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Electrochemically Enhanced Dissolution of Silica and Alumina in Alkaline Environments
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Atomic Dislocations and Bond Rupture Govern Dissolution Enhancement under Acoustic Stimulation
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Drastic Modulation of Molecular Packing and Intrinsic Dissolution Rates by Meniscus-Guided Coating o
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Enhanced LiMn 2 O 4 Thin-Film Electrode Stability in Ionic Liquid Electrolyte: A Pathway to Suppress Mn Dissolution
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Morphology-Controlled Discharge Profile and Reversible Cu Extrusion and Dissolution in Biomimetic CuS
Metal sulfides, such as CuS, SnS2, Co9S8, MoS2, are high capacity anode materials for Li-ion batteries. However, these materials go through a conversion reaction with Li+, which is accompanied by the phase transformation and inevitably results in a huge volume expansions, therefore causing performance degradation. Here, we report nanoscale engineering route to efficiently control the overall volume expansion for enhanced performance. We engineered CuS with nanoplate assembly on a nanostring, leading to a nanostructure of mimicking the crassula baby necklace (CBN) in the natural plant. Using in-situ transmission electron microscopy (in-situ TEM), we probed the lithiation kinetics and dynamic structural transformations. Due to the linkage of the central nanostring, the CuS CBN exhibited fast Li+ diffusion along the axial direction and high mechanical stability during lithiation. The volume expansion was minimal for the CuS CBN due to the pre-engineered gap between these plates. The CuS followed a two-step lithiation process with Cu2S and Li2S formation as the first step and Cu extrusion from Cu2S in the later stage. Interestingly, during the Cu2S to Cu conversion, there was a incubation period before the metallic Cu extrusion, which is featured by the formation of an amorphous structure due to the large lattice strain and distortion associated with the displacement of Cu by Li ions. In the final stage, the lithiated amorphous phase recrystallized to a composite of Cu nanocrystals dispersed in a polycrystalline Li2S matrix. Associate with the nanoscale size, the Cu nanocrystals can reversibly dissolve into the matrix upon delithiation. The present work demonstrates tailoring of desired functionality through nanoscale engineering of using bionic methods.
Hematite Crystallization in the Presence of Organic Matter: Impact on Crystal Properties and Bacterial Dissolution
Abstract not provided
Effects of Phosphate, Silicate, and Bicarbonate on Arsenopyrite Dissolution and Secondary Mineral Precipitation
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Interfacial Electrochemical Lithiation and Dissolution Mechanisms at a Sulfurized Polyacrylonitrile Cathode Surface
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Solvent Dynamics Are Critical to Understanding Carbon Dioxide Dissolution and Hydration in Water
Simulations of carbon dioxide (CO 2 ) in water may aid in understanding the impact of its accumulation in aquatic environments and help advance technologies for carbon capture and utilization (via, e.g., mineralization). Quantum mechanical (QM) simulations based on static molecular models with polarizable continuum solvation poorly reproduce the energetics of CO 2 hydration to form carbonic acid in water, independent of the level of QM theory employed. Only with density-functional-theory-based molecular dynamics and rare-event sampling, followed by energy corrections based on embedded correlated wavefunction theory (in conjunction with density functional embedding theory), can a close agreement between theory and experiment be achieved. Such multilevel simulations can serve as benchmarks for simpler, less costly models, giving insight into potential errors of the latter. The strong influence of sampling/averaging over dynamical solvent configurations on the energetics stems from the difference in polarity of both the transition state and product (both polar) versus the reactant (nonpolar). When a solute undergoes a change in polarity during reaction, affecting its interaction with the solvent, careful assessment of the energetic contribution of the solvent response to this change is critical. Here, we show that static models (without structural sampling) that incorporate three explicit water molecules can yield far superior results than models with more explicit water molecules because fewer water molecules yield less configurational artifacts. Static models intelligently incorporating both explicit (molecules directly participating in the reaction) and implicit solvation, along with a proper QM theory, e.g., CCSD(T) for closed-shell systems, can close the accuracy gap between static and dynamic models.
Chelation-Driven Chemistry Controls Dissolution Pathways for Facile Critical Mineral Recovery from Ultramafic Resources
The efficient recovery of critical minerals, such as nickel (Ni) and manganese (Mn) from the subsurface is of vital importance, given their role in modern technologies ranging from batteries to advanced alloys. This study explores an approach that employs chelation to enhance critical mineral recovery from ultramafic rocks using chelating ligands under ambient pressures and systematically evaluates the extraction process for the first time. Experimental results demonstrate the superior performance of EDTA and PrDTA in achieving high extraction efficiencies for both Ni and Mn. To further highlight the ability for optimization, the fluid exchange and variation of fluid-to-rock ratio experiments were conducted, revealing tunable controls for engineering recovery. We show that under optimized conditions, a Ni extraction efficiency of ?82% and a Mn extraction efficiency of ~60% is achieved at ambient pressures, which is equivalent to over 23 times the current global Ni production, and 2 million metric tonnes (MMT) greater than the current global Mn production. From both in-situ and ex-situ mining perspectives, the results highlight the potential of chelation to advance sustainable mineral processing. Overall, this work highlights the environmental benefits of innovative ligand-assisted recovery methods, addressing the critical need for the efficient utilization of olivine resources.
The effectiveness of TRIS and ammonium buffers in glass dissolution studies: a comparative analysis
Abstract Selecting appropriate buffers is crucial for evaluating the chemical durability of glass under controlled conditions such as in the EPA 1313 test designed to measure elemental release as a function of pH. The efficacy of two alkali-metal free buffers, TRIS (NH 2 C(CH 2 OH) 3 ) and ammonium chloride—ammonia (NH 3 /NH 4 Cl), was investigated during EPA 1313 testing of a simulated Hanford low-activity waste borosilicate glass in the alkaline regime (pH 8.5–10.5) at varying temperatures (RT, 40 °C, and 60 °C). While both buffers maintained the desired pH at room temperature, and up to 40 °C, the effectiveness of TRIS decreased at elevated temperatures, particularly at pH 10.5. Although 11 B NMR showed evidence of TRIS-B complexation, its effect on the rate of elemental release was found to be negligible under the test conditions. With ammonium buffer, the release of alkali cations was slightly elevated when compared to the same conditions with TRIS at early time points.
An electrochemical technique for controlled dissolution of zirconium based components of light water reactors
This work demonstrates a controlled potential electrochemistry with correlative microscopy for insight into the radial H-distribution into TPBAR components of light water reactors.
Control of aggregation and dissolution of small molecule hole transport layers via a doping strategy for highly efficient perovskite solar cells
Polymeric dopant strategy distinctly suppressed the molecular aggregations and surface dewetting of the NPB small molecule hole transport layer in perovskite photovoltaics.