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Green synthesis of micro/nanomaterials, using glycerol as a sustainable solvent, offers environmentally and health-friendly pathways. Glycerol’s versatility in a solvothermal synthesis is effective for nanoparticle production, yet its mechanistic role in carbonate material formation is unexplored. This study investigates urchin-like strontium carbonate formation via a glycerol-mediated solvothermal synthesis, employing in situ transmission electron microscopy (in situ TEM), scanning electron microscopy, density function theory (DFT), scanning transmission electron microscopy, and X-ray diffraction. In situ TEM observations unveil the initial stages of strontium hydroxide nucleation and subsequent growth as an intermediate phase. The findings suggested that the hyperbranched polymerization of glycerol plays a pivotal role in the formation of urchin-like morphology. Furthermore, the synergistic effect of glycerol and CO2 is proposed as the primary driver for the formation of strontium carbonate. Notably, observations showed a morphological transition from spherical to urchin-like with increasing reaction time. DFT studies proposed glycerol as a coadsorbent, boosting the adsorption energy of CO2 and directing its interaction with Sr(OH)2 resulting in the stable formation of SrCO3. This research provides valuable insights into the urchin-like strontium carbonate formation in a time-dependent process driven by the polymerization of glycerol and its high reactivity with dissolved CO2 at elevated temperatures. 

Dendritic growth of lithium (Li) is hindering potential applications of Li-metal batteries, and new approaches are needed to address this challenge. The confinement effect of two-dimensional materials triggered by strong molecular interactions between parallelly-aligned graphene oxide (GO) at Li metal interface is proposed here as a new strategy to suppress the dendritic growth of Li. The effectiveness of aligned GO for Li-metal cells is shown for two different polymer separator cells:liquid electrolytes with porous propylene (PP) separators and solid polyethylene oxide (PEO) electrolytes. For the case of liquid electrolytes, PP separators were modified with plasma treatment to induce the alignment of GO layers. The Li‖Li cells with aligned GO illustrate a stable Li platting/stripping (up to 1000 cycles). The Li‖lithium iron phosphate (LFP) battery cells with aligned GO could cycle at 5C for 1000 cycles (∼90% capacity retention). For solid polymer electrolyte (SPE) cells, GO–Li confinement effect is also effective in Li dendrites suppression enhancing the stability and lifespan of Li-metal batteries. The Li‖LFP cell with the GO-modified SPE showed ∼85% capacity retention after 200 cycles at 1C. Such combined high rate capability and number of cycles exceeds the previously reported performances for both liquid and SPE-based Li‖LFP cells. This points to a new opportunity for utilizing the confinement effect of two-dimensional materials for the development of next generation, fast rate rechargeable Li batteries.