How surface chemistry influences reactions occurring thereupon has been a long-standing question of broad scientific and technological interest. Here, we consider the relation between the surface chemistry at interfaces and the reversibility of electrochemical transformations at rechargeable battery electrodes. Using Zn as a model system, we report that a moderate strength of chemical interaction between the deposit and the substrate—neither too weak nor too strong—enables highest reversibility and stability of the plating/stripping redox processes. Focused ion beam and electron microscopy were used to directly probe the morphology, chemistry, and crystallography of heterointerfaces of distinct natures. Analogous to the empirical Sabatier principle for chemical heterogeneous catalysis, our findings arise from competing interfacial processes. Using full batteries with stringent negative electrode–to–positive electrode capacity (N:P) ratios, we show that such knowledge provides a powerful tool for designing key materials in highly reversible battery systems based on Earth-abundant, low-cost metals such as Zn and Na.

Chemical conversion coating as an effective corrosion inhibition has wide range of applications in industries and is of great expectation to be environmentally friendly and cost effective. Zirconium (Zr)-based conversion coating using hexafluorozirconic acid with copper (Cu) additive on low carbon steel which improves anti-corrosion and adhesion properties is studied using synchrotron X-ray and electron-based techniques. To understand the elemental evolution during coating formation process, in situ synchrotron X-ray fluorescence (XRF) microscopy has been applied to observe Zr, Cu, iron (Fe) and zinc (Zn) concentration evolution. By quantifying the density, average size and size distribution of the cluster as a function of time and temperature, the growth mechanism of the coating can be concluded as a reaction-controlled mechanism. X-ray Absorption Near Edge Structure and X-ray photoelectron spectroscopy (XPS) were used to characterize the composition of the Cu-rich clusters embedded in the coating was determined to be mainly Cu₂O, Cu and CuF₂; the cluster composition varies from the surface to the internal region as determined by the depth-profiling of XPS. Our study shed light on the chemical and morphological evolution in environmentally friendly surface conversation coating and demonstrated new methodology in studying the coating formation via in situ Synchrotron XRF.

We report discovery of antiferromagnetic semimetal ${\mathrm{EuZnSb}}_2$, obtained and studied in the form of single crystals. Electric resistivity, magnetic susceptibility, and heat capacity indicate antiferromagnetic order of Eu with $T_N$ = 20 K. The effective moment of ${\mathrm{Eu}}^{2+}$ inferred from the magnetization and specific heat measurement is 3.5 ${\mu }_B$, smaller than the theoretical value of ${\mathrm{Eu}}^{2+}$ due to presence of both ${\mathrm{Eu}}^{3+}$ and ${\mathrm{Eu}}^{2+}$. Magnetic-field-dependent resistivity measurements suggest dominant quasi-two-dimensional Fermi surfaces whereas the first-principle calculations point to the presence of Dirac fermions. Therefore, ${\mathrm{EuZnSb}}_2$ could represent the first platform to study the interplay of dynamical charge fluctuations, localized magnetic $4f$ moments, and Dirac states with Sb orbital character.

Artemisinin and its derivatives are the well-known anti-malarial drugs derived from a traditional Chinese medicine. In addition to antimalarial, artemisinin and its derivatives possess distinguished anti-cancer, anti-oxidant, anti-inflammatory and anti-viral activities, but the poor solubility and low bioavailability hinder their clinical application. In the last decades a series of new water-soluble and oil-soluble derivatives were synthesized. Among them, we have found a water-soluble derivative β-aminoarteether maleate (SM934) that exhibits outstanding suppression on lymphocytes proliferation in immunosuppressive capacity and cytotoxicity screening assays with 35-fold higher potency than dihydroartemisinin. SM934 displays significant therapeutic effects on various autoimmune and inflammatory diseases, including systemic lupus erythematosus, antiphospholipid syndrome nephropathy, membranous nephropathy, rheumatoid arthritis, multiple sclerosis, inflammatory bowel disease, and dry eye disease. Here, we summarize the immunomodulatory effects, anti-inflammatory, anti-oxidative and anti-fibrosis activities of SM934 in disease-relevant animal models and present the probable pharmacological mechanisms involved in its therapeutic efficacy. This review also delineates a typical example of natural product-based drug discovery, which might further vitalize natural product exploration and development in pharmacotherapy.