We report the preparation of ordered porous carbon materials with tailored pore sizes selected between 16 and 108 nm using bottlebrush block copolymers (BBCPs) as templates. The nanoporous carbons are prepared via the cooperative assembly of polydimethylsiloxane-block-poly(ethylene oxide) (PDMS-b-PEO) BBCPs with phenol−formaldehyde resin yielding ordered precursor films, followed by carbonization. The assembly of PDMS-b-PEO BBCPs with the resin leads to films exhibiting a spherical morphology (PDMS as the minor domain) with uniform domain sizes between 18 and 150 nm in the bulk. The assembled PDMS sphere diameters scale linearly with BBCPs molecular weights, allowing precise control of domain size. Access to very large ordered domains is an enabling hallmark of BBCPs self-assembly, but reports of well-ordered spherical domains are not common. Carbonization of the ordered precursor films yields nanoporous carbon with uniform and tunable pore size. These nanoporous carbons are shown to exhibit excellent performance as supercapacitor electrodes with capacitance reaching up to 254 F g −1 at a current density of 2 A g −1 .

We report the synthesis of a bottlebrush statistical copolymer (BSCP) architecture and its role in directing molecular packing in the bulk state. Copolymers with a statistical distribution of two chemically distinct side chains on a common polymer backbone were prepared via one-pot ring-opening metathesis polymerization (ROMP) of norbornene-capped macromonomers with similar reactivities. Kinetic studies suggest a near-random compositional profile of polystyrene (PS) and poly­(dimethyl siloxane) (PDMS) side chains along the backbone. The PS-stat-PDMS BSCPs with symmetric volume fractions rapidly assembled into lamellar microstructures when cast from solution without any further thermal or solvent annealing. The domain size is controlled by the side-chain length, ranging from below 10 nm to almost 20 nm. Furthermore, the bottlebrush statistical copolymer self-assembly yielded oriented lamellar morphologies over large areas after thermal annealing for 10 min at 200 °C without external guiding via surface or topographic patterning. Such statistical architectural control of the composition enables a simple preparation route for copolymers for potential use in the directed self-assembly of device architectures and other applications that require well-defined morphologies.

We report the preparation of hierarchically ordered porous carbon films with ∼5 nm mesopores distributed within a continuous carbon framework surrounding ∼100 nm macropores. The hierarchical carbons are prepared using bottlebrush block copolymers (BBCP) of large molecular weight (M w = 1800 kg mol −1 ), low-molecular-weight linear block copolymers (LBCPs), and phenolformaldehyde resin, which cooperatively assemble to yield "planet−satellite" morphologies following carbonization. The combination of BBCPs and LBCPs as co-templates enables a generalized strategy to design functional materials in which the pore sizes of both the mesopores and macropores are tuned within a continuous matrix and the mesopores uniformly surround macropores. The template is an ideal route for fabrication of tailored devices. The hierarchical carbon films exhibit exceptional performance as supercapacitor electrodes, with capacitance reaching up to C = 1420 mF cm −2 at 16 mA cm −2 (corresponding to 177 F g −1 at 2 A g −1 with mass loading 8 mg cm −2 ) resulting from a combination of high surface area and controlled pore structures. In such an application, the hierarchical carbons outperform devices that contain exclusively mesopores templated by the LBCP or only the macropores templated by the BBCP.

Carbonization by rapid thermal annealing (RTA) of precursor films structured by a brush block copolymer-mediated self-assembly enabled the preparation of large-pore (40 nm) ordered mesoporous carbon (MPC)-based micro-supercapacitors within minutes. The large pore size of the fabricated films facilitates both rapid electrolyte diffusion for carbon-based electric double-layer capacitors and conformal deposition of V2O5 without pore blockage for pseudocapacitors. The pores were templated using bottlebrush block copolymers (BBCPs) via cooperative assembly of phenol-formaldehyde resin to produce microphase-segregated carbon precursor films on a variety of substrates. Ultrafast RTA processing (∼50 °C/s) at elevated temperatures (up to 1000 °C) then generated stable, conductive, turbostratic MPC films, resolving a significant bottleneck in rapid fabrication. MPC prepared on stainless steel at 900 °C demonstrated exceptionally high areal and volumetric capacitances of 6.3 mF/cm2 and 126 F/cm3 (at 0.8 mA/cm2 using 6 M KOH as the electrolyte), respectively, and 91% capacitance retention after 10,000 galvanostatic charge/discharge cycles. Post-RTA conformal V2O5 deposition yielded pseudocapacitors with 10-fold increase in energy density (20 μW h cm–2 μm–1) without adversely affecting the high power density (450 μW cm–2 μm–1). The use of RTA coupled with BBCP templating opens avenues for scalable, rapid fabrication of high-performance carbon-based micro-pseudocapacitors.

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