Direct-Chemical Vapor Deposition-Enabled Graphene for Emerging Energy Storage: Versatility, Essentiality, and Possibility

The direct chemical vapor deposition (CVD) technique has stimulated an enormous scientific and industrial interest to enable the conformal growth of graphene over multifarious substrates, which readily bypasses tedious transfer procedure and empowers innovative materials paradigm. Compared to the prevailing graphene materials (i.e., reduced graphene oxide and liquid-phase exfoliated graphene), the direct-CVD-enabled graphene harnesses appealing structural advantages and physicochemical properties, accordingly playing a pivotal role in the realm of electrochemical energy storage. Despite conspicuous progress achieved in this frontier, a comprehensive overview is still lacking by far and the synthesis-structure-property-application nexus of direct-CVD-enabled graphene remains elusive. In this topical review, rather than simply compiling the state-of-the-art advancements, the versatile roles of direct-CVD-enabled graphene are itemized as (i) modificator, (ii) cultivator, (iii) defender, and (iv) decider. Furthermore, essential effects on the performance optimization are elucidated, with an emphasis on fundamental properties and underlying mechanisms. At the end, perspectives with respect to the material production and device fabrication are sketched, aiming to navigate the future development of direct-CVD-enabled graphene en-route toward pragmatic energy applications and beyond.