A narrow-bandgap RuI3 nanoplatform to synergize radiotherapy, photothermal therapy, and thermoelectric dynamic therapy for tumor eradication.

Therapeutic resistance is an essential challenge for nanotherapeutics. Herein, a narrow bandgap RuI3 nanoplatform has been constructed firstly to synergize radiotherapy (RT), photothermal therapy (PTT), and thermoelectric dynamic therapy (TEDT) for tumor eradication. Specifically, the photothermal performance of RuI3 can ablate tumor cells while inducing TEDT. Noteworthy, the thermoelectric effect is found firstly in RuI3, which can spontaneously generate an electric field under the temperature gradient, prompting carrier separation and triggering massive ROS generation, thus aggravating oxidative stress level and effectively inhibiting HSP-90 expression. Moreover, RuI3 greatly enhances X-ray deposition owing to its high X-ray attenuation capacity, resulting in a pronounced computed tomography imaging contrast and DNA damage. In addition, RuI3 possesses both catalase-like and glutathione peroxidase-like properties, which alleviate tumor hypoxia and reduce antioxidant resistance, further exacerbating 1O2 production during RT and TEDT. This integrated therapy platform combining PTT, TEDT, and RT significantly inhibits tumor growth. STATEMENT OF SIGNIFICANCE: RuI3 nanoparticles were synthesized for the first time. RuI3 exhibited the highest photothermal properties among iodides, and the photothermal conversion efficiency was 53.38 %. RuI3 was found to have a thermoelectric effect, and the power factor could be comparable to that of most conventional thermoelectric materials. RuI3 possessed both catalase-like and glutathione peroxidase-like properties, which contributed to enhancing the effect of radiotherapy.

Coregulation of Li/Li+ Spatial Distribution by Electric Field Gradient with Homogenized Li-Ion Flux for Dendrite-Free Li Metal Anodes.

Lithium (Li) metal batteries are highly sought after for their exceptional energy density. However, their practical implementation is impeded by the formation of dendrites and significant volume fluctuations in Li, which stem from the uneven distribution of Li-ions and uncontrolled deposition of Li on the current collector. Here, an amino-functionalized reduced graphene oxide covered with polyacrylonitrile (PrGN) film with an electric field gradient structure is prepared to deal with such difficulties. This novel current collector serves to stabilize Li-metal anodes by regulating Li-ion flux through vertically aligned channels formed by porous polyacrylonitrile (PAN). Moreover, the amino-functionalized reduced graphene oxide (rGN) acts as a three-dimensional (3D) host, reducing nucleation overpotential and accommodating volume expansion during cycling. The combination of the insulating PAN and conducting rGN creates an electric field gradient that promotes a bottom-up mode of Li electrodeposition and safeguards the anode from interfacial parasitic reactions. Consequently, the electrodes exhibit exceptional cycle life with stable voltage profiles and minimal hysteresis under high current densities and large areal capacities.

Bi nanoparticles confined in N,S co-doped carbon nanoribbons with excellent rate performance for sodium-ion batteries.

Bismuth (Bi) has emerged as a promising candidate for sodium-ion battery anodes because of its unique layered crystal structure, superior volumetric capacity, and high theoretical gravimetric capacity. However, the large volume expansion and severe aggregation of Bi during the alloying/dealloying reactions are extremely detrimental to cycling stability, which seriously hinders its practical application. To overcome these issues, we propose an effective synthesis of composite materials, encapsulating Bi nanoparticles in N,S co-doped carbon nanoribbons and composites with carbon nanotubes (N,S-C@Bi/CNT), using Bi2S3 nanobelts as templates. The uniform distribution of Bi nanoparticles and the structure of carbon nanoribbons can reduce the diffusion path of ions/electrons, efficiently buffer the large volume change and prevent Bi from aggregating during cycles. As expected, the N,S-C@Bi/CNT electrode shows superior sodium storage performance in half cells, including a high specific capacity (345.3 mA h g-1 at 1.0 A g-1), long cycling stability (1000 cycles), and superior rate capability (336.0 mA h g-1 at 10.0 A g-1).

Pseudopyrolysis of Metal-Organic Frameworks: A Synchronous Nucleation Mechanism to Synthesize Ultrafine Metal Compound Nanoparticles.

Metal-Organic frameworks (MOFs) are increasingly being investigated for the synthesis of carbon-supported metal-based ultrafine nanoparticles (UNPs). However, the collapse of the carbon framework and aggregation of metal particles in the pyrolysis process have severely hindered their stability and applications. Here, we report the synchronous nucleation pseudopyrolysis of MOFs to confine Fe/FeOx UNPs in intact porous carbon nanorods (IPCNs), revealed by in situ transmission electron microscopy experiments and ex situ structure analysis. The pseudopyrolysis mechanism enables strong physical and chemical confinement effects between UNPs and carbon by moderate thermal kinetics and abundant oxygen defects. Further, this strong confinement is greatly beneficial for subsequent chemical transformations to obtain different Fe-based UNPs and excellent electrochemical performance. As a proof of concept, the as-prepared FeSe UNPs in IPCNs show superior lithium storage performance with an ultrahigh and stable capacity of 815.1 mAh g-1 at 0.1 A g -1 and 379.7 mAh g-1 at 5 A g-1 for 1000 cycles.

Boosting Charge Transfer Via Heterostructure Engineering of Ti2 CTx /Na2 Ti3 O7 Nanobelts Array for Superior Sodium Storage Performance.

The poor conductivity, inert charge transmission efficiency, and irreversible Na+ trapping of Na2 Ti3 O7 result in retardant electrons/ions transportation and deficient sodium-ion storage efficiency, leading to sluggish reaction kinetics. To address these issues, an urchin-like Ti2 CTx /Na2 Ti3 O7 (Ti2 C/NTO) heterostructure sphere consisting of Ti2 C/NTO heterostructure nanobelts array is developed via a facile one-step in situ hydrothermal strategy. The Ti2 C/NTO heterostructure can obviously decrease Na+ diffusion barriers and increase electronic conductivity to improve reaction kinetics due to the built-in electric field effect and high-quantity interface region. In addition, the urchin-like vertically aligned nanobelts can reduce the diffusion distance of electrons and ions, provide favored electrolyte infiltration, adapt large volume expansion, and mitigate the aggregation to maintain structural stability during cycles, further enhancing the reaction kinetics. Furthermore, the Ti2 C/NTO heterostructure can effectively suppress many unwanted side reactions between reactive surface sites of NTO and electrolyte as well as irreversible trapping of Na+ . As a result, systematic electrochemical investigations demonstrate that the Ti2 C/NTO heterostructure as an anode material for record sodium-ion storage delivers the highest reversible capacity, the best cycling stability with 0.0065% decay rate for 4500 cycles at 2.0 A g-1 , and excellent rate capability of 172.1 mAh g-1 at 10.0 A g-1 .

Tailoring the Void Space Using Nanoreactors on Carbon Fibers to Confine SnS2 Nanosheets for Ultrastable Lithium/Sodium-Ion Batteries.

Herein, a rational design of SnS2 nanosheets confined into bubble-like carbon nanoreactors anchored on N,S doped carbon nanofibers (SnS2 @C/CNF) is proposed to prepare the self-standing electrodes, which provides tunable void space on carbon fibers for the first time by introducing hollow carbon nanoreactors. The SnS2 @C/CNF provides the stable support with greatly enhanced ion and electron transport, alleviates aggregation and volume expansion of SnS2 nanosheets, and promotes the formation of abundant exposed edges and active sites. The volume balance between SnS2 nanosheets and hollow carbon nanoreactors is reached to accommodate the expansion of SnS2 during cycles by controlling the thickness of SnO2 shells, which achieves the best space utilization. The doping of N,S elements enhances the wettability of the carbon nanofiber matrix to electrolyte and Li ions and further improves the electrical conductivity of the whole electrode. Thus, the SnS2 @C/CNF benefits greatly in structural stability and pseudocapacitive capacity for improved lithium/sodium storage performance. As a result of these improvements, the self-standing SnS2 @C/CNF film electrodes exhibit the highly stable capacity of 964.8 and 767.6 mAh g-1 at 0.2 A g-1 , and excellent capacity retention of 87.4% and 82.4% after 1000 cycles at high current density for lithium-ion batteries and sodium-ion batteries, respectively.

Tumor Microenvironment Responsive Biodegradable Fe-Doped MoOx Nanowires for Magnetic Resonance Imaging Guided Photothermal-Enhanced Chemodynamic Synergistic Antitumor Therapy.

Rational design of nanosystems that target tumor microenvironment have attracted widespread attention. However, it is still a great challenge to make a multifunctional nanoplatform that actively and selectively interacts with tumor microenvironment, without causing toxicity to surrounding normal tissues. Herein, the biodegradable Fe-doped MoOx (FMO) nanowires are designed as an anti-tumor nanoreagent that possesses great photothermal conversion ability (48.5%) and magnetic properties for T1 weighted magnetic resonance imaging (MRI). Also, FMO can be used as a chemodynamic therapy (CDT) reagent to effectively catalyze the decomposition of H2 O2 and produce hydroxyl radical (·OH). At the same time, the consumption of glutathione will also enhance the CDT effect. More importantly, FMO presents pH-dependent degradation behavior: rapid degradation at physiological pH, but relatively stable at acidic pH. In vivo anti-tumor experiment demonstrates that the FMO is able to effectively inhibit the tumor growth with minimal side effects. Generally speaking, these results indicate that the FMO has huge potential for MRI image-guided cancer therapy and promotes the clinical translation of nanodrugs.