Fernando Uribe Romo

Abstract

UCF researchers have developed a low-cost method for processing two-dimensional (2-D) covalent organic frameworks (COFs) that can safely be used as electrolytes in solid-state, rechargeable lithium-ion (Li-ion) batteries. The new method offers a better alternative to producing liquid electrolyte-based Li-ion batteries (that can combust upon battery failure) and to ceramic materials that require costly production methods.

Technical Details

With the new method, 2-D COF powders are impregnated with lithium salts and then mechanically pressed along a uniaxial direction into shaped objects, such as pellets. The result produces materials that are crystallographically aligned with a high degree of anisotropic ordering, enabling fast Li-ion conductivity and dynamics within the COFs and exceptional electrochemical stability to lithium. The method can be applied to different COFs with diverse functionalities (for example, boronate, boroxine,  ß-ketoenamine and triazine) and different symmetries (such as hexagonal, trigonal, tetragonal or monoclinic symmetry).

Benefit

Market Application

Publications

Mechanically Shaped Two-Dimensional Covalent Organic Frameworks Reveal Crystallographic Alignment and Fast Li-Ion Conductivity,  Journal of the American Chemical Society, 2016,138, 31, 9767-9770

Abstract

The University of Central Florida invention relates to methods for the development of a solid-state battery based on a new concept of a redox and ionically graded single-phase metal-organic framework (MOF).

Abstract

The University of Central Florida invention comprises compositions and methods that use sustainable materials to produce white light with highly tunable temperature and high efficiency. Most of the light consumption in the United States (almost 280 billion kWh of energy yearly) is in the form of white light obtained from a variety of devices. This includes light-emitting diodes (LEDs), compact fluorescent lamps (CFLs) and incandescent bulbs. Each of these devices has a unique light-producing mechanism that provides advantages and disadvantages. For example, while LEDs are the most energy-efficient, they are known for providing monotone lighting. Also, obtaining white light from LEDs requires expensive and rare elements such as iridium, gallium, and lanthanides, whose production and use are not environmentally friendly. In another example, incandescent lighting devices deliver comfortable color and warmth but are far less energy efficient.

To overcome such challenges, UCF researchers developed multivariate metal-organic frameworks (MTV MOFs) that produce white light with emission temperatures that range from cool to warm. A framework can be systematically adjusted solely by the ratio of red, green, blue, and orange emitting linkers. Among their properties, the MOFs can facilitate storage, separation, transport, and chemical transformation of chemical guests by accommodating the guest molecules, such as gases, ions, water, and cognizable organic molecules, in well-defined pores.

Technical Details

The UCF invention consists of techniques for designing and synthesizing materials that, among other functions, emit light and allow for fine-tuning of the light emission profile. The invention employs MTV MOFs, a class of materials whose primary building units are a mix of organic linkers and varied functional groups with a mix of metal ions.

The MTV MOF may include at least one light-emitting linker in an amount sufficient for the composition to produce broadband emission spectra in high quantum yields. By varying the ratios of light-emitting linkers in an MTV MOF, the photophysical properties of the materials can be easily adjusted, resulting in behavior that can be customized for specific applications. For example, the linker type enables the assembly of porous crystalline MOF materials, several kinds of mixed-linker MOFs, including pillared-layer mixed-linker MOFs, cage-directed mixed-linker MOFs, cluster-based mixed-linker MOFs, and structure templated mixed-linker MOFs. In many embodiments, the temperature of the emitted white light is adjusted simply by adjusting the orange:blue linker ratio.

Partnering Opportunity

The research team is seeking partners for licensing/research collaboration.

Benefit

Market Application

Publications

Solid State Multicolor Emission in Substitutional Solid Solutions of Metal-Organic Frameworks, Journal of the American Chemical Society 2019 141 (28), 11298-11303, DOI: 10.1021/jacs.9b05191.

Abstract

Researchers at the University of Central Florida have developed a simple, low-cost way to fight global warming and produce new, storable energy. The breakthrough technology provides a titanium-based metal organic framework (MOF) that reacts with visible (blue) light to photocatalytically reduce carbon dioxide (CO2) into two solar fuels: formate and formamide derivatives.

The  CO2  in the Earth's atmosphere is a major contributor to global warming, and the amount is far too much for natural photosynthesis to reduce in the short term. Though current titanium-based MOFs can reduce  CO2  using ultraviolet (UV) light, UV light is only a small percentage of the sunlight on Earth, significantly limiting the viability of those MOFs. In comparison, the new invention is more commercially viable because it can reduce  CO2  using visible light, which is more abundant. Thus, the invention enables "artificial photosynthesis," which companies, such as power plants, can use to reduce their  CO2 emissions and produce clean, storable solar fuels.

Technical Details

The invention comprises a low-cost titanium-based MOF design and methods for fabricating and using the compound to photocatalytically reduce   CO2. The safe, non-toxic MOF is a crystalline porous material that exhibits high surface area and large pore volume. Tailored to absorb a specific color of visible light, the MOF consists of titanium oxide clusters connected through organic linkers, such as 2-amino-terephthalate. For example, the MOF's linkers can be N-alkyl groups of increasing chain length (from methyl to heptyl) and varying connectivity. When illuminated under blue light, the MOF acts as a catalyst to effectively reduce carbon dioxide into solar fuels: formate and formamide derivatives.

Benefit

Market Application

Publications

Systematic Variation of the Optical Bandgap in Titanium Based Isoreticular Metal-Organic Frameworks for Photocatalytic Reduction of CO2 under Blue Light?, Journal of Materials Chemistry A,  April 7, 2017