Facile method for 3D printing conformally onto uneven surfaces and its application to face masks.

Conventional additive manufacturing processes, where parts are built through layer-wise deposition of material on a horizontal plane, can be limiting when a part must be printed or fit onto uneven surfaces. Such situations will arise with increasing frequency as additive manufacturing application areas such as construction and medical devices continue to grow. In this work, we develop a simple and practical approach to generate toolpaths to print 3D structures onto uneven surfaces conformally.

Generalisable 3D printing error detection and correction via multi-head neural networks.

Material extrusion is the most widespread additive manufacturing method but its application in end-use products is limited by vulnerability to errors. Humans can detect errors but cannot provide continuous monitoring or real-time correction. Existing automated approaches are not generalisable across different parts, materials, and printing systems.

Real-Time Imaging of Self-Organization and Mechanical Competition in Carbon Nanotube Forest Growth.

The properties of carbon nanotube (CNT) networks and analogous materials comprising filamentary nanostructures are governed by the intrinsic filament properties and their hierarchical organization and interconnection. As a result, direct knowledge of the collective dynamics of CNT synthesis and self-organization is essential to engineering improved CNT materials for applications such as membranes and thermal interfaces. Here, we use real-time environmental transmission electron microscopy (E-TEM) to observe nucleation and self-organization of CNTs into vertically aligned forests.

High-speed roll-to-roll manufacturing of graphene using a concentric tube CVD reactor.

We present the design of a concentric tube (CT) reactor for roll-to-roll chemical vapor deposition (CVD) on flexible substrates, and its application to continuous production of graphene on copper foil. In the CTCVD reactor, the thin foil substrate is helically wrapped around the inner tube, and translates through the gap between the concentric tubes. We use a bench-scale prototype machine to synthesize graphene on copper substrates at translation speeds varying from 25 mm/min to 500 mm/min, and investigate the influence of process parameters on the uniformity and coverage of graphene on a continuously moving foil.

Crystal engineering of zeolites with graphene.

Achieving control over the morphology of zeolite crystals at the nanoscale is crucial for enhancing their performance in diverse applications including catalysis, sensors and separation. The complexity and sensitivity of zeolite synthesis processes, however, often make such control both highly empirical and difficult to implement. We demonstrate that graphene can significantly alter the morphology of titanium silicalite (TS-1) particles, in particular being able to reduce their dimensions from several hundreds to less than 10 nm.

En route to controlled catalytic CVD synthesis of densely packed and vertically aligned nitrogen-doped carbon nanotube arrays.

The catalytic chemical vapour deposition (c-CVD) technique was applied in the synthesis of vertically aligned arrays of nitrogen-doped carbon nanotubes (N-CNTs). A mixture of toluene (main carbon source), pyrazine (1,4-diazine, nitrogen source) and ferrocene (catalyst precursor) was used as the injection feedstock. To optimize conditions for growing the most dense and aligned N-CNT arrays, we investigated the influence of key parameters, i.

Nitrogen-induced catalyst restructuring for epitaxial growth of multiwalled carbon nanotubes.

The ability to simply and economically produce carbon nanotubes (CNTs) with a defined chiral angle is crucial for the exploitation of nanotubes for their electrical properties. We investigate a diverse range of nitrogen sources for their ability to control CNT chiral angle via epitaxial growth from highly ordered catalyst particles. Through the use of in situ mass and infrared spectrometry, we elucidate the mechanism by which these ordered catalyst particles are formed, showing that ammonia is a key intermediate in the process.

Enhanced photocatalytic properties in well-ordered mesoporous WO3.

We used polyisoprene-block-ethyleneoxide copolymers as structure-directing agents to synthesise well-ordered and highly-crystalline mesoporous WO(3) architectures that possess improved photocatalytic properties due to enhanced dye-adsorption in absence of diffusion limitation.