No abstract

The commercialization of the silicon (Si) anode has been hindered by the instability of its solid-electrolyte interphase (SEI), yet a comprehensive understanding of SEI properties remains underdeveloped owing to the challenge of characterizing this nanoscale passivation layer. In this work, we visualize the structure and chemistry of the SEI on silicon anodes using atomic-resolution cryogenic (scanning) transmission electron microscopy (cryo-(S)TEM) and electron energy loss spectroscopy (EELS), revealing its evolution over the first cycle. We discover the origin of the Si SEI instability in ethylene carbonate (EC) electrolytes, owing to the high reversibility of the SEI. The role of the critical electrolyte additive fluoroethylene carbonate is revealed, which extends the cyclability of the Si anode through deposition of an electrochemically irreversible polycarbonate layer on the anode surface. These findings provide a nuanced view into the Si anode instability in commercial EC-based electrolytes and the role of additives for SEI stabilization.

Using the competing agency theoretic and stewardship theory perspectives, we empirically examine the relationship between CEO duality and firm performance in family‐controlled public firms (FCPFs). We find that duality by itself does not influence firm performance in FCPFs. However, our results show that the relationship between duality and performance is contingent on the family's ownership stake in the firm. In nondual firms, performance is inversely related to family ownership level. Dual FCPFs do not exhibit any changes in performance dependent on family ownership levels. Our findings reveal, in short, that when family ownership is low, the separation of CEO and board chair roles is beneficial in terms of shareholder returns. Having different persons occupy the CEO and board chair positions is a useful governance control as the risk of family entrenchment increases.