Nanocrystal Inks: Photoelectrochemical Printing of Cu₂O Nanocrystals on Silicon with 2D Control on Polyhedral Shapes

Abstract

text. Here is reported a printing technology that enables the functionalization of photoconducting materials with an arbitrary user-defined pattern of nanocrystals. Two sets of information can be encoded into the same unit area; control over the polyhedral shape of individual nanocrystals and high lateral resolution (micrometre scale) for large 2D patterns (millimetre scale) of Cu2O that were grown over unstructured amorphous silicon. Key to this new technology is a parallel modulation of both the electrode kinetics at the silicon/electrolyte interface as well as the light-assisted control of adsorption of halide ions on the growing Cu2O particles. This is achieved using local pixelation of a visible light stimuli by means of adapting to the field of photoelectrochemistry the instrumental tools for spatial light modulation more often used in super resolution microscopy. Any user-defined pattern (i.e., any arbitrary bitmap image file or a sequence of images) is converted within seconds into an array of nanoparticles. The process does not rely on the use of physical masks Received: ((will be filled in by the editorial staff)) Revised: ((will be filled in by the editorial staff))

Surface Patterning of Biomolecules Using Click Chemistry and Light‐Activated Electrochemistry to Locally Generate Cu(I)

“…Light activated electrochemistry (LAE) is a technique capable of spatially resolving faradaic electrochemistry with a focused light beam illuminated on an unpatterned semiconductor electrode surface [10] . The addressability of light to confine electrochemistry at multiple regions of the electrode without perturbing the electrolyte solution (i.e hydrodynamic forces) makes LAE ideal for electrodepositing multiple metals, [11] oxides [12] and polymers, [10] selectively releasing captured single circulating tumour cells, [13] and locally monitoring extracellular potassium on drug stimulated cells [14] . However, the technique has not been utilized for the localized bioconjugation yet.…”

“…As shown in Figure 2 b and d, bicinchoninic acid forms a complex with Cu(I) to generate the colorimetric adduct (Abs=562 nm) only in presence of light. This result also confirms that in the dark there is no electrochemical communication between Cu 2+ in solution and the bulk pSi (100) due to the 1 μm thick a‐Si, consistent with our previous report [12] . To stabilise Cu(I) and avoid formation of Cu (0), a copper stabilizing ligand, tris (2‐pyridylmethyl) amine was employed.…”

Chemically modified nanofoci unifying plasmonics and catalysis

“…[29][30][31] A method based on combined optical-electrochemical processes has been reported for in situ growth of NP patterns. 43,44 However, it is difficult to achieve spacing control with nanometer accuracy. We developed a facile and highly efficient Ag ion soldering (AIS) strategy to make subnm-gapped nanofoci.…”

Light in Electrochemistry

“…In addition, a ferrocene-containing azide group was introduced onto the surface via a copper-catalyzed azide-alkyne cycloaddition reaction to accelerate the redox reaction at the interface. Ciampi's group recently reported the microfabrication of Cu 2 O silicon [83,84], for the imaging of methanol oxidation upon electrocatalysis (Figure 5a) [85].…”