The development of efficient catalysts for Fischer–Tropsch (FT) synthesis, a core reaction in the utilization of non-petroleum carbon resources to supply energy and chemicals, has attracted much recent attention. ε-Iron carbide (ε-Fe2C) was proposed as the most active iron phase for FT synthesis, but this phase is generally unstable under realistic FT reaction conditions (> 523 K). Here, we succeed in stabilizing pure-phase ε-Fe2C nanocrystals by confining them into graphene layers and obtain an iron-time yield of 1258 μmolCO gFe−1s−1 under realistic FT synthesis conditions, one order of magnitude higher than that of the conventional carbon-supported Fe catalyst. The ε-Fe2C@graphene catalyst is stable at least for 400 h under high-temperature conditions. Density functional theory (DFT) calculations reveal the feasible formation of ε-Fe2C by carburization of α-Fe precursor through interfacial interactions of ε-Fe2C@graphene. This work provides a promising strategy to design highly active and stable Fe-based FT catalysts.

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Exploring efficient energy systems with integrated energy harvesting and storage toward sustainable power sources is an extremely promising solution for alleviating the energy crisis but nevertheless remains an arduous challenge. Here, a high‐efficient self‐charging power system (SCPS) by integrating solid‐state asymmetric supercapacitors device (SASD) and rotational triboelectric nanogenerator (RTENG) to achieve efficient energy harvesting and storage is reported. Dual redox active sites Ni2P/NiSe2 heterostructure is homogeneously inlaid on N‐C (N‐C@Ni2P/NiSe2) via an in situ phosphoselenization, which achieves the maximum exposure of active sites and prevents the aggregation of nanoparticles. The ingeniously designed N‐C@Ni2P/NiSe2 heterostructure features high activity dual redox sites, well‐defined heterointerface, and stable superhighway conductive support, which facilitates high electrochemical reaction efficiency, accelerated reaction kinetics, and enhanced electrochemical stability, thus achieving high capacitance and excellent stability. Meanwhile, the SASD delivers high energy density and long lifespan. Furthermore, the RTENG exhibits high output performance, enabling efficient energy harvesting. The SCPS can reach a voltage of 3.8 V within 40 s, and continuously power electronics. It is believed that the proposed survey based on the design and integration of dual redox active sites heterostructure will offer a new prospect for next‐generation sustainable power sources.

Spotify is a Swedish digital music streaming service and technology company founded in 2006 by Daniel Ek. In the US market, Spotify is the most predominant audio streaming service among its competitors. The primary purpose of this research was to explore how Spotify took advantage of its branding culture to deliberately orient or mediate its customer engagement. This research would develop preceding case studies related to customer engagement and Spotify's branding strategies to draw a general correlation. Although psychological factors of the consumers might affect their engagement to a certain extent, the research concludes the personalized customer experience of Spotify has strengthened the relationship between the application and consumers, attracting more non-members to subscribe to the premium service offered by Spotify. From Spotify's data-driven service, a particular customized playlist would be recommended to the users. People tend to be touched by music and such emotional interactions, leading to a sense of resonation and inspiration to them. Besides, artists and other music content creators could better comprehend the streaming media data of their works through the analytic database from Spotify. The adhesiveness of users would be valued. Thus, Spotify's brand culture and marketing tactics have to render part of its consumers become advocates, extensively spreading word-of-mouth recommendations of Spotify's benefits. In short, this research aims to provide an enlightening indication of Spotify's prospective developing orientation, which might be facilitated customer-oriented innovativeness.