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[Display omitted] • Catalysts have favorable ECSA, multiple active centers, and sufficient mass transport. • PtCo nanoparticles (about 2.5 nm) are uniformly distributed and firmly anchored in the matrix. • The synergistic effect of PtCo, Co 9 S 8 and Co-N strengthens the catalytic performance. • Strong chemical/electronic interactions enhance the anchoring of PtCo NPs on the carrier. • The catalysts exhibit more excellent ORR and HER performance than the Pt/C. The development of low-Pt bifunctional electrocatalysts with excellent performance for oxygen reduction reaction (ORR) and hydrogen evolution reaction (HER) is critical for the advancement of the hydrogen economy. Here, we have integrated low-loading Pt and Co metals into N, S doped porous carbon nanosheets to obtain composite catalysts encapsulating PtCo alloy nanoparticles (PtCo2@Co 9 S 8 / N -CNS and PtCo2@ N -CNS). The acquired PtCo nanoparticles, with dimensions of about 2.5 nm, are uniformly distributed and firmly anchored in N, S doped carbon nanosheets with large specific surface areas and rich pore structure, forming multiple active centers and effectively preventing the aggregation of metal nanoparticles. The PtCo2@Co 9 S 8 / N -CNS and PtCo2@ N -CNS display high ORR catalytic mass activity of 1.65 A mg Pt -1 and 1.01 A mg Pt -1 in 0.1 M HClO 4. The PtCo2@ N -CNS catalyst exhibits excellent HER performance in 0.5 M H 2 SO 4 , with a mass activity (at 50 mV) 4.3 times higher than that of Pt/C. The PtCo2@Co 9 S 8 / N -CNS and PtCo2@ N -CNS also exhibit stronger ORR and HER stability than Pt/C after accelerated durability tests. The superior catalytic activity performance of catalysts can be attributed to the synergistic effect of multiple active centers of PtCo, Co 9 S 8 and Co-N in the catalysts. The confinement of PtCo nanoparticles by Co metal and N, S doped porous nanosheets derived from graphitic carbon nitride (g-C 3 N 4) as the template, which can effectively prevent the corrosion and migration of the catalysts under acidic conditions, enhances the catalytic stability of the materials. This study provides a new perspective for the development of economical and efficient bifunctional low-Pt catalysts. [ABSTRACT FROM AUTHOR]

[Display omitted] The amplified oxidative stress strategy has been emerged as one promising method to enhance the chemodynamic therapy (CDT) efficacy due to the H 2 O 2 up-regulation and glutathione (GSH) down-regulation behavior in tumor cells. However, how to further achieve the satisfied CDT efficacy is still a big challenge. In this paper, the supramolecular nanovalves (SNs) with oxidative amplification agents cinnamaldehyde-(phenylboronic acid pinacol ester) conjugates (CA-BE) encapsulated inside were developed to accelerate and amplify the generation of ·OH and consumption of GSH while augmenting the CDT efficacy. SNs were obtained through ferrocene/Au modified mesoporous silica nanoparticles (MSN@Au-Fc) and active targeting β -cyclodextrin modified hyaluromic acid (HA-CD). After CD44 receptor-mediated cellular internalization, the CA-BE were released to elevate H 2 O 2 amount and consume GSH for the desired generation of higher cytotoxic hydroxyl radicals (·OH). Moreover, the NIR-activated MSN@Au-Fc can increase the temperature for the accelerated and amplified oxidative stress. As such, the therapeutic efficacy of our synthesized CA-BE and the accompanied hyperthermia were augmented toward synergistically inhibiting tumor growth. [ABSTRACT FROM AUTHOR]

[Display omitted] Triple-negative breast cancer (TNBC) is insensitive to conventional therapy due to its highly invasive nature resulting in poor therapeutic outcomes. Recent studies have shown multiple genes associated with ferroptosis in TNBC, suggesting an opportunity for ferroptosis-based treatment of TNBC. However, the efficiency of present ferroptosis agents for cancer is greatly restricted due to lack of specificity and low intracellular levels of H 2 O 2 in cancer cells. Herein, we report a nano-theranostic platform consisting of gold (Au)-iron oxide (Fe 3 O 4) Janus nanoparticles (GION@RGD) that effectively enhances the tumor-specific Fenton reaction through utilization of near-infrared (NIR) lasers, resulting in the generation of substantial quantities of toxic hydroxyl radicals (•OH). Specifically, Au nanoparticles (NPs) converted NIR light energy into thermal energy, inducing generation of abundant intracellular H 2 O 2 , thereby enhancing the iron-induced Fenton reaction. The generated •OH not only lead to apoptosis of malignant tumor cells but also induce the accumulation of lipid peroxides, causing ferroptosis of tumor cells. After functionalizing with the activity-targeting ligand RGD (Arg-Gly-Asp), precise synergistic treatment of TNBC was achieved in vivo under the guidance of Fe 3 O 4 enhanced T 2 -weighted magnetic resonance imaging (MRI). This synergistic treatment strategy of NIR-enhanced ferroptosis holds promise for the treatment of TNBC. [ABSTRACT FROM AUTHOR]

[Display omitted] • A new CoSe 2 -ZnSe@rGO composite with heterointerfaces is designed and synthesized. • The CoSe 2 -ZnSe@rGO composite behaves special structure characteristics. • The built-in electric field in the heterointerfaces is favorable for Na+ transfer. • The rGO could improve conductivity and alleviate volume variations of the active materials. • The CoSe 2 -ZnSe@rGO exhibits an enhanced coulombic efficiency and cycling stability. Transition metal selenides are promising anode candidates for sodium ion batteries (SIBs) because of their higher theoretical capacity and conductivity than metal oxides. However, the disadvantages of severe capacity degradation and poor magnification performance greatly limit their commercial applications. Herein, we have developed a new hollow bimetallic selenides (CoSe 2 -ZnSe)@reduced graphene oxide (rGO) composite with abundant heterointerfaces. The rGO could not only alleviate the volume variations of hollow CoSe 2 -ZnSe microspheres during cycling, but also improve the conductivity of composite. The presence of the heterointerfaces could help to accelerate ionic diffusion kinetics and improve electron transfer, resulting in the improved sodium storage performance. As an advanced anode for SIBs, the CoSe 2 -ZnSe@rGO exhibits an enhanced initial coulombic efficiency of 75.1% (65.2% of CoSe 2 @rGO), extraordinary rate capability, and outstanding cycling stability (540.3 mAh/g at 0.2 A/g after 150 cycles, and 395.2 mAh/g at 1 A/g after 600 cycles). The electrochemical mechanism was also studied by kinetic analysis, showing that the charging/discharging process of CoSe 2 -ZnSe@rGO is mostly related to a capacitive-controlled behavior. [ABSTRACT FROM AUTHOR]