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The microblade cutting method, so-called SAICAS, is widely used to quantify the adhesion of battery composite electrodes at different depths. However, as the electrode thickness or loading increases, the reliability of adhesion values measured by the conventional method is being called into question more frequently. Thus, herein, a few underestimated parameters, such as friction, deformation energy, side-area effect, and actual peeing area, are carefully revisited with ultrathick composite electrodes of 135 μm (6 mAh cm−2). Among them, the existence of side areas and the change in actual peeling area are found to have a significant influence on measured horizontal forces. Thus, especially for ultrahigh electrodes, we can devise a new SAICAS measurement standard: 1) the side-area should be precut and 2) the same actual peeling area must be secured for obtaining reliable adhesion at different depths. This guideline will practically help design more robust composite electrodes for high-energy-density batteries.

In all-solid-state batteries, the electrode has been generally fabricated as a composite of active material and solid electrolyte to imitate the electrode of lithium-ion batteries employing liquid ...

We report the nano-sized CuSO4–carbon nanotube composite (nano-CuSO4/C) as a novel conversion-based cathode material for Na-ion batteries (NIBs). The nano-CuSO4/C undergoes a conversion reaction during the charge/discharge process with a high redox potential of ~2.7 V (vs. Na+/Na) and the highest reported energy density for NIB cathode materials. Nano-CuSO4/C exhibits excellent electrochemical performance, with a specific capacity of ~335 mAh g−1 at a rate of C/30 (1C = 335 mA g−1), and even at 5C, its capacity is maintained up to ~204 mAh g−1, corresponding to ~61% of the theoretical capacity. Furthermore, nano-CuSO4/C delivers outstanding capacity retention of ~72% over 300 cycles at 2C with high coulombic efficiency of more than 99%. We confirm the reversible sodium storage mechanism on nano-CuSO4/C under Na-ion battery system using various analyses, such as operando/ex situ X-ray diffraction, X-ray absorption near edge structure spectroscopy, extended X-ray absorption fine structure spectroscopy, transmission electron microscopy, and time-of-flight secondary-ion mass spectroscopy. CuSO4 is transformed into Cu0 and Na2SO4 during the discharge (reduction) process, and the original CuSO4 is recovered during the charge (oxidation) process. This fundamental understanding of CuSO4 provides insight for the use of high-capacity conversion-based cathode materials in NIBs.

Volumetric energy density is considered a primary factor in developing high-energy batteries. Despite its significance, less efforts have been devoted to its improvement. Silicon-based materials have emerged as next-generation anodes for lithium-ion batteries due to their high specific capacity. However, their volumetric capacities are limited by the volume expansion rate of silicon, which restricts mass loading in the electrodes. To address this challenge, we introduce porous silicon templated from earth-abundant minerals with native internal voids, capable of alleviating volumetric expansion during repeated cycles. In situ transmission electron microscopy analysis allows the precise determination of the expansion rate of silicon, thus presenting an analytical model for finding the optimal content in silicon/graphite composites. The inner pores in silicon reduce problems associated with its expansion and allow higher silicon loading of 42% beyond the conventional limitations of 13-14%. Consequently, the anode designed in this work can deliver a volumetric capacity of 978 mAh cc

All‐solid‐state batteries are promising energy storage devices in which high‐energy‐density and superior safety can be obtained by efficient cell design and the use of nonflammable solid electrolytes, respectively. This paper presents a systematic study of experimental factors that affect the electrochemical performance of all‐solid‐state batteries. The morphological changes in composite electrodes fabricated using different mixing speeds are carefully observed, and the corresponding electrochemical performances are evaluated in symmetric cell and half‐cell configurations. We also investigate the effect of the composite electrode thickness at different charge/discharge rates for the realization of all‐solid‐state batteries with high‐energy‐density. The results of this investigation confirm a consistent relationship between the cell capacity and the ionic resistance within the composite electrodes. Finally, a concentration‐gradient composite electrode design is presented for enhanced power density in thick composite electrodes; it provides a promising route to improving the cell performance simply by composite electrode design.

Lithium metal is considered one of the most promising anode materials for realizing high volumetric and gravimetric energy density, owing to the high specific capacity (∼3860 mAh g−1) and the low electrochemical potential of lithium (−3.04 V vs. the standard hydrogen electrode). However, undesirable dendritic lithium growth and corresponding instability of the solid electrolyte interphase prevent safe and long-term use of lithium metal anodes. This paper presents a simple electrolyte approach to enhance the performance of lithium metal batteries by tuning the dielectric constant of the liquid electrolyte. Electrolyte formulations are designed by changing the concentration of ethylene carbonate to have various dielectric constants. This study confirms that high ethylene carbonate content in a liquid electrolyte enhances the cycling performance of lithium metal batteries because the electric field intensity applied to the electrolyte is reduced in relation to the polarization of the electrolyte and thus allows smooth lithium plating and formation of a stable solid electrolyte interphase. We believe that this approach provides an important concept for electrolyte system design suitable to lithium metal batteries.

The electrochemical performance of layered LiNi1-xCox/2Mnx/2O2 cathode materials (x = 2/3, 0.4, 0.2; so-called NCM333, NCM622, NCM811) in 1.0 M LiPF6-dissolved conventional carbonate-based electrolyte during formation at a 0.1 C-rate and consequent cycling at a 1.0 C-rate is measured and considered together with the results of morphology observation, impedance spectroscopy, and surface analysis. X-ray photoelectron spectroscopy (XPS) is carried out on the surface of the cathode materials before and after formation and cycling to investigate the effects of solid electrolyte interphase (SEI) formation on the electrochemical performance. As the Ni content increases, the initial specific capacity increases but the capacity retention ratio decreases. High-rate cycling overrides the SEI formation on the NCM surfaces, but NCM622 suffers great changes in the SEI components with a thick layer resulting in large interfacial resistance. It is also proved that NCM811 shows significant dissolution and accumulation of Ni species on the surface, contributing structural degradation and leading to fast capacity fading.

Organic-inorganic hybrid solid electrolytes (HSEs) are expected to overcome the inherent limitations of rigid fragile inorganic electrolytes for solid state batteries. Li-ion conductive filler such as garnet Li7La3Zr2O12 (LLZO) is proposed for the high performance of HSEs, unfortunately, which suffers from native surface layer resistance to Li-ion transport. Here we present highly conductive polyvinylidene fluoride (PVDF)-based HSEs incorporating LLZO fillers, whose resistive barriers are eliminated by dry etching. Our optimal composition of etched LLZO fillers (30 wt%) leads to ionic conductivity of 4.05 x 10-4 S cm-1, about two-fold improvement from non-etched counterpart. Li symmetric cells with etched fillers exhibit low interfacial resistance of 110 Ω cm2 and minimal overpotential of 46 mV. Moreover, high capacity of 79 mA h g-1 is highlighted at 4C, comparable or superior to liquid electrolyte or sulfide-based electrolyte devices. Interfacial environment in HSEs ideally modified for Li-ion transport is identified by 7Li NMR measurements.

All-solid-state lithium-ion batteries (ASLBs) are regarded as the next generation of energy storage devices owing to their excellent safety. However, the performance of ASLBs has yet to reach that of currently commercialized liquid electrolyte-based lithium-ion batteries due to numerous problems including the inferior ionic conductivities of solid electrolytes (SEs) and poor solid-solid interfacial contact between the SE and active material particles. Herein, dimensional control of SE particles using liquid phase synthesis is demonstrated and its favorable impact on cell performance is investigated. Argyrodite Li6PS5Cl SE with high ionic conductivity of 1.54 mS cm-1 and distinct 2D morphology was synthesized using 2D structured reduced graphene oxide as the template. The SE particles with high aspect ratio improves the long-range connectivity of the SE within the composite electrode and provides a well-connected ionic transport pathway for charge-discharge. The electrochemical impedance spectroscopy analysis of the composite electrode using electron blocking cell configuration revealed threefold enhancement of the effective ionic transport within the composite. As a result, superior rate performance was demonstrated with 2D SE composite electrodes at high C rates.

All-solid-state lithium-ion batteries (ASLBs) are receiving considerable attention due to their safety superiority and high energy density (achieved by bipolar configuration). Inorganic solid electrolytes are explored as a key-enabling material of the ASLBs. However, their critical challenges, including grain boundary resistance, interfacial instability with electrode materials and complicated processability, remain yet unresolved. Here, we demonstrate a new class of gel electrolyte with reversible thixotropic transformation and abuse tolerance as an effective and scalable approach to address the aforementioned longstanding issues. The gel electrolyte consists of (fluoropolymer/cellulose derivative) matrix and liquid electrolyte. The reversible thixotropic transformation is realized via sol-gel transition based on Coulombic interaction of the polymer matrix with liquid electrolyte. This unusual rheological feature allows the gel electrolyte to be printed in various forms. In addition, the gel electrolyte shows low crystallinity, thus playing a viable role in delivering high ionic conductivity. Based on understanding of rheological/electrochemical characteristics of the gel electrolyte, we fabricate a form factor-free pouch-type cell assembled with the gel electrolyte using sequential screen-printing process. The resultant cell shows exceptional safety upon exposure to various harsh abuse conditions, along with decent electrochemical performance.

This research was mainly supported by the Global Frontier R&D Program (2013M3A6B1078874) on Center for Hybrid Interface Materials (HIM) funded by the Ministry of Science, ICT & Future Planning, Republic of Korea, and partially supported by the Future Semiconductor Device Technology Development Program (10067739) funded by Ministry of Trade, Industry & Energy (MOTIE) and Korea Semiconductor Research Consortium (KSRC), and this study has been conducted with the support of the Korea Institute of Industrial Technology development project (KITECH EO-18-0022). The first two authors (Da-Young Kim and Jaeho Jang) contributed equally to this paper.

A facile method for preparing mesoporous perforated Co3O4 nanoparticles with hollow channels and a thin carbon layer was newly designed and achieved with sacrificial carbon nanotube (CNT) templates. The threaded Co3O4 nanoparticles on the CNTs were fabricated through a hybridization process, and a subsequent calcination process produced mesoporous perforated Co3O4 nanoparticles. With a finely tuned calcination, CNTs were sacrificed to generate hollow channels in the Co3O4 nanoparticles and to provide a carbon source for the formation of a few nm-thick carbon layer on the surface of the Co3O4 nanoparticles simultaneously. The prepared mesoporous perforated Co3O4 nanoparticles with a robust electronic conductive layer enabled not only an enhanced electrochemical reactivity from the greatly increased contact area between the electrolyte and electrode but also a high electronic conductivity of the overall electrode so that excellent electrochemical performances (1115.1 mA h g−1 after 100 cycles; 595.9 mA h g−1 @ 5 C rate) were successfully achieved in the anode application of a lithium-ion battery.

Transparent conducting electrodes (TCEs) are essential components in various optoelectronic devices. Nanostructured metallic thin film is one of the promising candidates to complement current metal oxide films, such as ITO, where high cost rare earth elements have been a longstanding issue. Herein, we present that multiscale porous metal nanomesh thin films prepared by bimodal self-assembly of block copolymer (BCP)/homopolymer blends may offer a new opportunity for TCE. This hierarchical concurrent self-assembly consists of macrophase separation between BCP and homopolymer as well as microphase separation of BCP, and thus provides a straightforward spontaneous production of a highly porous multiscale pattern over an arbitrary large area. Employing a conventional pattern transfer process, we successfully demonstrated a multiscale highly porous metallic thin film with reasonable optical transparency, electro-conductance, and large-area uniformity, taking advantage of low loss light penetration through microscale pores and significant suppression of light reflection at the nanoporous structures. This well-defined controllable bimodal self-assembly can offer valuable opportunities for many different applications, including optoelectronics, energy harvesting, and membranes.

To lower the carbon emission from the rising consumption of fossil fuels, electrochemical devices such as fuel cells and batteries, which can produce or store electricity from renewable resources, are attracting attention. Both systems require an electronically insulating solid membrane, which separates the cathode and anode to prevent short-circuiting. To improve the performance of porous electrodes, researchers have focused on tuning the electrode microstructure. The addition of highly ionic conducting materials to the electrode is commonly used to maximize the reaction site density. However, microstructural features, such as particle size distribution, electrochemically active site density and connectivity of each phase, are difficult to quantify only using conventionally used characterization methods such as scanning electron microscopy (SEM). One well-established method for obtaining three-dimensionally interconnected microstructural information is serial sectioning using a FIB/SEM dual beam system. Using this technique, more reliable and accurate quantification of the SOFC and ASSLIB electrodes microstructure are available. Also, the quantified features will be reflected in the responses of electrochemical impedance spectroscopy (EIS) measurements. These results can provide a link between them. Therefore, the aim of this study is to three-dimensionally reconstruct the microstructure of solid-state energy devices via FIB/SEM dual beam system and to quantify their microstructural features. Also, these results will be combined with the electrochemically analyzed properties to further understanding their relationship with microstructural properties.

Functional separators, which have additional functions apart from the ionic conduction and electronic insulation of conventional separators, are highly in demand to realize the development of advanced lithium ion secondary batteries with high safety, high power density, and so on. Their fabrication is simply performed by additional deposition of diverse functional materials on conventional separators. However, the hydrophobic wetting nature of conventional separators induces the polarity-dependent wetting feature of slurries. Thus, an eco-friendly coating process of water-based slurry that is highly polar is hard to realize, which restricts the use of various functional materials dispersible in the polar solvent. This paper presents a surface modification of conventional separators that uses a solution-based coating of graphene oxide with a hydrophilic group. The simple method enables the large-scale tuning of surface wetting properties by altering the morphology and the surface polarity of conventional separators, without significant degradation of lithium ion transport. On the surface modified separator, superior wetting properties are realized and a functional separator, applicable to lithium metal secondary batteries, is demonstrated as an example. We believe that this simple surface modification using graphene oxide contributes to successful fabrication of various functional separators that are suitable for advanced secondary batteries.

Here, we demonstrate a novel synthetic route to prepare restacked nanohybrid graphene layers (NHGLs) with the expanded interlayer distance enabled by incorporating inorganic spacer for the reliable high-capacity sodium-ion battery (NIB) anodes. Nanohybrid graphene oxide flakes (NHGOFs) were obtained through partial complexation of metallic Sn cation with graphene oxides (GOs) exfoliated from graphite. Negatively charged NHGOFs were restacked parallel to Zn substrate through an electrostatic interaction with Zn in an acidic solution. After detachment and freeze-drying step, NHGLs with the expanded interlayer distance of ~ 7.54 A along the c-axis supported by metallic Sn cation spacer were achieved. To clarify the beneficial effect of the expanded interlayer distance, electrochemical performances of NHGLs anode were investigated. Finally, a flexible feature of restacked NHGLs anode was presented during a simple bending test using a pouch-type cell.

The surface area of the lithium metal electrode must be considered when attempting to suppress dendritic growth of lithium metal, as surface area can lower the effective current density. For this reason, lithium metal powder (LiMP) has attracted much attention for use in electrodes because of its higher surface area. However, repeated cycling, even in aging time, leads to delamination of lithium particles from flat metal current collectors and results excess dead lithium particles, even in LiMP electrodes. Herein, this problem is addressed by coating submicron-thickness carbon interlayers on copper current collectors for LiMP electrodes. This thin carbon layer plays important roles in both maintaining the interfacial contact between Cu foil and LiMP particles and lowering overpotential in Li/Li symmetric cells, which leads to improve electrochemical performance in thin LiMP (40 μm) based cell. These enhancements are related to the enlarged surface area, as confirmed by higher adhesion of the electrode after precycling. Furthermore, the carbon materials are also believed to contribute to seeding for efficient lithium nucleation. Thus, thin carbon layers on current collectors can provide simple but powerful enhancements to the electrochemical performance of high-energy-density LMSBs.

Solid oxides are attractive electrolyte materials for all-solid-state lithium batteries (ASSLBs) owing to their high stability and pure Li-ion conductivity. Nevertheless, the electrochemical performance of ASSLBs employing solid oxide-based electrolytes cannot compete with ASSLBs with sulfide or polymeric electrolytes due to poor interfacial contact and high boundary resistance between the active materials and solid oxide electrolytes. To overcome this hurdle, elaborate microstructural analysis of the interface of the active material/solid oxide electrolyte in ASSLBs is essentially required since the interfacial contact area dominantly acts as the ion pathway and the electrochemical reaction site in the electrode. Although recent attempts on interfacial structure analysis of ASSLBs have provided simple 2D or semi-3D microstructural features, the results have not yielded deep insights. Herein, we investigated the interfacial defects in an all-solid-state electrode with a solid oxide electrolyte via a 3D digital twin technology combining 3D structural quantification and physico-electrochemical simulations to unravel the intrinsic limitations of solid oxide electrolytes. The in-depth results can be used to design materials and optimize electrode design parameters for ASSLBs.

Layered electrodes of electrodeposited RuO 2 (eRuO 2 ) and polyaniline (ePAn) are prepared on a platinum substrate to yield ePAn-on-eRuO 2 and eRuO 2 -on-ePAn electrodes and their supercapacitive properties are investigated. The eRuO 2 electrode forms a compact stratified structure with nearly flat surfaces by electrodeposition from a RuCl 3 ·3H 2 O-based solution, whereas the ePAn electrode forms densely connected particles or particle aggregates by the electrodeposition from aniline solution. In the scan rate range of 20–1000 mV s −1 , specific capacitance (810–575 F g −1 ) of ePAn-on-eRuO 2 electrode is superior by the higher probability to occur redox reaction and proton diffusion due to particulate surface and inner pores of the upper layer (ePAn), respectively. In contrast, the eRuO 2 -on-ePAn electrode loses the specific capacity (680–550 F g −1 ) but achieves higher capacity retention ratio (81%) by flat compact surface of the upper layer (eRuO 2 ).

To enhance the electrochemical performance, a conventional activated carbon supercapacitor is modified by adopting potassium-polyacrylate (PAAK) electrolyte additive on a glass fiber separator and by fabricating the activated carbon electrode on nickel foam instead of on conventional nickel foil as a current collector. The glass fiber separator plays the role of self-supporting PAAK-KOH hydrogel electrolyte with superior ionic conductivity. Moreover, the adoption of nickel foam strengthens the close contact between the active material and the current collector, reducing the interfacial resistance between electrode and electrolyte. As a result, the combination of glass fiber separator and nickel foam substrate can contribute to a great increase in the specific capacitance, to a value of over 200 F g−1, and to an enhancement of the high-rate capability of activated carbon supercapacitors.

All-solid-state lithium secondary batteries have never shown both higher energy and power density than them of conventional lithium-ion batteries. Herein, on the basic of well-established percolation theory, we expected what includes a dimension-controlled solid electrolyte in an electrode can improve the electrochemical properties, such as ionic conduction and capacity retention. The behavior of electrodes is systematically demonstrated via computational simulations of virtual electrodes with various dimension-controlled solid electrolytes. In particular, the effective ionic conductivity and the specific contact area are investigated as key parameters that determine cell performance. We confirmed that the dimension-controlled solid electrolyte can improve the electrochemical performance of all-solid-state batteries by enhancing the effective ionic conductivity, which is facilely realized via percolation of the solid electrolyte with an increased dimensional geometry. This simulation prediction suggests a clue to be able to overcome poor performance of present all-solid-state batteries.

Li1+xAlxTi2-x(PO4)3 (LATP) solid electrolytes are prepared by hydrothermal reaction as an effective method to yield moderate ionic conductivity adoptable in actual lithium-ion batteries. Particularly examined in this study are the effects of the synthesis conditions, such as Al dopant concentration (x), hydrothermal reaction time, and calcination and sintering temperatures, on the ionic conductivity of the synthesized LATP. Through repeated synthesis and characterizations of the LATPs by variation of the values of condition variables, the optimum condition for the best LATP with adequate ionic conductivity applicable to actual lithium batteries are determined to be x = 0.3 or 0.4, a hydrothermal reaction time of 12 h, and calcination and sintering temperatures of 600 °C and 900 °C, respectively.

A facile direct hybridization route to prepare SnO2/graphene nanocomposites for Li-ion battery anode application is demonstrated. Uniform distribution of SnO2 nanoparticles on graphene layers was enabled by a one-step chemical synthetic route. The optimal content ratio of SnO2 and graphene was determined from microscopic observations and electrochemical studies. The nanocomposite anode with SnO2 loading level of around 70 wt.% retained reversible capacity of 643.6 mAh/g after 50 cycles and high discharge capacity of 347.8 mAh/g at a current density of 3000 mA/g, which was superior to that of graphene-only electrodes or nanocomposites with overloaded SnO2 nanoparticles. Taking advantage of nano-sized SnO2 and an electrically conductive and mechanically flexible graphene layer, SnO2/graphene nanocomposites with optimized SnO2 content exhibit excellent electrochemical properties as lithium-ion battery anodes. Our strategy offers a straightforward and high-throughput pathway for creating and directing graphene-based functional hybrids through simple mixing and thermal treatments, and may be used to assemble high-performance Li-ion batteries.

For use as an anode material in lithium batteries, composites consisting of TiO2 nanotubes (TNTs) and carbon nanotubes (CNTs) are prepared by combining hydrothermal reaction of rutile TiO2 bulk particles, blending with different amounts (0–30 wt.%) of CNTs, ball-milling, and subsequent heat treatment at 300 °C. Crystalline property analysis and morphology observation of the prepared TNT-CNT powders prove that at low CNT content the composites are consisted of dominant phase of aggregated anatase TNTs. The TNT aggregates are relaxed with increased CNT content to form crosslinked networks surrounding the amorphous CNT phases that act as a dispersing matrix. As a result, the TNT-CNT composite anode with CNT (30 wt.%) is superior for application in lithium-ion batteries because it shows a saturated discharge capacity after about 20th cycle, good high-rate capability, and the lowest interfacial resistance of 1.7–2 Ω cm−2. The superior anode properties of TNT-CNT composite with high content of CNT are mainly due to CNT’s functions to enhance electron transfer and to facilitate Li+ diffusion by dispersing the TNT agglomeration.

High-resolution (10 nm), high-areal density, high-aspect ratio (>5), and morphologically complex nanopatterns are fabricated from a single conventional block copolymer (BCP) structure with a 70 nm scale resolution and an aspect ratio of 1, through the secondary-sputtering phenomenon during the Ar-ion-bombardment process. This approach provides a foundation for the design of new routes to BCP lithography.

Context In applying good energy conservation strategies to relieve cancer-related fatigue, it is critical to first identify cancer patients who are at a high risk for poor energy conservation. However, instruments have not been developed to evaluate energy conservation strategies in an oncology setting. Objectives The aim of this study was to validate an instrument that cancer patients may use to evaluate energy conservation strategies to overcome cancer-related fatigue. Methods The questionnaire development followed a four-phase process: 1) item generation and reduction, 2) construction, 3) pilot testing, and 4) field testing. Using relevant and priority criteria, as well as pilot testing, we developed a 25-item questionnaire. After field testing, five items were discarded. Finally, 20 items were included in the Energy Conservation Strategies Inventory (ECSI). Factor analysis, multitrait scaling analysis, and Cronbach's α were used to determine the construct validity and reliability. Results Factor analyses of data from 140 cancer patients resulted in the ECSI, which covers activities related to planning, overcoming distractions, labor saving, burden reducing, and comfort. All subscales (Cronbach's α range, 0.69–0.78) and total scores (Cronbach's α=0.87) were found to possess acceptable internal consistency. Conclusions The good psychometric properties of the ECSI instrument show that it may be useful for measuring the frequency of energy conservation strategies used by cancer patients.

thus far.Here we demonstrate that chemically modified grapheneis an excellent substrate material for adsorption and also forspatial patterning of DNA origami structures. Our strategy isto integrate the top-down patterning of chemically modifiedgraphene through conventional photolithography withbottom-up self-assembly of DNA origami structures uponthe patterned chemically modified graphene. Because of thesmoothness at atomic scale and chemical diversity of chemi-cally modified graphene, including GO, reduced grapheneoxide (rGO), and nitrogen-doped reduced graphene oxide(NrGO), the adsorption of DNA origami structures can besystematically tuned to allow spatial patterning on chemicallymodified graphene.Figure 1 illustrates the procedure for patterning of DNAorigami structures. A GO film was spin-cast from aqueoussolution onto an NH

solar cells, [ 4 ] and photonic crystals, [ 5 ] 2D hexagonal structures and 3D inverted opal (IO) structures have recently been intensively studied. In order to fabricate uniform IO structures consisting of regular arrangements of spherical void spaces surrounded by solid walls, 2D and 3D colloidal crystals consisting of a regular arrangement of uniform spherical particles are required. To date, a number of techniques to assemble colloidal particles into 2D and 3D opals have been developed: 3D colloidal crystals have been fabricated by sedimentation, [ 6 ] convective assembly, [ 7 ] and electrophoretic deposition, [ 8 ] while 2D colloidal crystals are produced by confi ned convective assembly. [ 9 ] Generally, 2D colloidal crystals have been used to fabricate 2D structures through edge spreading lithography, [ 10 ] colloidal masking, and templating while 3D colloidal crystals have been independently utilized to construct 3D structures through infi ltration and templating. [ 11 , 12 ]