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Abstract Existing pathways to produce graphite which include extraction of natural graphite impact the environment, while the conversion of fossil-driven carbon to graphite around temperatures as high as 3000 °C consumes large quantities of energy. Potassium - catalyzed graphitization is a more sustainable route and can achieve graphitic carbon formation at temperatures lower than 1000 °C, while enhancing pore formation and creating porous graphitic carbon (PGC). This two-step approach involves carbonization followed by graphitization. However, the compositions of the gaseous products have not been reported in prior studies. In this perspective, the chemical transformations underlying Alkaline Thermal Graphitization (ATG) for the co-production of synthesis gas (H₂and CO) and PGC in a single step, utilizing lignocellulosic biomass, are reported. The presence of graphitic and porous carbon structures in PGC are well suited for supercapacitor applications. This promising approach maximizes resource recovery by upgrading volatile matter to synthesis gas and low value biomass residues to porous graphitic carbon (PGC), thus co-producing sustainable fuels and energy storage materials, while lowering CO₂emissions compared to existing pathways to produce graphite. 

The use of calcium bearing resources to facilitate solvent regeneration and CO2 reuse via carbon mineralization offers a low energy pathway for the production of calcium carbonate. However, a crucial challenge is the lack of specificity in the formation of various calcium carbonate polymorphs during carbon mineralization. One of the less explored but highly effective approaches to tune the morphology and crystal structure of specific carbonate phases involves tuning vortex flows. This approach is an alternative to utilizing chemical reagents that need to be regenerated for tuning the morphologies and crystalline structures to direct the formation of specific carbonate phases. In this study, the efficacy of using homogeneous vortex flows in limiting the agglomeration of carbonate particles and directing the formation of metastable vaterite phases is discussed and contrasted with the influence of inhomogeneous conventional feed flow patterns on precipitated calcium carbonate (PCC). Herein, a TaylorCouette Carbonate Conversion (TC3 ) reactor is used to direct the formation of spherical vaterite particles with uniform particle size distribution preferentially over calcite and other phases. The formed vortex patterns inside TC3 reactor provide homogeneous reaction spaces conducive to PCC formation, ensuring uniform mixing throughout the process. By increasing the rotational speed and the residence time, higher purity carbonates with more uniform sizes are obtained. Furthermore, preferential vaterite formation is also observed in leachates obtained from alkaline industrial residues such as construction and demolition waste and steel slag. Thus, the proposed approach is effective in harnessing multiple waste streams such as CO2 emissions and alkaline industrial residues to produce calcium carbonate phases such as vaterite with structural and morphological specificity. 

Mechanisms underlying co-recovery of energy critical metals and carbon mineralization by harnessing organic ligands are uncovered by investigating the influence of chemical and mineral heterogeneity and the morphological transformations of minerals. 

Solid-state electrolytes (SSEs) are challenged by complex interfacial chemistry and poor ion transport through the interfaces they form with battery electrodes. Here, we investigate a class of SSE composed of micrometer-sized lithium oxide (Li₂O) particles dispersed in a polymerizable 1,3-dioxolane (DOL) liquid. Ring-opening polymerization (ROP) of the DOL by Lewis acid salts inside a battery cell produces polymer-inorganic hybrid electrolytes with gradient properties on both the particle and battery cell length scales. These electrolytes sustain stable charge-discharge behavior in Li||NCM811 and anode-free Cu||NCM811 electrochemical cells. On the particle length scale, Li₂O retards ROP, facilitating efficient ion transport in a fluid-like region near the particle surface. On battery cell length scales, gravity-assisted settling creates physical and electrochemical gradients in the hybrid electrolytes. By means of electrochemical and spectroscopic analyses, we find that Li₂O particles participate in a reversible redox reaction that increases the effective CE in anode-free cells to values approaching 100%, enhancing battery cycle life. 

Reaction pathways & configurations to upcycle aqueous biomass oxygenates and large amounts of low value calcium & magnesium bearing sources over Ni and Pt catalyst to produce high value H₂with inherent CO₂removal in a single step was explored.