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Owczarczyk, Zbyslaw

Publications and source records attributed to Owczarczyk, Zbyslaw.

4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

A Novel Zwitterionic Chromatography Approach to Separate Lithium from Unconventional Resources

Lithium (Li) is a key element for clean energy technologies, and, accordingly, the global lithium demand has been increasing rapidly. Therefore, to meet the Li demand and maintain supply chain stability, it is critical to develop efficient lithium extraction technologies that allow exploitation of unconventional lithium resources, such as geothermal brines and inland brine streams. However, the recovery of Li from these resources is challenging due to low Li concentration, low ratios of Li/Na, Li/Mg, or Li/Ca, and complex feed compositions. To address this, we introduced a new Direct Lithium Extraction (DLE) process using Zwitterionic Chromatography (ZIC) to separate Li from other salts. Since salts are partitioned on ZIC under water elution, no reagent chemicals are needed, and the Li separation is not limited by the adsorption capacity. We prepared 13 different zwitterionic (ZI) resins to investigate the salt retention on various ZI groups and then screened out promising sorbents for efficient Li separation. It was found that salt retention was synergistically affected by the pore size and ZI configurations. Using carboxybetaine (QAC3CA) sorbents, multicomponent separations showed that Li can be partitioned from divalent salts or Na with selectivities of 1.8 or 1.9, respectively. Although the selectivity is relatively low, in real brine tests, Li was separated from Ca and Mg with 79.2 % yield, showing the potential for a continuous process to achieve high productivity and high yield. Simulation studies suggest the salt elution mechanism is related to the hydration reaction energy and the effective hydrated radius of cations.

critical minerals↗
DOE OSTI2019

Stability of push–pull small molecule donors for organic photovoltaics: spectroscopic degradation of acceptor endcaps on benzo[1,2- b :4,5- b ′]dithiophene cores

High efficiency organic photovoltaic devices have relied on the development of new donor and acceptor materials to optimize opto-electronic properties, promote free carrier generation, and suppress recombination losses. With single junction efficiencies exceeding 15%, materials development must now target long-term stability. This work focuses on the photobleaching dynamics and degradation chemistries of a class of small molecule donors inspired by benzodithiophene terthiophene cores (BDT-3T) with rhodanine endcaps, which have demonstrated 9% efficiency in single junction devices and >11% in ternary cells. Density functional theory was used to design three additional molecules with similar synthetic pathways and opto-electronic properties by simply changing the electron accepting endcap to benzothiazoleacetonitrile, pyrazolone, or barbituric acid functional groups. This new class of semiconductors with equivalent redox properties enables systematic investigation into photobleaching dynamics under white light illumination in air. Degradation chemistries are assessed via unique spectroscopic signatures for the BDT-3T cores and the endcaps using photoelectron spectroscopies. We show that the pyrazolone undergoes significant degradation due to ring opening, resulting in complete bleaching of the chromophore. The barbituric and rhodanine endcap molecules have moderate stability, while the benzothiazoleacetonitrile group produces the most stable chromophore despite undergoing some oxidative degradation. Collectively, our results suggest the following: (i) degradation is not just dependent on redox properties; (ii) core group stability is not independent of the endcap choice; and (iii) future design of high efficiency materials must consider both photo and chemical stability of the molecule as a whole, not just individual donor or acceptor building blocks.

14 SOLAR ENERGY↗
DOE OSTI2019

The impact of alkyl tri-methyl ammonium side chains on perfluorinated ionic membranes for electrochemical applications

Three different perfluorinated type polymers as anion exchange membranes for electrochemical applications were studied. They have a sulfonamide linkage to a spacer methylene chain attached to a tri-methyl ammonium cation, specifically using a three carbon spacer chain (PFAEM_H_C3), and methylated imide polymers with three (PFAEM_CH3_C3) and six carbon spacer chain (PFAEM_CH3_C6). There are significant number of zwitterionic side chains in the PFAEM_H_C3 polymer and very few in the PFAEM_CH3_C3 or the PFAEM_CH3_C6 polymer. They have similar halide conductivity, but the PFAEM_CH3_C6 showed highest OH - conductivity, 122 mS cm -1 at 80 degrees C and 95% RH. The larger spacer chain polymer, PFAEM_CH3_C6 has a higher water uptake value (..lambda..= 9) compared to PFAEM_CH3_C3(λ=°7) at 60 degrees C and 95% RH in the Cl - form. Therefore, it has a larger domain spacing of 4.9 nm versus 4.1 nm from small angle X-ray scattering data. The polymer was characterized by FTIR and DFT was used to fully assign the spectra.

36 MATERIALS SCIENCE↗