Droplet microfluidics technology is recently a highly interesting platform in material fabrication. Droplets can precisely monitor and control entire material fabrication processes and are superior to conventional bulk techniques. Droplet production is controlled by regulating the channel geometry and flow rates of each fluid. The micro-scale size of droplets results in rapid heat and mass-transfer rates. When used as templates, droplets can be used to develop reproducible and scalable microparticles with tailored sizes, shapes and morphologies, which are difficult to obtain using traditional bulk methods. This technology can revolutionize material processing and application platforms. Generally, microparticle preparation methods involve three steps: (1) the formation of micro-droplets using a microfluidics generator; (2) shaping the droplets in micro-channels; and (3) solidifying the droplets to form microparticles. This review discusses the production of microparticles produced by droplet microfluidics according to their morphological categories, which generally determine their physicochemical properties and applications.

N-doped graphene grafted hollow TiO₂ nanostructures were fabricated and evaluated as a promising candidate for sodium storage.

2D porous carbon nanosheets (PCNs) occupy the foreground in the field of electric double-layer capacitors (EDLCs). However, the mass production of PCNs with ultrathin thicknesses is still a serious challenge. Herein, PCNs constructed of few-layer graphene sheets were synthesized from a sulfonated pitch (SP) carbon precursor and soft-template F127 by a “medium-up” strategy. SP serves as a “medium material”, while F127 acts as a “string” and “spacer”, which plays the leading role of structure directing and prevents the self-restacking of small graphene layers. After activation, sample PCN6 with high carbon yield is constructed with a thickness of only 1.3 nm, sufficient specific surface area of 3006 m² g⁻¹ and high e-conductivity of 135 S m⁻¹. By virtue of its unique architecture, the PCN6-based EDLC exhibits excellent energy storage properties. In EMIMBF₄ electrolyte, it demonstrates an ultrahigh C_g of 157.8 F g⁻¹ (57.4 F cm⁻³) at 20 A g⁻¹, possessing a top-level rate capacity C_20/0.05 of 86.7%. Simultaneously, its energy density can retain up to 67.1 W h kg⁻¹ at a high power density of 17.5 kW kg⁻¹. The ingenious structural design of PCNs can afford inspiration for constructing other 2D architecture carbon materials.