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Novel binder-free, high capacity carbon-based anodes were manufactured using Virtual Cathode Deposition technique in an industrially scalable process. The deposition process transformed a commercial graphite target material into a novel carbon polymorph coating, which was used as Li-ion battery anode. Such anodes displayed first cycle specific capacity of ~ 1250 mAh g-1 and retained a capacity of more than 900 mAh g-1 at 0.1C rate and more than 600 mAh g-1 at 0.5 A.g-1 rate during cycling. Coulombic efficiencies above 99.5% were attained for 500 cycles. The anodes showed excellent volumetric (>1400 Ah L-1) and areal capacity (~ 4.5 mAh cm-2). Detailed structural characterisation revealed controllably induced packing polymorphism and high surface area (~ 2100 m² g-1). The hierarchical architecture of the coatings was composed predominantly of meso- and macro-pores observed in a disordered carbon matrix encompassing nano-sized sp2-clusters (average size ~ 15-20 nm) cross-linked by a network of sp3-bonded atomic sites. A growth model based on the subsurface implantation mechanism was adopted to explain the formation of this unique structure responsible for the measured high specific capacity and good Coulombic efficiency.

We study the effects of investor disagreement on informed trading by activist investors using high-frequency disagreement data derived from the investor social network StockTwits. Greater investor disagreement leads to more trading activity on the subsequent day by privately informed activists. Disagreement leads to higher prices and improvements in measured liquidity, but these observed valuation and market liquidity differences do not explain the increase in activist trading. Instead, investor disagreement affects activist trading primarily by facilitating trading by non-activist investors. These findings suggest that investor disagreement not only affects trading by uninformed investors but also facilitates trading by informed market participants who often take actions aimed at changing corporate policies.

We find evidence of selective exposure to confirmatory information among 400,000 users on the investor social network StockTwits. Self-described bulls are 5 times more likely to follow a user with a bullish view of the same stock than self-described bears. Consequently, bulls see 62 more bullish messages and 24 fewer bearish messages than bears over the same 50-day period. These “echo chambers” exist even among professional investors and are strongest for investors who trade on their beliefs. Finally, beliefs formed in echo chambers are associated with lower ex-post returns, more siloing of information and more trading volume.