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2D FeS₂has the potential to convert ambient radiofrequency electromagnetic radiation signals into usable energy, which can be utilized to power portable and wearable electronic devices. 

Abstract Radiofrequency (RF) heating is a new, less invasive alternative to invasive heating methods that use nanoparticles for tumour therapy. But pinpoint local heating is still hard. Molecular interactions form a hybrid structure with unique electrical characteristics that enable RF heating in this work, which explores RF heating in a biological cell (yeast)‐2D FeS₂system. Substantial processes have been uncovered via experimental investigations and density functional theory (DFT) computations. At 3 W and 50 MHz, RF heating reaches 54°C in 40 s, which is enough to kill yeast cells, while current‐voltage measurements reveal ionic diode‐like properties. Interactions between yeast lipid molecules and 2D FeS_k, as shown by density‐functional theory calculations, cause an imbalance in the distribution of charges and the creation of polar, conductive channels. Insights into biological heating applications based on radio frequency (RF) technology are offered by this work, which lays forth a framework for investigating 2D material‐biomolecule interactions. 

Abstract Atomically thin, few‐layered membranes of oxides show unique physical and chemical properties compared to their bulk forms. Manganese oxide (Mn₃O₄) membranes are exfoliated from the naturally occurring mineral Hausmannite and used to make flexible, high‐performance nanogenerators (NGs). An enhanced power density in the membrane NG is observed with the best‐performing device showing a power density of 7.99 mW m⁻²compared to 1.04 µW m⁻²in bulk Mn₃O₄. A sensitivity of 108 mV kPa⁻¹for applied forces <10 N in the membrane NG is observed. The improved performance of these NGs is attributed to enhanced flexoelectric response in a few layers of Mn₃O₄. Using first‐principles calculations, the flexoelectric coefficients of monolayer and bilayer Mn₃O₄are found to be 50–100 times larger than other 2D transition metal dichalcogenides (TMDCs). Using a model based on classical beam theory, an increasing activation of the bending mode with decreasing thickness of the oxide membranes is observed, which in turn leads to a large flexoelectric response. As a proof‐of‐concept, flexible NGs using exfoliated Mn₃O₄membranes are made and used in self‐powered paper‐based devices. This research paves the way for the exploration of few‐layered membranes of other centrosymmetric oxides for application as energy harvesters. 

Abstract Quantum dots encompass a broad spectrum of optical, catalytic, and electrochemical properties bringing in novel applications in catalysis, imaging, displays, and optoelectronics. Herein, the unanticipated broad‐spectrum light absorption and high fluorescence quantum yield in fluorinated boron nitride (FBN) quantum dots are discussed. A heterostructure of FBN quantum dots with a wide‐bandgap semiconductor, titania nanotube arrays, exhibits high photocatalytic activity as evidenced by high external quantum efficiency extending from ultraviolet to green region of the solar spectrum (≈24% at 400 nm). The high activity is confirmed using photoelectrochemical hydrogen evolution experiments. Further, it is demonstrated that high fluorescence quantum yield could be tapped for the detection of glycolytic activity in cancer cells compared to normal cells. This finding could shift the paradigm of molecular detection using quantum dots. The 0D structure and the gap states introduced through fluorination are believed to be responsible for these unprecedented characteristics of boron nitride.