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Liposomes are known to be promising nanoparticles (NPs) for drug delivery applications. Among different types of self-assembled NPs, liposomes stand out for their non-toxic nature, and their possession of dual hydrophilic-hydrophobic domains. Advantages of liposomes include the ability to solubilize hydrophobic drugs, the ability to incorporate different hydrophilic and lipophilic drugs at the same time, lessening the exposure of host organs to potentially toxic drugs and allowing modification of the surface by a variety of different chemical groups. This modification of the surface, or of the individual constituents, may be used to achieve two important goals. Firstly, ligands for active targeting can be attached that are recognized by cognate receptors over-expressed on the target cells of tissues. Secondly, modification can be used to impart a stimulus-responsive or "smart" character to the liposomes, whereby the cargo is released on demand only when certain internal stimuli (pH, reducing agents, specific enzymes) or external stimuli (light, magnetic field or ultrasound) are present. Here, we review the field of smart liposomes for drug delivery applications.

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A possible strategy to give a simultaneous boost to the energy and power attributes of the current generation of lithium‐ion batteries is developing thick porous electrodes with a high loading of active material alongside optimal percolation networks for the ions and electrons. However high the insertion capacity and kinetics of the single particle lithium‐insertion materials, the energy and power density of the cell can be capped by the ionic and electronic transport limitations in the porous electrode. In this work, a physical picture grounded in experiment and theory is proposed to spotlight and quantify the pivotal role of the micro‐scale porosity and active‐material loading in determining the tortuosity, effective transport properties, and performance limitations of porous electrodes. The outcome is a phenomenological picture coupled with a theoretical framework for the deconvolution of the relative shares of the electronic and ionic transport limitations over short and long ranges regarding the performance limitation of lithium‐ion batteries.

We introduce an efficient framework for investigating the heterogeneity in battery porous electrodes and its impacts on the performance and longevity of lithium-ion batteries. A phenomenological picture based on theory and experiment is presented to show how the spatial variations in the local porosity and thickness in a porous electrode result from a microscopically inhomogeneous slurry. A series of analogous bilayer LiNi0.6Mn0.2Co0.2O2 porous electrodes with different levels of heterogeneity, induced by a nonuniform distribution of carbon, is prepared as a model experimental system and established as a powerful tool in formalizing the concept of heterogeneity. We identify and distinguish between constructive and destructive heterogeneities as the two shades of nonuniformity in porous electrodes. Depending on the degree of heterogeneity, we observe up to 20% decline in the rate performance of the electrodes. The destructive and constructive heterogeneities in the analogous electrodes are manifested as 5-fold increase and 2-fold decrease, respectively, in the aging rate of Li4Ti5O12|LiNi0.6Mn0.2Co0.2O2 cells relative to that of a cell with a homogenous electrode after 200 cycles at 1 C.

In situ nitrogen doping of aluminum phosphate has been investigated in two dierent plasma enhanced atomic layer deposition (PE-ALD) processes. The rst method consisted of the combination of trimethyl phosphate plasma (TMP*) with a nitrogen plasma and trimethyl aluminum (TMA), i.e. TMP* -N 2 * -TMA. The second method replaces TMP* with a diethylphosphoramidate plasma (i.e. DEPA* -N 2 * -TMA), of which the amine group could further aid nitrogen doping and/or eliminate the need for a nitrogen plasma step. 1At a substrate temperature of 320 • C, the TMP*-based process showed saturated growth (0.8 nm/cycle) of a nitrogen doped (approximately 8 at.%) Al phosphate, while the process using DEPA* showed a similar amount of nitrogen but a signicantly higher growth rate (1.4 nm/cycle). In the latter case, nitrogen doping could also be achieved without the nitrogen plasma, but this leads to a high level of carbon contamination.Both lms were amorphous as-deposited, while X-ray diraction peaks related to AlPO 4 appeared after annealing in a He atmosphere. For high coating thickness (> 2 nm), a signicant increase in the Li-ion transmittance was found after nitrogen doping, although the coating has to be electrochemically activated.At lower thickness scales, such activation was not needed and nitrogen doping was found to double the eective transversal electronic conductivity. For the eective transversal ionic conductivity, no conclusive dierence was found. When a lithium nickel manganese cobalt oxide (NMC) powder is coated with one ALD cycle of N-doped Al phosphate, the rate capability and the energy eciency of the electrode improves.

Liposomes are known to be promising nanoparticles (NPs) for drug delivery applications. Among different types of self-assembled NPs, liposomes stand out for their non-toxic nature, and their possession of dual hydrophilic-hydrophobic domains. Advantages of liposomes include the ability to solubilize hydrophobic drugs, the ability to incorporate different hydrophilic and lipophilic drugs at the same time, lessening the exposure of host organs to potentially toxic drugs and allowing modification of the surface by a variety of different chemical groups. This modification of the surface, or of the individual constituents, may be used to achieve two important goals. Firstly, ligands for active targeting can be attached that are recognized by cognate receptors overexpressed on the target cells of tissues. Secondly, modification can be used to impart a stimulusresponsive or "smart" character to the liposomes, whereby the cargo is released on demand only when certain internal stimuli (pH, reducing agents, specific enzymes) or external stimuli (light, magnetic field or ultrasound) are present. Here, we review the field of smart liposomes for drug delivery applications.

No abstract