Ultra-high Purity Research Articles

Reduced Self‐Absorption of Quasi‐2D Perovskites and Their Application in Color Conversion Layers

AbstractLead halide perovskites (LHPs) have recently demonstrated great potential for color conversion layers (CCLs) in backlight displays due to their ultrahigh color purity and high photoluminescence quantum yield. However, the severe self‐absorption effect of LHPs due to small Stokes shift restricts their optical conversion efficiency (OCE) as CCLs. Herein, quasi‐2D perovskites are exploited and the ultrafast energy transfer mechanism is introduced. Using this approach, CCLs Stokes shift is increased and its self‐absorption coefficient is reduced by nearly threefold (from 6.2 × 104 to 2.1 × 104 cm−1). Therefore, color conversion light‐emitting diodes based on quasi‐2D perovskites are demonstrated with an improved OCE of 30% and ideal working stability of 1% loss under blue light irradiation of 35 mW cm−2 indicating their great potential for application in backlight display.

Machine-learning-assisted multi-objective optimization in vertical zone refining of ultra-high purity indium

Optimization of processing parameters cannot rely on the trial-and-error method for the production of ultra-high purity metals owing to the complexity of indium raw material and multi-pass processing procedure. A multi-objective optimization strategy was proposed to optimize the process parameters for vertical zone refining of 7N-grade ultra-high purity indium (In) by using machine learning (ML). Firstly, classification models were established for certain impurities (Si, S, Fe, Zn, Ni, Cu and As). In these models, the Synthetic Minority Over-sampling Technique (SMOTE) was introduced to overcome the sample imbalance problem of the experimental dataset. The accuracy of these classification models reached above 0.9. Secondly, a ridge regression model was built to predict the total impurity content in the product. The root mean square error (RMSE) was 0.023, the Pearson correlation coefficient (r) was 0.91, and R-squared (R2) value was 0.79. Using these models, high-throughput virtual screening was performed to conduct vertical zone-refining experiments, which in turn validated the reliability of the models. Feature analysis by Shapley additive explanations (SHAP) revealed that the total impurity content in the final product strongly depended on the content of Ni and Sn impurities in the 6N-grade indium raw material and on the velocity parameter of the 2rd through 4th zone passes (V2). A lower V2 is favorable for eliminating impurities from indium raw material with total impurity content ranging from 0.2 ppm to 0.4 ppm.

Status of the SABRE South experiment at the Stawell underground physics laboratory

The SABRE (Sodium iodide with Active Background REjection) experiments aim to detect an annual rate modulation from dark matter interactions in ultra-high purity NaI(Tl) crystals. The SABRE South experiment is located at the Stawell Underground Physics Laboratory (SUPL), Australia, and is the first deep underground laboratory in the Southern Hemisphere. SABRE South is designed to disentangle seasonal or site-related effects from the dark matter-like modulated signal first observed by DAMA/LIBRA in the Northern Hemisphere using an active veto and muon detection system. It is a partner to the SABRE North effort at the Laboratori Nazionali del Gran Sasso (LNGS). SABRE South is instrumented with ultra-high purity NaI(Tl) crystals immersed in a linear alkyl benzene (LAB) based liquid scintillator veto, further surrounded by passive steel and polyethylene shielding and a plastic scintillator muon veto. Significant work has been undertaken to understand the experimental backgrounds and performance of the crystals. The SABRE South experiment is under construction, and will be commissioned from late 2022 to early 2023. We will present the final design of SABRE South, the status of its construction, its expected background, and its sensitivity to a DAMA/LIBRA like modulation. We will also present recent quenching factor measurements of sodium nuclear recoils in NaI(Tl) crystals measured at the Heavy Ion Accelerator Facility, and a report on the status of SUPL.

Color-tunable donor-acceptor-type B-embedded dioxygen-bridged π-conjugated molecules: Synthesis, structures, and optical properties

Three novel donor-acceptor-type B-embedded dioxygen-bridged π-conjugated molecules (BO-CZ, BO-N and BO-NO) featuring different electron donors have been synthesized by Suzuki-Miyaura C–C coupling. Single crystal structures show that both BO-CZ and BO-N exhibit obvious π-π interactions in solid state due to the good planarity of the B-embedded dioxygen-bridged π-conjugated unit. More importantly, by controlling different electron donor units, the luminescence color of these compounds can be changed from deep blue to yellow with high luminescence quantum efficiency, up to close to 100%. Notably, the deep-blue-emitting molecule BO-CZ in film exhibits an ultrahigh color purity with a very narrow full width at half maximum (FWHM = 36 nm) and CIE coordinates (0.164, 0.019). Interestingly, these donor-acceptor-type boron-containing molecules with Lewis acidity can interact with Lewis bases (pyridine and DMAP) and induce interesting optical changes.

Design and operation of the PandaX-4T high speed ultra-high purity xenon recuperation system

In order to recuperate the ultra-high purity xenon from PandaX-4T dark matter detector to high-pressure gas cylinders in emergency or at the end-of-run situation, a high speed ultra-high purity xenon recuperation system is designed and developed. This system includes a diaphragm pump, the heat management system, the main recuperation pipeline, the reflux pipeline, the auxiliary recuperation pipeline and the automatic control system. The liquid xenon in the detector is vaporized by the heat management system, and the gaseous xenon is compressed to 6 MPa at the flow rate of 200 standard litres per minute (SLPM) using the diaphragm compressor. The high-pressure xenon is filled into 128 gas cylinders via the main recuperation pipeline. During the recuperation, the low pressure and temperature conditions of 2 ∼ 3 atmospheres and 178 ∼ 186.5 K in PandaX-4T dark matter detector are kept by the cooperation of the main recuperation pipeline, reflux pipeline and the auxiliary recuperation pipeline to guarantee the safety, and the purity of the recuperated xenon gas is measured to ensure no contamination happened. The development of the high speed ultra-high purity xenon recuperation system is important for the operation of large-scale dark matter detectors with the requirements of strict temperature and pressure environment and low background.

The role of Cr concentration and temperature on cavity swelling with co-injected helium in dual-ion irradiated Fe and Fe-Cr alloys

The level of chromium plays an essential role in irradiation tolerance of Fe-Cr ferritic alloys. However, conflicting results have been reported regarding the dependence of cavity swelling under irradiation on Cr level and temperature. Here, we have performed a comprehensive set of simultaneous dual-ion (Ni + He) irradiations to high dose (∼30 displacements per atom, dpa) at 400–550 °C on a series of ultra-high purity Fe and Fe-Cr binary alloys (3–14 wt.%Cr). Helium co-implantation rates of 0.1 and 10 appm He/dpa were selected to examine He synergistic effects relevant for fission and fusion reactor conditions, respectively. Cavities were observed in all irradiated samples by transmission electron microscopy. The results show that higher He implantation rate causes a shift in the swelling peak to higher temperatures in both Fe and Fe-Cr alloys. When assuming smaller cavities as biased sinks, the non-monotonic nature of the cavity swelling behavior is related to the ratio of biased to unbiased point defect sink strengths. Cr-enriched precipitates were observed in Fe-14Cr irradiated at 400 °C by atom probe tomography. Our analysis suggests the formation of Cr-enriched precipitates could suppress cavity swelling for Fe-Cr alloys with Cr content above 10 wt%.

Effect of mechanical alloying of Ti and B in pre alloyed gas atomized powder on carbide dispersed austenitic matrix of Iron based hardfacing alloy

In fast breeder reactors Austenitic Stainless steel structural components like grid plates, sleeves, etc. are in contact under stress in a flowing liquid sodium environment at temperatures up to 823 K. To tackle self-welding characteristics, hardfacing alloys are required. In the present work, Thermocalc software was used to arrive at suitable composition of alloy consisting of Fe-20Cr-2C-18Ni-2Mn-4Si-2Ti-1B. This proposed alloy was atomized in argon atmosphere. Due to loss of Ti and B in atomization, additional alloying in the form of pure elements and ferro alloys were made by mechanical alloying in attritor ball milling setup with BPR of 10:1 (by wt.) in ultra-high purity (UHP) argon atmosphere. Mechanical alloyed powder exhibits sphericity of 0.908, apparent density of 4.3 g/cc and flow rate of 17 s per 50 g of powder. Laser cladding of 1-3 mm thick overlay layer was made on 10 mm thick SS 316 plate and its characterization was made by optical microscopy, SEM, XRD and micro-hardness. Weld overlay showed moderate distribution of complex carbides in the austenitic matrix and resultant improved hardness in the range of 445–474 HV by mechanical alloying as compared to prealloyed atomized powder.

Ultrahigh purity beta gallium oxide microstructures

Ultrahigh purity gallium oxide (Ga 2 O 3 ) microstructures were synthesized via hydrothermal method using gallium nitrate hydrate and ammonium hydroxide to synthesize gallium hydroxide, followed by calcination at a 1000 °C. Scanning electron microscopy revealed that following calcination, the material showed a large number of microparticles with lengths of ≤1 μm and diameters of 250–350 nm. Energy-dispersive X-ray spectroscopy, X-ray diffraction, Raman spectroscopy, infrared spectroscopy, and X-ray photoelectron spectroscopy analyses indicated the high purity and near-stoichiometric composition of the material. The results also confirm the formation of β-phase Ga 2 O 3 with high crystallinity.

Ultramicroporous material based parallel and extended paraffin nano-trap for benchmark olefin purification

Selective paraffin capture from olefin/paraffin mixtures could afford high-purity olefins directly, but suffers from the issues of low separation selectivity and olefin productivity. Herein, we report an ultramicroporous material (PCP-IPA) with parallel-aligned linearly extending isophthalic acid units along the one-dimensional channel, realizing the efficient production of ultra-high purity C2H4 and C3H6 (99.99%). The periodically expanded and parallel-aligned aromatic-based units served as a paraffin nano-trap to contact with the exposed hydrogen atoms of both C2H6 and C3H8, as demonstrated by the simulation studies. PCP-IPA exhibits record separation selectivity of 2.48 and separation potential of 1.20 mol/L for C3H8/C3H6 (50/50) mixture, meanwhile the excellent C2H6/C2H4 mixture separation performance. Ultra-high purity C3H6 (99.99%) and C2H4 (99.99%) can be directly obtained through fixed-bed column from C3H8/C3H6 and C2H6/C2H4 mixtures, respectively. The record C3H6 productivity is up to 15.23 L/kg from the equimolar of C3H8/C3H6, which is 3.85 times of the previous benchmark material, demonstrating its great potential for those important industrial separations.

Gold recovery at ultra-high purity from electronic waste using selective polymeric film

We propose a sustainable Au recovery technology from e-waste with high purity and probe recyclability, which is established on a selective coordination-based colorimetric probe immobilized on the surface of a quartz substrate to form a thin polymeric film (F1). In particular, the N,N'-dimethylacrylamide (DMA), (E)-2-(methyl(4-(phenyldiazenyl)phenyl)amino)ethyl acrylate (M1), and N-(4-benzoylphenyl)acrylamide (BPAm) are copolymerized by free radical copolymerization to yield the polymeric probe [p(DMA-co-M1-co-BPAm)] (designated as P1). M1 contains a selective 1:1 Au binding site. P1 exhibited sensitive and selective colorimetric responses toward Au(III) in aqueous media with naked-eye detectability via a color change from yellow to brick-red. The immobilized film, F1, was able to determine the presence of Au(III) in various e-waste samples via the color changes, which is in turn used to decide if further Au recovery is lucrative. Thereafter, trace amounts of Au at ultra-high purity (23.97 K) with Au(III) extraction capacity up to 0.40 g Au(III)/g F1 are rapidly recovered (10 min) even in the presence of an approximately 100-fold excess of other metal ions (copper and nickel) commonly found in e-waste without the use of harsh acids, bases, or toxic methods. Au(III)-liberated F1 can be used to further recover Au(III), and this process was repeated for multiple cycles.

Ensemble process for producing high-purity H2 via simultaneous in situ H2 extraction and CO2 capture

To produce fuel-cell-grade hydrogen (H 2 ) via fossil fuel reforming processes, an efficient H 2 purification method with a carbon capture unit is necessary. In this study, a sorption-enhanced water-gas shift membrane reactor (SE-WGS-MR) system combining a state-of-the-art MgO-based catalyst, carbon dioxide sorbent, and Pd/Ta membrane is developed to simultaneously capture carbon dioxide and purify H 2 . With the optimal sorption-enhanced configuration (SE-WGS), the carbon monoxide conversion is significantly enhanced to 86.6%, compared with 68.5% using the commercial catalyst only. Coupling of the Pd/Ta membrane with the WGS catalyst (WGS-MR) enable over 95% H 2 recovery, with the production of high-purity H 2 . Eventually, the ensemble of the three processes (SE-WGS-MR) afford 99.99% of carbon monoxide conversion and the extraction of high-purity H 2 with 99.5% recovery. This study demonstrates the potential of the single process integrating the catalytic reaction, adsorptive separation, and membrane purification for the production of H 2 with ultra-high purity and recovery. • Integration of WGS catalyst and CO 2 sorbent with a Pd/Ta membrane is examined • Coupling of the Pd/Ta membrane with the WGS catalyst enables over 95% H 2 recovery • Simultaneous CO 2 capture and H 2 purification shifts the CO conversion to 99.99% • The ensemble of the processes extracts ultra-pure H 2 with over 99.5% recovery Jin et al. propose an effective ensemble process for producing pure H 2 via simultaneous in situ H 2 extraction and CO 2 capture. Integration of MgO-based catalyst and CO 2 sorbent with a Pd/Ta composite membrane shifts the CO conversion to 99.99%, enabling the extraction of pure H 2 with over 99.5% recovery.

Emerald-based polyaniline-modified polyacrylonitrile nanofiber mats based solid-phase extraction for efficient and simple detection of Sudan dyes in poultry feed

Emerald-based polyaniline-modified polyacrylonitrile nanofiber mats (emerald-based PANI-PAN NFMs) were prepared and their performance as solid-phase extraction (SPE) adsorbent for extracting four Sudan dyes (Sudan I–IV) from poultry feed was evaluated. After solvent extraction, the poultry feed samples extraction solution was directly used for SPE by diluted with ultra-high purity water without any other treatment. No washing step was needed before elution, and the eluent was directly detected by the high-performance liquid chromatography-diode array detector (HPLC-DAD) without conventional concentration and filtration. The results showed that emerald-based PANI-PAN NFMs could effectively adsorb Sudan dyes through π-π conjugation and hydrogen bond. The amount of adsorbent and eluent required for the entire SPE process was only 10 mg and 600 µL, respectively. Furthermore, the emerald-based PANI-PAN NFMs were easy to regenerate, and no performance degradation was found after at least 6 times reuses. The detection limits of Sudan I–IV were 6–15 μg·kg−1 and the recoveries were 88.48 % –101.88 % with relative standard deviations (RSDs) less than 15 %, indicating the method has good sensitivity, accuracy, and precision. Compared with existing methods, the proposed method has simpler processes with practical application potential.

Cascaded Raman fiber lasers with ultrahigh spectral purity.

Random distributed feedback (RDFB) cascaded Raman fiber lasers (CRFLs) are simple, wavelength agile, and enable high-power fiber lasers outside emission bandwidths of rare-earth doped fiber lasers. However, the spectral purity, defined as the percentage of total output power in the desired Stokes wavelength band, and relative intensity noise (RIN) of these systems are limited due to the intensity noise of the pump source used for Raman conversion. RIN gets amplified and transferred to Raman Stokes orders which causes incomplete Raman conversion and hence limits the spectral purity. Here, we demonstrate a low-intensity noise (<-100 dBc/Hz from 9 kHz to 10 GHz) CRFL with a record spectral purity of ∼99%, tunable over six Stokes orders, using a very low-intensity noise, narrow linewidth Yb-fiber amplifier as a pump source.

Effective adsorption of Ultra-dilute CO2 over Polyethyleneimine-based adsorbent for H2 purification

Ultrahigh-purity hydrogen (6 N grade) suitable for hydrogen fuel cells requires the removal of CO2 impurity from commercial hydrogen feed. In this study, CO2 adsorption over a series of potential solid adsorbents was assessed at both high (0.1–1 bar) and low (hundreds of part-per-million) concentrations. With a distinct trend at higher concentrations (0.1–1 bar), PEI/S showed a remarkable CO2 capacity of 0.86 mmol/g at concentration as low as hundred part-per-million and outperformed the other adsorbents. The impacts of polyethylenimine (PEI) loading, adsorption temperature, co-existing H2O, and regenerability were investigated systematically. Adsorption isotherms of PEI/S at various loadings were represented with the Langmuir–Freundlich model, while adsorption kinetics were simulated and fitted with the AFO model. The effectiveness of PEI/S for CO2 removal was further investigated in dynamic fixed-bed breakthrough experiments. The co-presence of trace water vapor in the feed stream showed negligible inhibition on CO2 adsorption. In addition, multiple cycles of adsorption–desorption tests demonstrated the excellent regenerability of the PEI/S adsorbents. This study gave a comprehensive evaluation and demonstration of supported polyethylenimine as a potential TSA adsorbent for adsorptive removal of trace CO2 for ultrahigh purity H2 production.

(Digital Presentation) Develop a Novel Approach to Graphite Recycling in Industrial Level

Due to their high specific energy density (Wh/kg), high volumetric energy density (Wh/L) and long cycle life, lithium-ion batteries (LIBs) are being widely used in U.S. military and civilian applications. With the rapid growth of demands these years, recycling methods are developed to solve the shortages of supply for rare metal cathode materials, especially Li and Co. However, not being evaluated as high value material, graphite in spent LIBs always gets neglected. Therefore, graphite is burnt or downcycled and consequently generate CO2 gas as an inescapable result. Recent reports show the market demand for energy storage from Li-ion batteries will reach to 400 GWh in 2022, which required nearly 3 million tons of graphite, also it is estimated that 3 billion batteries are thrown away each year by Americans. Considering the raw material making graphite is organic materials from nature with an irreversible process, a vicious circle can’t be broken if graphite doesn’t get recycled. Remarkably, our group has developed a novel closed-loop hydrometallurgical process for recycling end-of-life Li-ion batteries. After developing methods of acid leaching and alkaline sintering, recycled graphite with an ultra-high purity (over 99.9%) is obtained for the first time. Being successfully scaled up to industrial level, it’s proved to be a green and high-efficient method in battery recycling. Further coating and surface treatment means are followed, recovering the capacity and improving the stability of recycled graphite to commercial standard. In summary, our research provides a novel maneuver to fully purify and recover the recycled graphite, which has great potential to be commercialized.

Direct Recycling of Cathode Active Materials from EV Li-Ion Batteries

Direct recycling of Li-ion batteries is a promising and low-cost recycling technology since the process recovers values of active materials directly without converting active materials into metal elements. However, the process is challenging from a separation perspective due to purity requirement. Herein, a new physical separation system was developed to recycle and produce ultra-high purity of cathode active materials from EV Li-ion batteries. Results showed that the recycled cathode active material product contained 99% purity of active materials with less than 500 ppm of aluminum and copper. Both the stoichimetry and structure of the recycled cathode active materials remained the same compared with those collected manually from electrode sheets. Results obtained from electrochemical testing showed that the capacity of the recycled materials was comparable to that of pristine cathode active materials, despite there was a lithium loss associated with battery charging and discharging. The present result demonstrates a viable direct recycling process for electric vehicle Li-ion batteries.

Challenges and Opportunities for the Blue Perovskite Quantum Dot Light-Emitting Diodes

Perovskite quantum dots (PQDs), as the promising materials for the blue light-emitting diodes (LEDs), own huge advantages as ultra-high color purity, flexibility and whole-spectrum tunability. Through dimensional and compositional engineering, PQD-LEDs have shown superiority in deep-blue light emission. However, compared with the fast development of red and green PeLEDs, the electroluminescent performance of PQD-LEDs has faced more obstacles. In this review, we aim to explore and state the uniqueness and the possible solutions for the bottleneck problems of the PQD-LEDs.

Abstract 3802: Micromilieu-dependent transcriptional memory of tumor vessel endothelial cells in colorectal cancer

Abstract Purpose of the study: Tumor microenvironment (TME)-induced plasticity of fibroblasts and immune cells are known to contribute to cancer pathogenesis. In contrast, only little is known about the existence, stability, functions and prognostic potential of different plastic phenotypes of tumor vessel endothelial cells (TECs) in cancer. Recently, transcriptional memory effects have been observed in different cell lines after cytokine stimulation in vitro. From this we developed the hypothesis that isolated TEC may exhibit TME-dependent transcriptional memories, which may provide novel insights into the intratumoral effects on TEC plasticity in cancer. To investigate this, we isolated ultrapure TECs from colorectal cancer (CRC) with prognostically favorable (Th-1-like) or worse (non-Th1-like) immune-micro-environments and analyzed the prescence of TME-associated transcriptional memory patterns. Methods: TECs and as controls normal colon endothelial cells (NECs), PBMCs and tumor cells (isolated by laser-microdissection) from the same CRC patients (n=75) were isolated by FACS-sorting. Ultra high purity (98%) of TECs and NECs was validated by qPCR and immunocytochemistry. Quality validated complete sample sets from 12 patients (Th-1-like, n=6, non-Th1-like, n=6) were compared using exome sequencing, Clariome S chips and EPICmethylation. Integrative bioinformatics was used to identify differential gene sets and to predict their association with prognosis. Results: Differential transcriptional memory patterns were detected in TECs derived from CRC with different prognostic TMEs. Of note, the aggressiveness of the originating tumors was reflected by the functions of the vascular transcriptional memory genes. The transcriptional memory was imprinted by epigenetic DNA methylation and not due to acquired somatic variants in the genome. These results could be successfully confirmed by alternative methods. Most importantly, integrative bioinformatics analyses retrieved seven vascular memory genes (VMG), which were expressed in the TECs in a TME-dependent manner and predicted the outcome of patients in an independent cohort of CRC patients. Conclusion: Our findings demonstrate for the first time a TME-dependent transcriptional memory of TECs, providing a clinically relevant indicator of intra-tumoral TME-dependent vascular plasticity with perspectives for patient stratification in vessel-directed tumor therapies. Citation Format: Michael Stürzl, Maximilian Fuchs, Meik Kunz, Nicholas Dickel, Bernt Popp, Steffen Uebe, Arif B. Ekici, Carol I. Geppert, Susanne Merkel, Vera S. Schellerer, Elisabeth Naschberger. Micromilieu-dependent transcriptional memory of tumor vessel endothelial cells in colorectal cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3802.

Optimal Polarization-Entanglement Source: Frequency-Converted SPDC with Degeneracy, Indistinguishability, and Ultrahigh Purity That is Configurable Over a Large Spectral Range

Modeling and simulations of entanglement-based quantum-networking protocols commonly assume perfect entangled states. Some investigations have been performed, which show how imperfections cause the efficiency of the protocols to rapidly deteriorate. For polarization-entangled states created by spontaneous-parametric down-conversion (SPDC), the fundamentals of phase matching lead to a trade-off problem for the optimal properties of the state. We present a SPDC method, which circumvents the trade-off problem and allows one to obtain degeneracy, indistinguishability, and heralded-single-photon spectral purity greater than $99\mathrm{%}$ for any target SPDC wavelength in the visible and near-infrared spectrum. Therefore, our method can, in principle, generate polarization-entangled states that are optimal for polarization-entanglement-based quantum-networking protocols.

Covalent organic frameworks as crystalline sponges for enzyme extraction and production from natural biosystems

Biomacromolecules, as represented by enzymes have played critical parts in various fields, especially in biomanufacture and biomedicinal applications. However, their purification from complex biological systems is of great significance but very challenging. Herein, we develop an approach using high-performance covalent organic frameworks (COFs) as crystalline sponges to extract and produce enzymes directly from the complex natural biosystem. For instance, lysozyme with high purity and activity is successfully extracted from chicken egg white through a simple adsorption and elution process. Attributed to the well-tuned pore microenvironment of COFs, both high uptake and selectivity can be realized by this high-performance crystalline sponges. Notably, the encapsulated lysozyme can be smartly and conveniently released by pH adjustment of the eluent. The harvested lysozyme demonstrates ultrahigh purity and improved activity, surpassing the commercial lysozyme (activity boosted up to 344%). The mild operation condition and good protection effect of COFs contribute to the high activity of the obtained enzyme. Moreover, compared with conventional separation media, COFs sponges demonstrate superior selectivity, efficiency, and reusability. One gram of COFs can produce ∼ 0.69 g of enzyme product per batch, and the COFs can be reused for at least 5 times. This study opens up a new avenue to extract enzymes and provides valuable guidance for the design of crystalline sponges for highly efficient bioseperation.