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A tandem (two‐step) particle swarm optimization (PSO) algorithm is implemented in the argyrodite‐based multidimensional composition space for the discovery of an optimal argyrodite composition, i.e., with the highest ionic conductivity (7.78 mS cm−1). To enhance the industrial adaptability, an elaborate pellet preparation procedure is not used. The optimal composition (Li5.5PS4.5Cl0.89Br0.61) is fine‐tuned to enhance its practical viability by incorporating oxygen in a stepwise manner. The final composition (Li5.5PS4.23O0.27Cl0.89Br0.61), which exhibits an ionic conductivity (σion) of 6.70 mS cm−1 and an activation barrier of 0.27 eV, is further characterized by analyzing both its moisture and electrochemical stability. Relative to the other compositions, the exposure of Li5.5PS4.23O0.27Cl0.89Br0.61 to a humid atmosphere results in the least amount of H2S released and a negligible change in structure. The improvement in the interfacial stability between the Li(Ni0.9Co0.05Mn0.05)O2 cathode and Li5.5PS4.23O0.27Cl0.89Br0.61 also results in greater specific capacity during fast charge/discharge. The structural and chemical features of Li5.5PS4.5Cl0.89Br0.61 and Li5.5PS4.23O0.27Cl0.89Br0.61 argyrodites are characterized using synchrotron X‐ray diffraction, Raman spectroscopy, and X‐ray photoelectron spectroscopy. This work presents a novel argyrodite composition with favorably balanced properties while providing broad insights into material discovery methodologies with applications for battery development. [ABSTRACT FROM AUTHOR]

It has recently been observed that benzoic acid strongly reacts with OH group on the silicon surface. Here, by defining the area in which OH group is adsorbed on the Si surface, the selective adsorption of benzoic acid species was attempted. The patterned OH/Si surface was prepared by irradiating the zeroth order beam from the bending magnet of the synchrotron facility through the gold mesh placed in front of the OH/Si sample. For discerning the selectively adsorbed molecule by x-ray photoelectron emission microscopy (X-PEEM) at N k edge, 4-nitrobenzoic acid was utilized instead of benzoic acid. Near edge x-ray absorption fine structure spectra at carbon and oxygen k edges were in good accord with the previous results obtained from the benzoic acid system. The X-PEEM images around N k edge clearly showed that the molecules adsorb only on the area in which OH groups remain. [ABSTRACT FROM AUTHOR]