Abstract: An electrochemical process, and related method and system to upgrade captured CO2 into value-added products. CO2 capture technologies based on chemisorption present the potential to lower net emissions of CO2 into the atmosphere. The use of alkali cations to tailor the electrochemical double layer allows achieving the valorization of chemisorbed CO2 in an aqueous amine-based electrolyte, by placing the CO2 of the amine-CO2 adduct sufficiently close to the site of an heterogeneous reaction at the working electrode. It is revealed, using electrochemical studies and in-situ surface-enhanced Raman spectroscopy, that a smaller double layer distance can correlate with improved activity for CO2 to CO from amine solutions.

Abstract: The present disclosure provides a method for facet-selective passivation on each crystal facet of colloidal nanocrystals via solution-phase ligand exchange process, thereby providing highly-passivated and colloidally-stable nanocrystal inks. This ligand exchange strategy separately addresses polar and non-polar facets precluding from deleterious nanocrystal aggregation in the colloid. The method involves the introduction of alkali metal organic complexes during metal halide conventional solution exchanges, and one specific example is Na+·Ac?. Alkali metal ions stabilize and passivate non polar facets whereas polar facets are passivated through metal halides. This strategy leads to a significant decrease in nanocrystal aggregation during and after ligand exchange, and to improved photophysical properties stemming from this. The resulting nanocrystal solid films exhibit improved stability, retain their absorption features, and have a minimized Stokes shift.

Abstract: Methods and systems for mRNA analysis and quantification of mRNA expression in cells are provided. An example method includes introducing a first capture probe and a second capture probe into the cells, the first capture probe and the second capture probe each configured to be complementary to a respective section of target mRNA within the cells, wherein binding of the first and second capture probes to the respective sections of the target mRNA results in tagging of the cells and causes the first and second capture probes to form clusters with each other. The first capture probe and the second capture probe are each bound to magnetic nanoparticles (MNPs) that, when trapped within the tagged cells, cause the tagged cells to be susceptible to magnetic forces. The method and system further include introducing the cells into a device configured to magnetically capture tagged cells.

Abstract: Aspects included herein include an electrolytic system for electrochemical reduction of carbon dioxide, the system comprising: a cathode comprising: a porous gas-diffusion membrane permeable to CO2; an electrocatalyst layer adjacent to a second side of the gas-diffusion membrane; the electrocatalyst layer comprising: an electrically conductive catalyst; and a selectivity-determining organic material attached to at least a portion of the electrically conductive catalyst; wherein: the organic material is formed of a plurality of oligomers; each oligomer comprises a plurality of covalently bonded base units; each base unit comprises at least one heterocyclic group having at least one nitrogen in its structure; and an anion exchange membrane adjacent to the electrocatalyst layer and positioned between the anode and the cathode; wherein anion exchange membrane is characterized by anion conductivity and the cathode is in ionic communication with the anode via the anion exchange membrane.

Abstract: A semiconductor nanocrystal particle represented by Chemical Formula 1 and having a full width at half maximum (FWHM) of less than or equal to about 30 nanometers (nm) in the emission wavelength spectrum is provided: AxA?(3+??x)D(2+?)E(9+?). ??Chemical Formula 1 In Chemical Formula 1, A is a first metal including Rb, Cs, or a combination thereof, A? is an organic substance derived from an ammonium salt, an organic material derived from an organic ligand, or an organic material including a combination thereof, D is a second metal including Sb, Bi, or a combination thereof E is Cl, Br, I, or a combination thereof, 1<x?3, ?1<?<1, 3+??x>0, ?1<?<1, and ?1<?<1.

Abstract: A semiconductor nanocrystal particle represented by Chemical Formula 1 and having a full width at half maximum (FWHM) of less than or equal to about 30 nanometers (nm) in the emission wavelength spectrum is provided: AxA?(3+??x)D(2+?)E(9+?).??Chemical Formula 1 In Chemical Formula 1, A is a first metal including Rb, Cs, or a combination thereof, A? is an organic substance derived from an ammonium salt, an organic material derived from an organic ligand, or an organic material including a combination thereof, D is a second metal including Sb, Bi, or a combination thereof E is Cl, Br, I, or a combination thereof, 1<x?3, ?1<?<1, 3+??x>0, ?1<?<1, and ?1<?<1.

Abstract: Disclosed herein are lattice-anchored materials that combine cesium lead halide perovskites with lead chalcogenide colloidal quantum dots (CQDs) that surprisingly exhibit stability exceeding that of the constituent materials. The CQDs keep the perovskite in its desired cubic phase, suppressing the transition to the undesired, lattice-mismatched, phases. These composite materials exhibit an order of magnitude enhancement in air stability for the perovskite, showing greater than six months' stability in room ambient as well as being stable for more than five hours at 200° C. in air. The perovskite prevents oxidation of the CQD surfaces and reduces the nanoparticles' agglomeration under 100° C. by a factor of five compared to CQD controls. The matrix-protected CQDs exhibit 30% photoluminescence quantum efficiency for a CQD solid emitting at infrared wavelengths.

Abstract: Disclosed is a quantum dot based solar cell device which includes a substrate, a light harvesting structure sandwiched between electrically conducing layers, with at least one electrically conducting layer being substantially transparent with the light harvesting structure being located on the substrate. The light harvesting structure includes a layer of semiconducting quantum dots, with this layer of semiconducting quantum dots including at least two distinct sets of semiconducting quantum dots which are homogenously mixed. One of the two distinct sets of semiconducting quantum dots has a first bandgap and the at least one other distinct set of semiconducting quantum dots has a second bandgap different from the first bandgap. Both sets of semiconducting quantum dots are passivated with any one or combination of halides and pseudo-halides.

Abstract: Disclosed herein are homogeneous CQD bulk homojunction solids prepared through a cascade surface modification (CSM) strategy. The CSM includes an initial halogenation step of CQD surfaces to attain an initial sufficient passivation; and a subsequent step that reprograms CQD surfaces with functional ligands to control the doping character and solubility properties of the resulting CQD inks. The resulting p-type and n-type CQDs exhibit a distinct potential difference, which induces a built-in electric field between the constituent classes of CQDs. By controlling the colloidal solubility of the inks, homogeneous CQD bulk homojunction films have been achieved, whereas it is shown that the use of prior ink strategies results in inhomogeneous films as a result of poor miscibility. The homogeneous CQD bulk homojunction films exhibit a 1.5-fold increase in the carrier diffusion length and outperforms previously-reported CQD solar cells, achieving a record PCE of 13.3%.

Abstract: The present disclosure provides a method for facet-selective passivation on each crystal facet of colloidal nanocrystals via solution-phase ligand exchange process, thereby providing highly-passivated and colloidally-stable nanocrystal inks. This ligand exchange strategy separately addresses polar and non-polar facets precluding from deleterious nanocrystal aggregation in the colloid. The method involves the introduction of alkali metal organic complexes during metal halide conventional solution exchanges, and one specific example is Na+.Ac?. Alkali metal ions stabilize and passivate non polar facets whereas polar facets are passivated through metal halides. This strategy leads to a significant decrease in nanocrystal aggregation during and after ligand exchange, and to improved photophysical properties stemming from this. The resulting nanocrystal solid films exhibit improved stability, retain their absorption features, and have a minimized Stokes shift.

Abstract: Perovskites have high density of vacancies which absorb oxygen molecules and upon illumination, transform them into superoxide species which react with perovskites to decompose them, preventing use of these materials in many photo-applications. The present disclosure provides ways for improving the stability of perovskites in air ambient by doping perovskites with metals such as lead, cadmium, zinc, manganese, iron, cobalt, nickel, copper and tin which decreases the density of vacancies in perovskites and significantly increases the lifetime of perovskites. Perovskite solar cells containing inorganic and organic ions such as Cs+, formamidinium and methylammonium cations, Pb2+, Br— and I— with these metal dopants exhibit stable efficiency within a month of storage in air ambient with the relative humidity of 50%.

Abstract: Aspects included herein include an electrolytic system for electrochemical reduction of carbon dioxide, the system comprising: a cathode comprising: a porous gas-diffusion membrane permeable to CO2; an electrocatalyst layer adjacent to a second side of the gas-diffusion membrane; the electrocatalyst layer comprising: an electrically conductive catalyst; and a selectivity-determining organic material attached to at least a portion of the electrically conductive catalyst; wherein: the organic material is formed of a plurality of oligomers; each oligomer comprises a plurality of covalently bonded base units; each base unit comprises at least one heterocyclic group having at least one nitrogen in its structure; and an anion exchange membrane adjacent to the electrocatalyst layer and positioned between the anode and the cathode; wherein anion exchange membrane is characterized by anion conductivity and the cathode is in ionic communication with the anode via the anion exchange membrane.

Abstract: A semiconductor nanocrystal particle represented by Chemical Formula 1 and having a full width at half maximum (FWHM) of less than or equal to about 30 nanometers (nm) in the emission wavelength spectrum is provided: AxA?(3+??x)D(2+?)E(9+?). ??Chemical Formula 1 In Chemical Formula 1, A is a first metal including Rb, Cs, or a combination thereof, A? is an organic substance derived from an ammonium salt, an organic material derived from an organic ligand, or an organic material including a combination thereof, D is a second metal including Sb, Bi, or a combination thereof E is Cl, Br, I, or a combination thereof, 1<x?3, ?1<?<1, 3+??x>0, ?1<?<1, and ?1<?<1.

Abstract: Methods and systems for mRNA analysis and quantification of mRNA expression in cells are provided. An example method includes introducing a first capture probe and a second capture probe into the cells, the first capture probe and the second capture probe each configured to be complementary to a respective section of target mRNA within the cells, wherein binding of the first and second capture probes to the respective sections of the target mRNA results in tagging of the cells and causes the first and second capture probes to form clusters with each other. The first capture probe and the second capture probe are each bound to magnetic nanoparticles (MNPs) that, when trapped within the tagged cells, cause the tagged cells to be susceptible to magnetic forces. The method and system further include introducing the cells into a device configured to magnetically capture tagged cells.

Abstract: Photovoltaic cells are fabricated in which the compositions of the light-absorbing layer and the electron-accepting layer are selected such that at least one side of the junction between these two layers is substantially depleted of charge carriers, i.e., both free electrons and free holes, in the absence of solar illumination. In further aspects of the invention, the light-absorbing layer is comprised of dual-shell passivated quantum dots, each having a quantum dot core with surface anions, an inner shell containing cations to passivate the core surface anions, and an outer shell to passivate the inner shell anions and anions on the core surface.

Abstract: Photovoltaic cells are fabricated in which the compositions of the light-absorbing layer and the electron-accepting layer are selected such that at least one side of the junction between these two layers is substantially depleted of charge carriers, i.e., both free electrons and free holes, in the absence of solar illumination. In further aspects of the invention, the light-absorbing layer is comprised of dual-shell passivated quantum dots, each having a quantum dot core with surface anions, an inner shell containing cations to passivate the core surface anions, and an outer shell to passivate the inner shell anions and anions on the core surface.

Abstract: Photovoltaic cells are fabricated in which the compositions of the light-absorbing layer and the electron-accepting layer are selected such that at least one side of the junction between these two layers is substantially depleted of charge carriers, i.e., both free electrons and free holes, in the absence of solar illumination. In further aspects of the invention, the light-absorbing layer is comprised of dual-shell passivated quantum dots, each having a quantum dot core with surface anions, an inner shell containing cations to passivate the core surface anions, and an outer shell to passivate the inner shell anions and anions on the core surface.

Abstract: Contemplated methods and devices comprise performing electrochemical sample analysis in a multiplexed electrochemical detector having reduced electrical cross-talk. The electrochemical detector includes electrodes that share a common lead from a plurality of leads. The sample, which may be a liquid sample, is introduced into one or more sample wells and a signal is applied to at least one of the electrodes. A response signal is measured while simultaneously applying a substantially fixed potential to each of a remainder of the plurality of leads.

Abstract: This application describes photovoltaic devices that include, in some embodiments, plasmonic nanoparticles and colloidal quantum dots and that have enhanced photovoltaic conversion efficiencies. This application also describes methods of making and using photovoltaic devices. Certain photovoltaic devices include plasmonic nanoparticles integrated with light absorbing semiconductor nanoparticles such as, but not limited to, colloidal quantum dots. Certain photovoltaic devices include solution-processed materials (e.g., colloidal plasmonic and light absorbing semiconductor nanoparticles) that are specifically tuned to enhance overall photovoltaic performance through increased absorbance of the light absorbing material.

Abstract: A recombination layer with a gradient work function is provided which increases the power-conversion efficiency of multijunction photovoltaic devices by reducing the energy barrier to charge carriers migrating between pairs of photovoltaic junctions thereby facilitating the optimal recombination of opposing electron and hole currents generated when the photovoltaic is illuminated.