The ever‐increasing demand for stationary energy storage has driven the prosperous investigation of low‐cost sodium ion batteries. The inferior long‐term cycling stability of cathode materials is a significant roadblock toward the wide commercialization of sodium ion batteries. This study enlightens a path toward empowering stable sodium ion batteries through incisive diagnostics of the multiscale surface chemical processes in layered oxide materials (e.g., O3‐NaNi1/3Fe1/3Mn1/3O2). The major challenges are unraveled in a promising sodium layered cathode material using a range of complementary advanced spectroscopic and imaging diagnostic techniques. It is discovered that the cathode–electrolyte interfacial reaction triggers transition metal reduction, heterogeneous surface reconstruction, metal dissolution, and formation of intragranular nanocracks. These surface chemistry driven processes are partly responsible for significant performance decay. This diagnostic study also rationalizes the elemental substitution and surface passivation methods that are widely applied in the field. The prepassivated and Ti‐substituted cathode materials allow for significantly improved cycling stability by inhibiting the metal dissolution. Therefore, incisively diagnosing the interfacial chemistry not only creates scientific insights into understanding sodium cathode chemistry, but also represents an advance toward establishing universal interfacial design principles for all alkali metal ion cathode materials.

Chiral inorganic materials predated life on Earth, and their enantiospecific surface chemistry may have played a role in the origins of biomolecular homochirality. However, enantiospecific differences in the interaction energies of chiral molecules with chiral surfaces are small and typically lead to modest enantioselectivities in adsorption, catalysis, and chemistry on chiral surfaces. To yield high enantioselectivities, small energy differences must be amplified by reaction mechanisms such as autocatalytic surface explosions which have nonlinear kinetics. Herein, we report the first observations of superenantiospecificity resulting from an autocatalytic surface explosion reaction of a chiral molecule on a naturally chiral surface. R,R- and S,S-tartaric acid decompose via a vacancy-mediated surface explosion mechanism on Cu single crystal surfaces. When coupled with surface chirality, this leads to decomposition rates that exhibit extraordinarily high enantiospecificity. On the enantiomorphs of naturally chiral Cu(643)(R&S), Cu(17,5,1)(R&S), Cu(531)(R&S) and Cu(651)(R&S) single crystal surfaces, R,R- and S,S-tartaric acid exhibit enantiospecific decomposition rates that differ by as much as 2 orders of magnitude, despite the fact that the effective rates constants for decomposition differ by less than a factor of 2.

Although fullerenes were discovered nearly 35 years ago, scientists still struggle to isolate "single molecule" tubular fullerenes larger than C 90 . In similar fashion, there is a paucity of reports for pristine single-walled carbon nanotubes (SWNTs). In spite of Herculean efforts, the isolation and properties of pristine members of these carbonaceous classes remain largely unfulfilled. For example, the low abundance of spherical and tubular higher fullerenes in electric-arc extracts (<0.01−0.5%) and multiplicity of structural isomers remain a major challenge. Recently, a new isolation protocol for highly tubular f ullerenes, also called f ullertubes, was reported. Herein, we describe spectroscopic characterization including 13 C NMR, XPS, and Raman results for purified [5,5] fullertube family members, D 5h -C 90 and D 5d -C 100 . In addition, DFT computational HOMO−LUMO gaps, polarizability indices, and electron density maps were also obtained. The Raman and 13 C NMR results are consistent with semiconducting and metallic properties for D 5h -C 90 and D 5d -C 100 , respectively. Our report suggests that short [5,5] fullertubes with aspect ratios of only ∼1.5−2 are metallic and could exhibit unique electronic properties.

Biochar cation exchange capacity (CEC) is a key property central to better retention of soil nutrients and reduction of fertilizer runoff. This paper reports a breakthrough process to improve biochar CEC value by a factor of nearly 10 through biochar surface oxygenation by ozonization. The CEC value of the untreated biochar was measured to be anywhere between 14 and 17 cmol/kg. A 90 min dry ozonization treatment resulted in an increased biochar CEC value of 109−152 cmol/kg. Simultaneously, the biochar ozonization process resulted in a reduction of biochar pH from 9.82 to as low as 3.07, indicating the formation of oxygen-functional groups including carboxylic acids on biochar surfaces. Using the technique of X-ray photoelectron spectroscopy (XPS), the formation of oxygen-functional groups including carboxylic acids on biochar surfaces have been observed at a nanometer molecular scale following the ozonization treatment. The molar O/C ratio (0.31:1) on ozonized biochar surface as analyzed by XPS was indeed significantly higher than that (0.16:1) of the control biochar surface. The molar O/C ratio from the elemental analysis data also showed an increase from the nonozonized sample (0.077:1) to the dry-ozonized sample (0.193:1). Fourier-transform infrared (FTIR) spectroscopy analysis also showed an increase in the content of oxygen-functional groups in the form of carbonyl groups on biochar surfaces upon ozonization, which can also produce certain amount of oxygenated biochar molecular fragments that may be solubilized by liquid water, potentially leading to greater effects upon application of biochar in soil.

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