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Molecular electronic control over plasmons offers a promising route for on-chip integrated molecular plasmonic devices for information processing and computing. To move beyond the currently available technologies and to miniaturize plasmonic devices, molecular electronic plasmon sources are required. Here, we report on-chip molecular electronic plasmon sources consisting of tunnel junctions based on self-assembled monolayers sandwiched between two metallic electrodes that excite localized plasmons, and surface plasmon polaritons, with tunnelling electrons. The plasmons originate from single, diffraction-limited spots within the junctions, follow power-law distributed photon statistics, and have well-defined polarization orientations. The structure of the self-assembled monolayer and the applied bias influence the observed polarization. We also show molecular electronic control of the plasmon intensity by changing the chemical structure of the molecules and by bias-selective excitation of plasmons using molecular diodes.S urface plasmon polaritons (SPPs) confine and enhance local electromagnetic fields near surfaces of metallic nanostructures at optical frequencies and have the ability to propagate along subdiffractive metallic waveguides, thereby opening up new perspectives for integrated optoelectronic circuits at the nanoscale 1-4 . However, almost all these applications use large external light sources such as monochromatic lasers. To minimize the size of the light sources and ultimately the size of the plasmonic devices, plasmons have been excited on-chip using electrically driven light sources such as (organic) light-emitting diodes (LEDs) 5-8 , laser diodes 9 , silicon spheres 10 and single carbon nanotubes 11 instead of bulky lasers. Surface plasmons have also been directly excited by tunnelling electrons in metal-insulator-metal junctions based on metal oxides 12-14 or scanning tunnelling microscopes (STMs) using vacuum or molecular tunnelling barriers [15][16][17][18][19][20][21][22][23][24][25] . During the tunnelling process, most of the electrons tunnel elastically, but some tunnel inelastically and couple to a plasmon mode. Direct excitation of plasmons by tunnelling electrons is attractive because not only is no background light generated but potentially it is also fast 26 (on the timescale of quantum tunnelling) as no slow electron-hole recombination processes are required as is the case for electroluminescent (nano)light sources 5-11 . Here, we report a direct electronic plasmon source based on molecular tunnel junctions operating via throughmolecular-bond tunnelling, where the plasmonic properties can be electrically controlled at the molecular level (without the need for optical antennas 27,28 ).In molecular electronic devices, the tunnelling barrier height is defined by the electronic energy levels of the molecule(s) bridging two electrodes. The tunnelling barrier width is defined by the length of the bridging molecule. Hence, the tunnelling gaps in molecular electronic devices are always exact...

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Herein is reported a novel green process involving natural l-tartaric acid leaching, developed for the sustainable recovery of Mn, Li, Co, and Ni from spent lithium-ion batteries (LIBs). Operating conditions affecting the leaching efficiencies of Mn, Li, Co, and Ni, including the concentrations of l-tartaric acid (C4H6O6) and hydrogen peroxide (H2O2), pulp density, temperature, and leaching time, were investigated. The leaching efficiencies were 99.31% for Mn, 99.07% for Li, 98.64% for Co, and 99.31% for Ni under the optimized conditions (4 vol% H2O2, 2 M l-tartaric acid, 17 g/L pulp density, 70 °C, and 30 min). The leaching mechanism was studied preliminarily based on the structure of l-tartaric acid. The kinetics data for the leaching of Mn, Li, Co, and Ni fit best to the shrinking-core model of chemical control. For the first stage, the activation energies (E as) for the leaching of Mn, Li, Co, and Ni were 66.00, 54.03, 58.18, and 73.28 kJ/mol, respectively. For the second stage, the E as for the leaching of Mn, Li, Co, and Ni were 55.68, 53.86, 58.94, and 47.78 kJ/mol, respectively. The proposed hydrometallurgical process was found to be simple, efficient, and environmentally friendly.

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In recent years, stimulating the host immune system to create a promising antitumor immune therapy has been demonstrated to control metastatic tumor growth. [1] Research enthusiasm has been fueled by recent clinical successes in which antibodies were used to block immune inhibitory pathways, specifically the axis between programmed cell death protein 1 (PD-1) and its ligand 1 (PD-L1). [2] However, therapeutic antibodies exhibit several disadvantages, such as limited tissue and tumor penetration, very long half-life time, immunogenicity, and costly production. Moreover, the current PD-1/PD-L1 axis-directed monoclonal antibodies lead to a tumor response only in a fraction of cases and tumor types. [3] Therefore, the application of alternative, nonantibody-based agents to inhibit PD-1/ PD-L1 axis is currently a new goal within the field. [4] The development of organic smallmole cule inhibitors is expected to introduce a number of advantages in the field of PD-1/PD-L1 immune checkpoint Targeting programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) immunologic checkpoint blockade with monoclonal antibodies has achieved recent clinical success in antitumor therapy. However, therapeutic antibodies exhibit several issues such as limited tumor penetration, immunogenicity, and costly production. Here, Bristol-Myers Squibb nanoparticles (NPs) are prepared using a reprecipitation method. The NPs have advantages including passive targeting, hydrophilic and nontoxic features, and a 100% drug loading rate. BMS-202 is a small-molecule inhibitor of the PD-1/PD-L1 interaction that is developed by BMS. Transfer of BMS-202 NPs to 4T1 tumor-bearing mice results in markedly slower tumor growth to the same degree as treatment with anti-PD-L1 monoclonal antibody (α-PD-L1). Consistently, the combination of Ce6 NPs with BMS-202 NPs or α-PD-L1 in parallel shows more efficacious antitumor and antimetastatic effects, accompanied by enhanced dendritic cell maturation and infiltration of antigen-specific T cells into the tumors. Thus, inhibition rates of primary and distant tumors reach >90%. In addition, BMS-202 NPs are able to attack spreading metastatic lung tumors and offer immune-memory protection to prevent tumor relapse. These results indicate that BMS-202 NPs possess effects similar to α-PD-L1 in the therapies of 4T1 tumors. Therefore, this work reveals the possibility of replacing the antibody used in immunotherapy for tumors with BMS-202 NPs.The ORCID identification number(s) for the author(s) of this article can be found under https://doi.

Excess infrared (IR) absorption spectroscopy, a new concept brought forward by applying the idea of excess thermodynamic functions to infrared spectroscopy, is shown to be a potential method to study hydrogen bonds. It can be applied to enhance spectral resolution of complexed IR bands, to evaluate nonideality of liquid mixtures, and to estimate selective molecular interactions. The sign of the excess infrared absorption coefficient is also of importance in providing information on molecular interactions. The results demonstrate that excess infrared absorption spectroscopy can unveil new information on hydrogen bonding in condensed phases.

Atomistic molecular dynamics simulations have been performed to explore the effect of interfacial bonding on the interphase properties of a nanocomposite system that consists of a silica nanoparticle and the highly cross-linked epoxy matrix. For the structural properties, results show that interfacial covalent bonding can broaden the interphase region by increasing the radial effect range of fluctuated mass density and oriented chains, as well as strengthen the interphase region by improving the thermal stability of interfacial van der Waals excluded volume and reducing the proportion of cis conformers of epoxy segments. The improved thermal stability of the interphase region in the covalently bonded model results in an increase of ∼21 K in the glass transition temperature (Tg) compared to that of the pure epoxy. It is also found that interfacial covalent bonding mainly restricts the volume thermal expansion of the model at temperatures near or larger than Tg. Furthermore, investigations from mean-square displacement and fraction of immobile atoms point out that interfacial covalent and noncovalent bonding induces lower and higher mobility of interphase atoms than that of the pure epoxy, respectively. The obtained critical interfacial bonding ratio when the interphase and matrix atoms have the same mobility is 5.8%. These results demonstrate that the glass transitions of the interphase and matrix will be asynchronous when the interfacial bonding ratio is not 5.8%. Specifically, the interphase region will trigger the glass transition of the matrix when the ratio is larger than 5.8%, whereas it restrains the glass transition of the matrix when the ratio is smaller than 5.8%.