Article
Environmental Sciences
Diana M. Rodriguez, Natalia Mayordomo, Dieter Schild, Salim Shams Aldin Azzam, Vinzenz Brendler, Katharina Mueller, Thorsten Stumpf
Summary: The study investigated the reductive immobilization of Tc-99 using a synthetic FeS2 mixture, finding complete removal of Tc at certain pH levels and revealing the oxidation of S2- to SO42- by marcasite as a key mechanism for Tc immobilization. The research provides new insights into the redox reactions involved in Tc(VII) mobilization and highlights the potential of marcasite for natural Tc remediation by delaying re-oxidation of Tc(IV).
Article
Environmental Sciences
Sarah Bluteau, Sidney Omelon
Summary: Municipal biosolids contain organic and inorganic phosphorus that can be recovered as fertilizer by dissolving iron phosphates. Adding sodium sulfide can increase the solubility of organic orthophosphates, but it may also lead to material corrosion and reduce P recovery efficiency.
JOURNAL OF ENVIRONMENTAL MANAGEMENT
(2024)
Article
Nanoscience & Nanotechnology
Farkhod Azimov, Jinseok Lee, Subin Park, Hyun Min Jung
Summary: In order to overcome the energy density limitation of supercapacitors, a high specific capacitance material was achieved by manipulating the nanostructure of FeS2. Nanosheet-assembled FeS2 (NSA-FeS2) was fabricated using a novel method. The as-prepared NSA-FeS2 and NSA-FeS2/polyaniline (PANI) composites showed specific capacitances of 763 and 976 Fg(-1), respectively, at a current density of 0.5 Ag-1. The capacitance retention of the NSA-FeS2/PANI composites was 49% when the current density was increased to 5 Ag-1. The obtained specific capacitances demonstrated the highest values in pure FeS2 and FeS2-based composites.
ACS APPLIED MATERIALS & INTERFACES
(2023)
Article
Chemistry, Multidisciplinary
Licheng Huang, Ruiqi Yao, Zili Li, Jiaxin He, Yingqi Li, Hongxiang Zong, Shuang Han, Jianshe Lian, Yang-Guang Li, Xiangdong Ding
Summary: Transition metal-based nanomaterials have high potential as electrocatalysts for alkaline water splitting. In this study, a one-step sulfidation method was used to prepare highly efficient electrocatalysts by incorporating Mn and Zn into FeMnZn multi-metal skeletons. The optimized FMZS2 catalyst exhibited superior electrocatalytic performance for hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) compared to Pt/C and IrO2 catalysts, respectively. Furthermore, the assembled alkaline electrolyzer showed better overall water splitting capability than noble metal ones.
Article
Materials Science, Multidisciplinary
Pham Van Mao, Tatsumi Arima, Yaohiro Inagaki, Kazuya Idemitsu, Daisuke Akiyama, Takayuki Nagai, Yoshihiro Okamoto
Summary: The effect of LnO(1.5) doping on the crystal structure of U(1-y)Ln(y)O(2-x) samples was investigated, revealing a reduction in lattice parameter and the formation of higher U oxidation states. Additionally, XAFS analysis showed a decrease in U-O and Gd-O interatomic distances with increasing y.
JOURNAL OF NUCLEAR MATERIALS
(2021)
Article
Geochemistry & Geophysics
Minming Cui, George W. Luther III, Maya Gomes
Summary: This study investigates the distribution and behavior of vanadium in anoxic-sulfidic environments. The results indicate that vanadium concentrations are correlated with manganese concentrations, and the release of vanadium is mainly caused by desorption from and/or dissolution of manganese oxides. The sorption of vanadium is sensitive to pH conditions and moderately sensitive to ionic strength and phosphate concentrations. The V/Mn molar ratio can be used as a proxy to trace redox changes. The study also shows the potential of using the V/Mn record in black shales to identify changes in redox conditions in ancient oceans.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Engineering, Environmental
Zhenyu Zhao, Shuai Peng, Canming Ma, Chao Yu, Deli Wu
Summary: During the pyrite oxidation process, secondary solid iron species, including Fe-coat and Fe-dep, were found to play significant roles in hydroxyl radical generation. The redox behavior of Fe-coat and Fe-dep during pyrite oxidation affects the oxidative dissolution of pyrite and the production of hydroxyl radicals.
ENVIRONMENTAL SCIENCE & TECHNOLOGY
(2022)
Article
Environmental Sciences
Xiping Hu, Chenchen Quab, Yafeng Hana, Pan Suna, Peng Cai, Wenli Chen, Qiaoyun Huang
Summary: Heavy metal contamination of soils is a global environmental issue threatening food security and human health. Little research has been done on the impact of elevated temperatures on the migration and distribution of heavy metals in soils. This study reveals that higher temperatures increase the solubility and transformation of copper (Cu) in soils, with proteinaceous components playing a significant role in the dissolution of Cu. The findings provide a better understanding of the fate of Cu in soils and its implications for risk assessment and remediation in the context of global warming.
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
(2023)
Article
Chemistry, Multidisciplinary
Pushun Lu, Yu Xia, Yuli Huang, Zhendong Li, Yujing Wu, Xue Wang, Guochen Sun, Shaochen Shi, Zhengju Sha, Liquan Chen, Hong Li, Fan Wu
Summary: By coupling FeS2 with the superionic conductor LASI-80Si, an all-solid-state battery (ASSB) is proposed to overcome the challenges associated with rechargeable FeS2 batteries, enabling wide-temperature and large-capacity applications.
ADVANCED FUNCTIONAL MATERIALS
(2023)
Article
Environmental Sciences
Mudassir Habib, Meesam Ali, Tehreem Ayaz, Ali Shan, Guilu Zeng, Zhengyuan Zhou, Shuguang Lyu
Summary: This study aims to evaluate the TCE degradation performance through advanced oxidation process (AOP) using catalyst FeS2 in combination with oxidants persulfate (PS), peroxymonosulfate (PMS), and hydrogen peroxide (H2O2). The results found that the PMS/FeS2 system showed the highest degradation efficiency (99.84%), followed by the PS/FeS2 and H2O2/FeS2 systems. The analysis revealed that HO• and SO4• were the most effective reactive oxygen species (ROS) responsible for TCE degradation. The PMS/FeS2 system also demonstrated high stability and efficiency in the presence of surfactants and actual groundwater, making it a promising choice for TCE treatment.
ENVIRONMENTAL POLLUTION
(2023)
Article
Environmental Sciences
Meng-Wen Peng, Jing Qi, Peng Yan, Yong Guan, Ying-Ying Liu, Zhi-Hu Sun, Li-Juan Zhang, Xun Weng, Yu Shen, Fang Fang, Jin-Song Guo, You-Peng Chen
Summary: The study revealed the presence of iron-rich nanoparticles in anammoxosomes, identified as ferric oxide mineral cores. Bacterioferritin was detected by proteomics analysis, leading to the proposal of a metabolic pathway centered on iron-rich nanoparticles.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Chemistry, Multidisciplinary
Georg F. Dewald, Zainab Liaqat, Martin Alexander Lange, Wolfgang Tremel, Wolfgang G. Zeier
Summary: This study prepared FeS2 nanoparticles via a solvothermal method and evaluated their electrochemical performance in solid-state batteries, finding that smaller particle dimensions have a positive effect on FeS2 utilization. The results highlight the general importance of morphological design in realizing the promising theoretical capacity of conversion electrodes in solid-state batteries.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2021)
Article
Chemistry, Physical
Yushi Fujita, Akira Nasu, Atsushi Sakuda, Masahiro Tatsumisago, Akitoshi Hayashi
Summary: All-solid-state sodium-sulfur (Na/S) batteries are promising next-generation batteries with high safety and energy density. This study developed an all-solid-state Na/S battery with a Na2S-NaI solid solution as the active material, improving the ionic conductivity and achieving large capacity and high cycle performance.
JOURNAL OF POWER SOURCES
(2022)
Article
Electrochemistry
Shuolei Deng, Shuangsheng Xiong, Xinyi Wang, Shengmei Wang, Zhibin Zhao, Li Hou, Yang Jiang, Faming Gao
Summary: A composite material (FeS/rGO-60) consisting of spherical FeS particles distributed on the surface of graphene has been designed using CTAB-assisted synthesis. This material demonstrates excellent electrochemical properties, with ultra-high specific capacity and excellent cycling stability, surpassing previously reported FeS-based anode materials. The material also exhibits superior rate performance and stability even at higher current densities.
ELECTROCHIMICA ACTA
(2023)
Article
Materials Science, Multidisciplinary
Lei Xi, Yu Li, Dechao Zhang, Zhengbo Liu, Xijun Xu, Jun Liu
Summary: This study presents a novel method for the development of high-performance all-sulfide-based solid-state batteries by using a dissoluble sulfide electrolyte and a MOF-derived composite cathode.
ENERGY & ENVIRONMENTAL MATERIALS
(2022)
Article
Environmental Sciences
Rewati Dixit, Anirudh Gupta, Norbert Jordan, Shengqiang Zhou, Dieter Schild, Stephan Weiss, Emmanuel Guillon, Rohan Jain, Piet Lens
Summary: The study investigated the magnetic properties of biogenic elemental selenium nanospheres and nanorods obtained through the reduction of selenium(IV), showing a strong paramagnetic contribution and some ferromagnetic component mainly due to the incorporation of Fe(III).
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2021)
Article
Geochemistry & Geophysics
Nicolas Boersig, Andreas C. Scheinost, Dieter Schild, Thomas Neumann
Summary: Magnetite nanoparticles show promise as a cost-effective material for remediating polluted wastewaters, particularly in decontaminating oxyanion-forming contaminants like selenite and selenate. However, their remediation efficiency in field applications may be affected by partial oxidation and phase formation. Adsorption experiments reveal limited selenate retention and significant selenite quantities even at alkaline conditions on partially oxidized magnetite. Spectroscopic analyses detect different surface complexes of selenite, showing the potential of magnetite for immobilizing selenite without reduction processes.
APPLIED GEOCHEMISTRY
(2021)
Article
Spectroscopy
Ahmed Abdelmonem, Nikoleta Morelova, Nicolas Finck, Dieter Schild, Johannes Luetzenkirchen
Summary: This article reports unexpected behavior of sodium sulfate solutions in contact with flat surfaces based on two distinct, originally unrelated studies. The studies showed different responses of CaSO4 and Na2SO4 solutions when in contact with flat surfaces, indicating the need for further detailed studies to elucidate the phenomenon.
JOURNAL OF RAMAN SPECTROSCOPY
(2021)
Article
Chemistry, Inorganic & Nuclear
Sarah B. Duckworth, Xavier Gaona, Alexander Baumann, Kathy Dardenne, Joerg Rothe, Dieter Schild, Marcus Altmaier, Horst Geckeis
Summary: This study investigated the solubility of Tc-99(IV) under undersaturation conditions in various salt systems with different pH ranges. The results indicated that Tc exists predominantly in its +IV redox state and the presence of sulfate has minimal impact on its solubility.
Article
Chemistry, Physical
Sumit Kumar, Joerg Rothe, Nicolas Finck, Tonya Vitova, Kathy Dardenne, Aaron Beck, Dieter Schild, Horst Geckeis
Summary: The study reveals that a nanoparticulate (NpO2)-O-IV solid is the only speciation of Np sorbed on both doped and undoped magnetites. The Mn-O sites preferentially sorb Np(V) compared to Fe-O sites, indicating the significant role of impurity atom interacting with sorbing species through redox process. The participation of Mn through Fe(II)/Mn (III) redox couple in reducing sorbed Np(V) becomes significant only when the doped-magnetite contains a critical minimum concentration of Mn (>6 wt%).
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
(2022)
Article
Geochemistry & Geophysics
Mostafa Abdollahpour, Frank Heberling, Dieter Schild, Rasoul Rahnemaie
Summary: The concentrations of magnesium and calcium in natural aqueous environments are controlled by sorption and dissolution-precipitation reactions. Magnesium can bind in precipitating calcite, but at high magnesium to calcium ratios, aragonite is preferentially formed. Thermodynamic and kinetic controls may be at play at low magnesium to calcium ratios.
Article
Chemistry, Multidisciplinary
David Fellhauer, Jun-Yeop Lee, Nicole A. DiBlasi, Olaf Walter, Xavier Gaona, Dieter Schild, Marcus Altmaier
Summary: In this study, two ternary neptunium(V) hydroxides were synthesized and their crystal structures were determined. Combining structural information with solubility investigations, a comprehensive chemical and thermodynamic model of neptunium(V) behavior in NaCl-NaOH solutions was evaluated.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Chemistry, Inorganic & Nuclear
Diana M. Rodriguez, Natalia Mayordomo, Andres Parra-Puerto, Dieter Schild, Vinzenz Brendler, Thorsten Stumpf, Katharina Mueller
Summary: Researchers have studied the reduction process of Tc(VII) in noncomplex media using a combination of electrochemistry, spectroscopy, and microscopy techniques. The results provide important insights into the speciation and chemistry of Tc, and bridge the gap in fundamental knowledge.
INORGANIC CHEMISTRY
(2022)
Article
Engineering, Environmental
Qinzhiy Li, Dieter Schild, Mathieu Pasturel, Johannes Luetzenkirchen, Khalil Hanna
Summary: This study demonstrated the sensitivity of the reactivity of layered manganese oxide to dynamic anoxic/oxic conditions. Under oxic conditions, the surface-catalyzed oxidation of Mn(II) increased the removal efficiency of the target contaminant OFL. However, an increase in Mn(II)/MnO2 molar ratio suppressed MnO2 reactivity, likely due to competitive binding between Mn (II) and OFL or modification in MnO2 surface charge. Monovalent cations compensation and their effect on MnO2 particle aggregation were observed under oxic conditions. The enhancement in the removal efficiency of OFL was confirmed in the dynamic two-step anoxic/oxic process, which emulates oscillating redox conditions in environmental settings.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Article
Chemistry, Multidisciplinary
Christian Kiefer, Thomas Neill, Nese Cevirim-Papaioannou, Dieter Schild, Xavier Gaona, Tonya Vitova, Kathy Dardenne, Joerg Rothe, Marcus Altmaier, Horst Geckeis
Summary: The impact of temperature on freshly precipitated ThO2(am, hyd) solid phase was investigated using various methods. The results show that temperature significantly affects the particle size, crystallinity, and the number of hydration waters/hydroxide groups in the solid phase. Additionally, the aging time and pH also have a significant effect on the solubility of the solid phase.
FRONTIERS IN CHEMISTRY
(2022)
Article
Engineering, Environmental
Nitin Khandelwal, Nisha Singh, Ekta Tiwari, Remi Marsac, Dieter Schild, Thorsten Schaefer, Gopala Krishna Darbha
Summary: In this study, the growth behavior of redox sensitive Fe0 nanoparticles (nZVI) was found to vary on different clay surfaces. The non-swelling kaolinite (K-nZVI) showed dominant surface growth characteristics, forming larger nZVI particles (>24.8 +/- 7.4 nm) with positive zeta potential. On the other hand, the swelling bentonite (B-nZVI) exhibited negative zeta potential, mainly due to the surface charge of bentonite clay. This surface-dependent variation resulted in higher and faster removal of oxy-anions with K-nZVI, while B-nZVI showed higher sorption of cations. XPS and pXRD analysis confirmed the major removal mechanisms of reductive sorption, co-precipitation/complexation, electrostatic attraction, and complexation. The findings highlight the potential applications of K-nZVI and B-nZVI in removing specific contaminants from different types of water sources.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Materials Science, Multidisciplinary
Andres G. Munoz, T. Meyer, D. Schild, W. Calvet
Summary: The chemical transformations of native oxide on stainless steel 309 S prior to pitting in anoxic near saturated geological Q3-brine were studied using synchrotron radiation photoelectron spectroscopy (SRPES). A Cr-rich hydrated mixed iron-chromium oxide, exhibiting n-type semiconducting behavior, is formed after wet polishing. Surface accumulation of holes in the metastable pitting potential region leads to hydroxylation of oxide bonds and subsequent selective dissolution of iron. The open structure of remaining surface chromium hydroxide facilitates the inward access of chloride and water. The inhibiting effect of sulfate is attributed to the formation of stabilizing O-S-O bridges blocking chloride access.
Article
Multidisciplinary Sciences
Sanduni Ratnayake, Johannes Luetzenkirchen, Nicolas Finck, Dieter Schild, Frank Heberling, Teba Gil-Diaz, Kathy Dardenne, Joerg Rothe, Horst Geckeis
Summary: The speciation of thorium in soil samples from Sri Lanka was investigated using X-ray Absorption Spectroscopy (XAS). The results showed that thorium predominantly exists as thorium phosphate (76%) and thorium oxide (24%), with minor amounts of thorium silicate also detected. This study provides quantitative and qualitative information on thorium mineral phases in soil samples from Sri Lanka using XAS for the first time.
SCIENTIFIC REPORTS
(2023)
Article
Materials Science, Multidisciplinary
Nicolas Finck, Nikoleta Morelova, Michel L. Schlegel, Dieter Schild, Solenn Reguer, Kathy Dardenne, Horst Geckeis
Summary: The stainless steel AISI 309 S, used for containers of vitrified high-level radioactive waste, was subjected to 90 degrees C under highly saline and anoxic conditions for different exposure times up to 294 days. The surface damage was minimal, and no pitting was observed. The corrosion layer consisted of an inner layer comprising mostly chromium (hydr)oxides and an outer layer composed of Fe- and Ni-based spinel compounds with admixed nickel (hydr)oxides. Minor amounts of magnetite and layered double hydroxide were also identified. Dissolved metal ion concentrations were very low, with only a slight increase in pH and limited decrease in redox potential.
Article
Chemistry, Multidisciplinary
Si Chen, Xiaohui Huang, Dieter Schild, Di Wang, Christian Kuebel, Silke Behrens
Summary: Intermetallic Pd-In nanoparticles were synthesized in ionic liquids using a novel and facile approach. The structure of the nanoparticles obtained under different reaction conditions was confirmed. These stabilized nanoparticles showed high activity and selectivity as catalysts. This research provides insights for the synthesis of intermetallic nanoparticles and the design of bimetallic catalysts.