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Colloidal crystals are interesting materials owing to their customizable photonic properties, high surface area, and analogy to chemical structures. The flexibility of these materials has been greatly enhanced through mixing particles with varying sizes, compositions, and surface charges. In this way, distinctive patterns or analogies to chemical stoichiometries are produced; however, to date, this body of research is limited to particles with nanoscale dimensions. A simple method is now presented for bottom-up assembly of non-Brownian particle mixtures to create a new class of hierarchically-ordered materials that mimic those found in nature (both in pore distribution as well as stoichiometry). Additionally, these crystals serve as a template to create particle-based inverted crystalline structures with customizable properties.

Non-Brownian microparticle mixtures are assembled into unique multicomponent colloidal crystals and their inverse structures. By mimicking the effects of Brownian motion through agitation and tuning of the particle sizes and volume ratios, unique stoichiometric patterns are created and can serve as an analogue to autonomously formed nanostructures.

A new theranostic platform is developed based on biocompatible poly(acrylic acid) (PAA)-Co₉ Se₈ nanoplates. These PAA-Co₉ Se₈ nanoplates are successfully utilized for photoacoustic imaging (PAI)/magnetic resonance imaging (MRI) dual-modal imaging. Moreover, the PAA-Co₉ Se₈-DOX shows pH-responsive chemotherapy and enables the combination of photothermal therapy and chemotherapy to receive superior antitumor efficacy. This work promises further exploration of 2D nanoplatforms for theranostic applications.

Controllable bandgap widening from 1.8 to 2.6 eV is reported from oxidized MoS₂ sheets that are composed of quilted phases of various MoS_xO_y flakes. The exfoliated flakes have large size (≥100 μm × 100 μm) sheets with average thickness of 1.7 nm. Remarkably, fine reversible tuning of the bandgap is achieved by postprocessing sulfurization of the MoS_xO_y sheets.

While great progress has been achieved in the synthesis of ordered mesoporous carbons in the past decade, it still remains a challenge to prepare highly graphitic frameworks with ordered mesoporosity and high surface area. Reported herein is a simple synthetic methodology, based on the conversion of self-assembled superlattices of Fe₃O₄ nanocrystals, to fabricate highly ordered mesoporous graphene frameworks (MGFs) with ultrathin pore walls consisting of three to six stacking graphene layers. The MGFs possess face-centered-cubic symmetry with interconnected mesoporosity, tunable pore width, and high surface area. Because of their unique architectures and superior structural durability, the MGFs exhibit excellent cycling stability and rate performance when used as anode materials for lithium-ion batteries, thus retaining a specific capacity of 520 mAh g⁻¹ at a current density of 300 mA g⁻¹ after 400 cycles.

Framed: The title frameworks were fabricated from self-assembled Fe₃O₄ nanocrystal superlattices. Because of their unique architectures and superior structure durability, the mesoporous graphene frameworks exhibit excellent electrochemical performance when used as anode materials for lithium-ion batteries.

ZSM-5 hollow crystals are functionalized with multiple catalytic sites, the structure of which resembles a cell-like structure on the nanometer scale. The crystal size of the nanoreactor is below 100 nm. The material is functionalized with metal oxide particles within the hollow or on the external crystal surface. Additionally, Brønsted acid sites are present in the zeolite channels.

On page 2298, D. Liu, H. A. Santos, and co-workers demonstrate nanoparticles with controlled quality and high throughput that are generated from a microcapillary device using a microfluidic nanoprecipitation approach. The successful preparation of a variety of nanoparticles demonstrates the versatility of this platform. Independently of the formulation parameters, nanoparticles with homogeneous size distribution can always be obtained, showing the great robustness of this platform.

Liquid metal nanoparticles that may be mechanically sintered are demonstrated by R. K. Kramer and co-workers on page 2355. Dispersing the nanoparticles in a carrier solvent results in an ink-jettable solution, allowing for scalable and high-throughput manufacturing of soft conductive systems. One potential application for this processing technology is wearable electronics, as depicted by the data glove featured in the cover art. Artistic rendition created by Mr. Alex Bottiglio.