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 .

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.

Silicon carbide (SiC) and silicon oxycarbide (SiOC) ceramic/carbon (C) nanocomposites are prepared via photothermal pyrolysis of cross-linked polycarbosilanes and polysiloxanes using a high-intensity pulsed xenon flash lamp in air at room temperature to yield crystalline and amorphous phases of SiC and SiOC ceramics, graphitic, and amorphous carbon phases. The millisecond duration of the radiation pulse is shorter than the thermal equilibrium time of the preceramic polymers (PCPs), enabling pyrolysis of the precursor phase and crystallization of the product before significant energy transfer to the substrate, making this process uniquely amenable to ceramic processing on or adjacent to thermally sensitive materials. Rapid precursor pyrolysis and product crystallization during flash lamp processing, even in air, limit oxidation of the resulting ceramics. To prepare the nanocomposites, PCPs are coated onto woven carbon fiber fabrics, thermally cross-linked, and then flash-lamp-pyrolyzed. The resulting nanocomposites are thermally and oxidatively stable at extremely high temperatures. The nanocomposites exhibit excellent performance as supercapacitor electrodes with capacitance as high as 27.2 mF/cm2 at a 10 mV/s scan rate at room temperature, excellent stability over 1000 cycles, and Coulombic efficiency of 80%. Patterned nanocomposites are prepared via nanoimprint lithography, followed by photothermal processing of precursor films. These nanocomposites have potential applications in energy storage, catalysis, and separations.

We demonstrate SDN-controlled dynamic front-haul optical network pro visioning and modulation format adaptation, running on an emulation of the COSMOS testbed benchmarked against the COSMOS hardware testbed.

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We report a method for fast, efficient, and scalable preparation of high-quality, large area, few-layer graphene films on arbitrary substrates via high-intensity pulsed xenon flash lamp photothermal pyrolysis of thin precursor films at ambient conditions in millisecond time frames. The precursors comprised poly(2,2-bis(3,4-dihydro-3-phenyl-1,3-benzoxazine)), and cyclized polyacrylonitrile and possess significant absorption cross section within the bandwidth of the emission spectrum of a xenon flash lamp. By localizing light absorption to the precursor films, the process enabled the preparation of few-layer graphene films on any substrate, including thermally sensitive substrates without the need for any catalytic substrate as in chemical vapor deposition-based approaches or conductive electrodes as in electrochemical methodbased approaches. The extent of conversion of the precursor films to graphene was strongly dependent on pulse energy and the local temperature achieved due to photothermal effect, which were controlled via pulse power modulation; it also depended on structural properties of the precursor and to a lesser extent on the substrate. The cPAN showed a higher efficiency for conversion to graphene, as confirmed by Raman spectra (I D /I G ∼ 0.3), and sheet resistance of 0.1 Ω cm. To demonstrate the utility of the process, graphene film electrodes prepared photothermally on carbon fiber current collector were used for the fabrication of micro-supercapacitors with a very high areal supercapacitance of 3.5 mF/cm 2 . Subsequent deposition of manganese oxide onto the fabricated electrodes significantly increased the energy storage capability of the supercapacitor, yielding a device with exceptionally high capacitance of 80 F/g at 1 mA current, good rate capability, and long cycle life.

We analyze an optical control plane algorithm designed to operate in real-time to improve generalized-optical signal-to-noise ratio (gOSNR) quality-of-transmission-estimation (QoT-E), based on OSNR monitoring. We report QoT-E performance improvements of up to 1 dB.