth of the AgInS octahedrons. The experimental results indicate that the resultant regular AgInS octahedrons (AIS-10.6) exhibit the best photocatalytic activity for H production among those AgInS products, and the higher crystallinity and fewer defects of the AgInS octahedrons compared to the other AgInS products can retard the photogenerated charge recombination, while those indium atoms with higher density in the exposed {111} facets might be beneficial for the photocatalytic H production reaction by acting as active sites to promote the charge separation and transfer processes. The results presented here provide new insights into the significance of crystallinity and exposed facets in the visible-light-responsive activity of AgInS, thus paving new ways into the design and synthesis of high-performance, cost-effective AgInS photocatalysts for H production.

Ca 2+ plays critical roles in the development of diseases, whereas existing various Ca regulation methods have been greatly restricted in their clinical applications due to their high toxicity and inefficiency. To solve this issue, with the help of Ca overexpressed tumor drug resistance model, the phytic acid (PA)-modified CeO 2 nano-inhibitors have been rationally designed as an unprecedentedly safe and efficient Ca 2+ inhibitor to successfully reverse tumor drug resistance through Ca 2+ negative regulation strategy. Using doxorubicin (Dox) as a model chemotherapeutic drug, the Ca 2+ nano-inhibitors efficiently deprived intracellular excessive free Ca 2+ , suppressed P-glycoprotein (P-gp) expression and significantly enhanced intracellular drug accumulation in Dox-resistant tumor cells. This Ca 2+ negative regulation strategy improved the intratumoral Dox concentration by a factor of 12.4 and nearly eradicated tumors without obvious adverse effects. Besides, nanocerias as pH-regulated nanozyme greatly alleviated the adverse effects of chemotherapeutic drug on normal cells/organs and substantially improved survivals of mice. We anticipate that this safe and effective Ca 2+ negative regulation strategy has potentials to conquer the pitfalls of traditional Ca inhibitors, improve therapeutic efficacy of common chemotherapeutic drugs and serves as a facile and effective treatment platform of other Ca 2+ associated diseases. Electronic Supplementary Material Supplementary material (further details of the XRD pattern of CeO 2 , TEM images, XPS spectra, cellular uptake study, cytotoxicity data, apoptosis study, biodistribution, and biosecurity of nanocerias in vivo , etc.) is available in the online version of this article at 10.1007/s12274-022-4069-0.

Selective hydrogenation of halonitrobenzenes into haloanilines represents a green process to replace the environmentally unfriendly non-catalytic chemical reduction process in industry. However, this transformation often suffers from serious dehalogenation due to the easy break of carbon-halogen bonds on metal surfaces. Modulations of the electronic structure of the supported Pd nanoparticles on Lewis-basic layered double hydroxides have been demonstrated to promote catalytic activity and selectivity for hydrogenation of halonitrobenzenes into haloanilines. Mechanism studies suggest that Pd with the enhanced electron density not only improves the capability for hydrogen activation, but also generates the partially negative-charged hydrogen species to suppress the electrophilic attack on the carbon-halogen bond and avoid the dehalogenation.