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Resveratrol, a natural polyphenol, exhibits beneficial health properties and has been touted as a potential anti-tumor agent. Here, we demonstrate potent anti-cancer effects of carbon dots (C-dots) synthesized from resveratrol. The mild synthesis conditions retained resveratrol functional moieties upon the carbon dots’ (C-dots) surface, an important requisite for achieving specificity toward cancer cells and biological activities. Indeed, the disruptive effects of the resveratrol-C-dot were more pronounced in several cancer cell types compared to normal cells, underscoring targeting capabilities of the C-dots, a pertinent issue for the development of cancer therapeutics. In particular, we observed impairment of mitochondrial functionalities, including intracellular calcium release, inhibition of cytochrome-C oxidase enzyme activity, and mitochondrial membrane perturbation. Furthermore, the resveratrol C-dots were more potent than either resveratrol molecules alone, known anti-cancer polyphenolic agents such as curcumin and triphenylphosphonium, or C-dots prepared from different carbonaceous precursors. This study suggests that resveratrol-synthesized C-dots may have promising therapeutic potential as anti-cancer agents.

Exposure to constituent hazardous chemicals in medical products has become a threat to environmental health across the globe. Excessive medication and the mishandling of pharmaceutical drugs can lead to the increased presence of chemicals in the aquatic environment, causing water pollution. Only a few nanomaterials exist for the detection of these chemicals and they are limited in use due to their adverse toxicity, instability, cost, and low aqueous solubility. In contrast, carbon dots (C-dots), a member of the family of carbon-based nanomaterials, have various beneficial properties including excellent biocompatibility, strong photoluminescence, low photobleaching, tunable fluorescence, and easy surface modification. Herein, we summarize recent advancements in various synthetic strategies for high-quality tunable fluorescent C-dots. The root of fluorescence has been briefly explained viathe quantum confinement effect, surface defects, and molecular fluorescence. The surface functional moieties of C-dots have been investigated in depth to recognize the various types of pharmaceutical drugs that are used for the treatment of patients. The modulation of C-dot fluorescence in the course of their interactions with these drugs has been carefully explained. Different types of interaction mechanisms behind the C-dot fluorescence alteration have been discussed. Finally, the challenges and future perspectives of C-dots have been proposed for the vibrant field development of C-dot-based drug sensors.

Major challenges in the development of solid-state batteries using garnet-type solid-state electrolytes (SSEs) include suppressing dendrite growth, improving moisture stability, and reducing interfacial resistance. Prior attempts to remove surface impurities of SSEs through dry polishing caused high interfacial resistance that proves this method to be unviable. Further, several efforts on depositing thin-film protective layers on SSEs without understanding surface chemistry failed to demonstrate improved electrochemical performance. Here, we report the simultaneous removal of the surface impurities and protection of the SSE against air and moisture by regulating its surface chemistry. In situ X-ray photoelectron spectroscopy (XPS) studies revealed that primary surface contaminants such as lithium carbonate (Li2CO3) and lithium hydroxide on the SSE, Li6.5La3Zr1.5Ta0.5O12(LLZT), could be removed by either argon-ion sputtering at 227 °C or annealing at 777 °C in ultrahigh vacuum conditions. To protect the cleaned LLZT surface from further ambient contamination, in situ atomic layer deposition was used to deposit ∼3 nm-thick h-BN using tris(dimethylamino)borane and ammonia precursors at 450 °C. Intermittent XPS analysis confirmed the absence of Li2CO3formation and the stability of h-BN-coated LLZT pellets for over 2 months of exposure to atmospheric air and moisture. Electrochemical impedance spectroscopy studies revealed that an ultrathin layer of ∼3 nm h-BN drastically reduced the interfacial resistance from 1145 to 18 Ω cm2(∼65× reduction). Li plating/stripping studies revealed a constant polarization of 27 mV at a 0.5 mA cm–2current density over prolonged cycling and a high critical current density of 0.9 mA cm–2. An all-solid-state battery using a LiFePO4cathode exhibited a stable capacity of 130 mAh g–1for over 100 cycles and a negligible capacity fade-off of 0.11 mAh g–1per cycle at an average Coulombic efficiency of 98.4%.

Solid oxide electrolysis cells (SOECs) are devices that enable economically viable production of clean fuel such as hydrogen gas, which can be used in many industrial applications and serving as an energy carrier for renewable energy sources. Operation of SOEC at intermediate temperature (IT) range (400 to 600 °C) is highly attractive because many unexploited heat sources from industries can be utilized. Proton conducting SOECs based on barium–zirconium–cerate electrolytes show great potential for operating at this temperature range due to their high proton conductivity at reduced temperatures. In this study, a new tridoped BaCe0.5Zr0.2Y0.1Yb0.1Gd0.1O3−δ(BCZYYbGd) electrolyte with very high chemical stability and proton conductivity is coupled with a PrNi0.5Co0.5O3−δsteam electrode and a Ni-BCYYbGd hydrogen electrode for IT-SOEC operation. The dopants of the electrolyte were carefully designed to obtain the optimum stability and conductivity for IT-SOEC. The BCYYbGd electrolyte was stable over 200 h at 50 vol % steam in argon and at 600 °C, and a very high electrolysis current density of 2.405 A cm–2was obtained at 600 °C and 1.6 V at 20 vol % of steam in argon. This system was also found to be highly reversible, exhibiting very high performance in SOFC mode and suggesting a potential candidate for next generation proton conducting electrolyte.

Understanding lithium dendrite propagation in solid-state electrolytes requires highly advanced techniques due to the challenges arising from the lack of characterization techniques to visualize the interior of a solid. In this work, a high-pressure in-situ cell was made to monitor the dynamic changes occurring within an All-Solid-State-Battery under cycling using multiple characterization techniques.