Unraveling the Ion Uptake Capacitive Deionization of Sea- and Highly Saline-Water by Sulfur and Nitrogen Co-Doped Porous Carbon Modified with Molybdenum Sulfide

In parallel to the depletion of potable water reservoirs, novel technologies have been developed for seawater softening, as it is the most abundant source for generating deionized water. Although salt removal at subosmotic pressures and ambient temperatures by applying low-operating potentials with high energy efficiency made capacitive deionization (CDI) an advantageous water-softening process, its practical application is limited by insufficient ion removal capacity and low concentration influent. The performance of a CDI system is in progress with engineering the electrode active materials, also facilitating the advance design in highly saline- and seawater study. Herein, an innovative strategy was developed to provide high-performance CDI systems based on efficient and electrochemical ion-uptake active materials with a simple initial preparation. Nitrogen-doped porous carbons (N-pCs) received benefits from a high specific surface area and good surface wettability. The N-pCs were modified with molybdenum oxide/sulfide intercalative array and developed as CDI electrode active materials for desalination of both low/medium saline- and seawater. The MoS2/S,N-pC electrode materials exhibited perfect optimized salt adsorption capacity (SACs) of 47.9 mg g-1 when compared to N-pC (37.9 mg g-1) and MoO3/N-pC (39.6 mg g-1) counterparts at 1.4 V in a 750 ppm NaCl solution. In addition, the assembled CDI cells exhibited reasonable cycle stability and retained 96.7% of their initial SAC in continuous CDI cycles for 128,000 s. The fabricated CDI cell rendered an excellent salt removal efficiency (SRE, %) of 13.34% from the real seawater sample at 1.2 V. In detail, the SRE % of the NaCl, KCl, MgCl2, and CaCl2 soluble salts with respect to seawater sample exhibited a remarkable SRE % of 30.8%, 36%, 32.6%, and 19.3%, respectively. These SRE % values (>13.34%) provide convincing evidence on the reasonable ion uptake capability of the fabricated CDI cells for removing Na+, K+, Mg2+, and Ca2+ ions compared to other soluble component. The advanced cell design parallel to the promising outcomes provided herein makes these CDI systems immensely propitious for efficient water softening.

Combination therapy to overcome ferroptosis resistance by biomimetic self-assembly nano-prodrug

Ferroptosis has emerged as a potent form of no-apoptotic cell death that offers a promising alternative to avoid the chemoresistance of apoptotic pathways and serves as a vulnerability of cancer. Herein, we have constructed a biomimetic self-assembly nano-prodrug system that enables the co-delivery of gefitinib (Gefi), ferrocene (Fc) and dihydroartemisinin (DHA) for the combined therapy of both ferroptosis and apoptosis. In the tumor microenvironment, this nano-prodrug is able to disassemble and trigger drug release under high levels of GSH. Interestingly, the released DHA can downregulate GPX4 level for the enhancement of intracellular ferroptosis from Fc, further executing tumor cell death with concomitant chemotherapy by Gefi. More importantly, this nano-prodrug provides highly homologous targeting ability by coating related cell membranes and exhibits outstanding inhibition of tumor growth and metastasis, as well as no noticeable side-effects during treatments. This simple small molecular self-assembled nano-prodrug provides a new reasonably designed modality for ferroptosis-combined chemotherapy.

Mechanism Regulating Self-Intercalation in Layered Materials

Recent experimental breakthrough demonstrated a powerful synthesis approach for intercalating the van der Waals gap of layered materials to achieve property modulation, thereby opening an avenue for exploring new physics and devising novel applications, but the mechanism governing intercalant assembly patterns and properties remains unclear. Based on extensive structural search and energetics analysis by ab initio calculations, we reveal a Sabatier-like principle that dictates spatial arrangement of self-intercalated atoms in transition metal dichalcogenides. We further construct a robust descriptor quantifying that strong intercalant-host interactions favor a monodispersing phase of intercalated atoms that may exhibit ferromagnetism, while weak interactions lead to a trimer phase with attenuated or quenched magnetism, which further evolves into tetramer and hexagonal phases at increasing intercalant density. These findings elucidate the mechanism underpinning experimental observations and paves the way for rational design and precise control of self-intercalation in layered materials.

The versatile family of molybdenum oxides: synthesis, properties, and recent applications

The family of molybdenum oxides has numerous advantages that make them strong candidates for high-value research and various commercial applications. The variation of their multiple oxidation states allows their existence in a wide range of compositions and morphologies that converts them into highly versatile and tunable materials for incorporation into energy, electronics, optical, and biological systems. In this review, a survey is presented of the most general properties of molybdenum oxides including the crystalline structures and the physical properties, with emphasis on present issues and challenging scientific and technological aspects. A section is devoted to the thermodynamical properties and the most common preparation techniques. Then, recent applications are described, including photodetectors, thermoelectric devices, solar cells, photo-thermal therapies, gas sensors, and energy storage.