Abstract: The present disclosure relates to a composition that includes a perovskite of A2BX4, where A includes an R-form of a chiral molecule of at least one of and/or an S-form of the chiral molecule, B includes a cation, X includes an anion, R1 includes a first carbon chain having between 2 and 5 carbon atoms, R2 includes at least one of a hydrogen atom, a halogen atom, a carboxylic acid group, an alkoxy group, and/or a second carbon chain, and R3 includes a third carbon chain.

Abstract: Techniques for fabrication of kesterite Cu—Zn—Sn—(Se,S) films and improved photovoltaic devices based on these films are provided. In one aspect, a method of fabricating a kesterite film having a formula Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; and ?1?q?1 is provided. The method includes the following steps. A substrate is provided. A bulk precursor layer is formed on the substrate, the bulk precursor layer comprising Cu, Zn, Sn and at least one of S and Se. A capping layer is formed on the bulk precursor layer, the capping layer comprising at least one of Sn, S and Se. The bulk precursor layer and the capping layer are annealed under conditions sufficient to produce the kesterite film having values of x, y, z and q for any given part of the film that deviate from average values of x, y, z and q throughout the film by less than 20 percent.

Abstract: Techniques for fabrication of kesterite Cu—Zn—Sn—(Se,S) films and improved photovoltaic devices based on these films are provided. In one aspect, a method of fabricating a kesterite film having a formula Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; and ?1?q?1 is provided. The method includes the following steps. A substrate is provided. A bulk precursor layer is formed on the substrate, the bulk precursor layer comprising Cu, Zn, Sn and at least one of S and Se. A capping layer is formed on the bulk precursor layer, the capping layer comprising at least one of Sn, S and Se. The bulk precursor layer and the capping layer are annealed under conditions sufficient to produce the kesterite film having values of x, y, z and q for any given part of the film that deviate from average values of x, y, z and q throughout the film by less than 20 percent.

Abstract: Techniques for fabrication of kesterite Cu—Zn—Sn—(Se,S) films and improved photovoltaic devices based on these films are provided. In one aspect, a method of fabricating a kesterite film having a formula Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; and ?1?q?1 is provided. The method includes the following steps. A substrate is provided. A bulk precursor layer is formed on the substrate, the bulk precursor layer comprising Cu, Zn, Sn and at least one of S and Se. A capping layer is formed on the bulk precursor layer, the capping layer comprising at least one of Sn, S and Se. The bulk precursor layer and the capping layer are annealed under conditions sufficient to produce the kesterite film having values of x, y, z and q for any given part of the film that deviate from average values of x, y, z and q throughout the film by less than 20 percent.

Abstract: Low-temperature sulfurization/selenization heat treatment processes for photovoltaic devices are provided. In one aspect, a method for fabricating a photovoltaic device is provided. The method includes the following steps. A substrate is provided that is either (i) formed from an electrically conductive material or (ii) coated with at least one layer of a conductive material. A chalcogenide absorber layer is formed on the substrate. A buffer layer is formed on the absorber layer. A transparent front contact is formed on the buffer layer. The device is contacted with a chalcogen-containing vapor having a sulfur and/or selenium compound under conditions sufficient to improve device performance by filling chalcogen vacancies within the absorber layer or the buffer layer or by passivating one or more of grain boundaries in the absorber layer, an interface between the absorber layer and the buffer layer and an interface between the absorber layer and the substrate.

Abstract: Techniques for enhancing energy conversion efficiency in chalcogenide-based photovoltaic devices by improved grain structure and film morphology through addition of urea into a liquid-based precursor are provided. In one aspect, a method of forming a chalcogenide film includes the following steps. Metal chalcogenides are contacted in a liquid medium to form a solution or a dispersion, wherein the metal chalcogenides include a Cu chalcogenide, an M1 and an M2 chalcogenide, and wherein M1 and M2 each include an element selected from the group consisting of: Ag, Mn, Mg, Fe, Co, Cd, Ni, Cr, Zn, Sn, In, Ga, Al, and Ge. At least one organic additive is contacted with the metal chalcogenides in the liquid medium. The solution or the dispersion is deposited onto a substrate to form a layer. The layer is annealed at a temperature, pressure and for a duration sufficient to form the chalcogenide film.

Abstract: Techniques for enhancing energy conversion efficiency in chalcogenide-based photovoltaic devices by improved grain structure and film morphology through addition of urea into a liquid-based precursor are provided. In one aspect, a method of forming a chalcogenide film includes the following steps. Metal chalcogenides are contacted in a liquid medium to form a solution or a dispersion, wherein the metal chalcogenides include a Cu chalcogenide, an M1 and an M2 chalcogenide, and wherein M1 and M2 each include an element selected from the group consisting of: Ag, Mn, Mg, Fe, Co, Cd, Ni, Cr, Zn, Sn, In, Ga, Al, and Ge. At least one organic additive is contacted with the metal chalcogenides in the liquid medium. The solution or the dispersion is deposited onto a substrate to form a layer. The layer is annealed at a temperature, pressure and for a duration sufficient to form the chalcogenide film.

Abstract: Low-temperature sulfurization/selenization heat treatment processes for photovoltaic devices are provided. In one aspect, a method for fabricating a photovoltaic device is provided. The method includes the following steps. A substrate is provided that is either (i) formed from an electrically conductive material or (ii) coated with at least one layer of a conductive material. A chalcogenide absorber layer is formed on the substrate. A buffer layer is formed on the absorber layer. A transparent front contact is formed on the buffer layer. The device is contacted with a chalcogen-containing vapor having a sulfur and/or selenium compound under conditions sufficient to improve device performance by filling chalcogen vacancies within the absorber layer or the buffer layer or by passivating one or more of grain boundaries in the absorber layer, an interface between the absorber layer and the buffer layer and an interface between the absorber layer and the substrate.

Abstract: Techniques for fabrication of kesterite Cu—Zn—Sn—(Se,S) films and improved photovoltaic devices based on these films are provided. In one aspect, a method of fabricating a kesterite film having a formula Cu2?xZn1+ySn(S1?zSez)4+q, wherein 0?x?1; 0?y?1; 0?z?1; and ?1?q?1 is provided. The method includes the following steps. A substrate is provided. A bulk precursor layer is formed on the substrate, the bulk precursor layer comprising Cu, Zn, Sn and at least one of S and Se. A capping layer is formed on the bulk precursor layer, the capping layer comprising at least one of Sn, S and Se. The bulk precursor layer and the capping layer are annealed under conditions sufficient to produce the kesterite film having values of x, y, z and q for any given part of the film that deviate from average values of x, y, z and q throughout the film by less than 20 percent.

Abstract: Techniques for fabrication of kesterite Cu—Zn—Sn—(Se,S) films and improved photovoltaic devices based on these films are provided. In one aspect, a method of forming metal chalcogenide nanoparticles is provided. The method includes the following steps. Water, a source of Zn, a source of Cu, optionally a source of Sn and at least one of a source of S and a source of Se are contacted under conditions sufficient to produce a dispersion of the metal chalcogenide nanoparticles having a Zn chalcogenide distributed within a surface layer thereof. The metal chalcogenide nanoparticles are separated from the dispersion and can subsequently be used to form an ink for deposition of kesterite films.

Abstract: Techniques for preparing chalcogen-containing solutions using an environmentally benign borane-based reducing agent and solvents under ambient conditions, as well as application of these solutions in a liquid-based method for deposition of inorganic films having copper (Cu), zinc (Zn), tin (Sn), and at least one of sulfur (S) and selenium (Se) are provided. In one aspect, a method for preparing a chalcogen-containing solution is provided. The method includes the following steps. At least one chalcogen element, a reducing agent and a liquid medium are contacted under conditions sufficient to produce a homogenous solution. The reducing agent (i) contains both boron and hydrogen, (ii) is substantially carbon free and (iii) is substantially metal free.

Abstract: A high sensitivity, organic solvent developable, high resolution photoresist composition for use in E-beam lithography is disclosed. The composition of the present invention comprises a high sensitivity, soluble, film forming photoresist composition of dendrimeric calix [4]arene derivatives and processes for forming lithographic patterns with a crosslinker selected from glycoluril derivatives capable of reacting with these dendrimer under acid catalysis, a photoacid generator and an organic solvent. The composition of the present invention is particularly useful for production of negative tone images of high resolution (less than 100 nanometers).

Abstract: An organic-inorganic perovskite having alternating layers of an inorganic anion layer and an organic cation layer is provided. More particularly, the inorganic anion layer of the organic-inorganic perovskite has a trivalent or higher valent metal halide framework and the organic cation layer has a plurality of organic cations capable of templating the metal-deficient inorganic anion layers within the perovskite structure. Methods of preparing the organic-inorganic perovskite according to the present invention are also provided.

Abstract: The present invention relates to an electroluminescent device comprising an anode, a cathode and an emitting layer. The emitting layer comprises a self-assembling organic-inorganic hybrid material containing an organic component and an inorganic component. The organic component comprises a dye that fluoresces in the visible range. In addition, an optically inert component may replace a portion of the organic dye component to increase fluorescence.

Abstract: A thin film transistor (TFT) device structure based on an organic-inorganic hybrid semiconductor material, that exhibits a high field effect mobility, high current modulation at lower operating voltages than the current state of the art organic-inorganic hybrid TFT devices. The structure comprises a suitable substrate disposed with the following sequence of features: a set of conducting gate electrodes covered with a high dielectric constant insulator, a layer of the organic-inorganic hybrid semiconductor, sets of electrically conducting source and drain electrodes corresponding to each of the gate lines, and an optional passivation layer that can overcoat and protect the device structure. Use of high dielectric constant gate insulators exploits the gate voltage dependence of the organic-inorganic hybrid semiconductor to achieve high field effect mobility levels at very low operating voltages.

Abstract: The present invention relates to an organic-inorganic hybrid material comprising an organic component and an inorganic component. The organic component comprises a dye that fluoresces in the visible range. In addition, an optically inert component may replace a portion of the organic dye component to increase fluorescence.

Abstract: In order to form a film of organic-inorganic hybrid material, such as a perovskite material, in a selected stoichiometric ratio upon a surface of a substrate, the proposed method entails a number of simple steps. First, a substrate and a selected quantity of an organic-inorganic hybrid material are placed in a chamber, with the hybrid material being placed on a heater. Then, the hybrid material is heated sufficiently, as by passing an electric current through the heater, to cause its total ablation. As a consequence, a film of the organic-inorganic hybrid material, in the aforesaid selected stoichiometric ratio, reassembles as a film upon a surface of the substrate. During the heating step, the chamber may be either evacuated to a pressure below 10.sup.-3 torr or filled with an inert gas, such as nitrogen.

Abstract: There is disclosed herein novel organic-inorganic layered perovskites of the general formula A.sub.2 MX.sub.4 where A is an organic ammonium cation, M is a divalent rare earth metal and X is a halogen. These compounds can be made by a low temperature (about 100.degree.-160.degree. C.) solid state reaction between the organic ammonium salt with the appropriate hydrogen halide and MX.sub.2 where M is a divalent rare earth metal and X is a halogen). A specific example is (C.sub.4 H.sub.9 NH.sub.3).sub.2 EuI.sub.4 which has been made through a reaction at about 140.degree.-160 C. between C.sub.4 H.sub.9 NH.sub.2. HI and EuI.sub.2. This new compound produces intense blue photoluminescence at room temperature, with a peak wavelength of 460 nm and a fairly narrow peak width (FWHM=24 nm). In addition to the simple aliphatic ammonium cations of the form C.sub.n H.sub.2n+1 NH.sub.3.sup.+, e.g., propylammonium (C.sub.3 H.sub.7 NH.sub.3) and butylammonium (C.sub.4 H.sub.9 NH.sub.

Abstract: A convenient two-step dipping technique for preparing high-quality thin films of a variety of perovskites is provided by the invention. Thin films of Mi.sub.2 (M=Pb, Sn) were first prepared by vacuum-depositing MI.sub.2 onto ash glass or quart substrates, which were subsequently dipped into a solution containing the desired organic ammonium cation for a short period of time. Using this technique, thin films of different layered organic-inorganic perovskites (RNH.sub.3).sub.2 (CH.sub.3 NH.sub.3).sub.n-1 M.sub.n I.sub.3n+1 (R=butyl, phenethyl; M=Pb, Sn; and n=1, 2) and three-dimensional perovskites CH.sub.3 NH.sub.3 MI.sub.3 (M=Pb, Sn; i.e. n=.infin.) were successfully prepared at room temperature. The lattice constants of these dip-processed perovskites are very similar to those of the corresponding compounds prepared by solution-growth or by solid state reactions. The layered perovskite thin films possess strong photoluminescence, distributed uniformly across the film areas.