A photocatalytic approach was used to synthesize triangular nanoplates in aqueous solution. The synthesis is based on the reduction of a gold salt using a tin(IV) porphyrin as photocatalyst, cetyltrimethylammonium bromide (CTAB) as a stabilizing agent, and triethanolamine (TEA) as the final electron donor. The average edge length of the triangular nanoplates can be easily changed in the range 45–250 nm by varying the concentration of photocatalyst, and fine-tuning of the average edge length is achieved by varying the concentration of CTAB. Study of the mechanism of formation of the nanoplates by UV-vis and by transmission electron microscopy (TEM) shows that there is a first stage where formation of 5 nm seeds takes place, further growth is probably by fusion and by direct reduction of gold onto the preformed nanoparticles. The nanoparticles formed during the photocatalytic reduction of the gold precursor show an irregular shape that evolves to regular triangular nanoplates after ripening in solution for 24 h.

Stable Au and Ag nanoparticles with diameter 5–10 nanometers were synthesized in water at pH 7 and at room temperature by a novel green photocatalytic method. The method features very low energy consumption and non-toxic reagents with high yields of concentrated nanoparticles in aqueous solution obtained in less than four minutes. The nanoparticles so obtained are highly monodispersed, thus avoiding the use of further time consuming and cumbersome purification procedures. In addition, the capping agent is readily exchanged by thiols, providing a facile way of functionalization for biological applications.

(3-aminopropyl)triethoxysilane (APTES) is a commonly used organosilane on surface functionalization of silicon oxide surfaces. However, its deposition process from solution-phase usually involves the use of toluene, which has often been identified as crucial for the formation of an aminopropylsilane monolayer. Toluene is ranked as a problematic solvent in the guide developed by a group referred to as the solvent sub-team of CHEM21. In this work, we propose a facile synthetic route for functionalizing a silicon substrate with APTES via solution-phase approach using only solvents that are classified as recommended. The influence of the APTES concentration, reaction times and different post-deposition conditions using acetic acid and methanol were studied in order to evaluate the quality and thickness of the organosilane layers.•The method uses ethanol as APTES solvent for functionalizing silicon dioxide surfaces and only uses solvents classified as recommended.•The method uses a solution phase approach, does not require complicated equipment and can be prepared at room temperature.

This review provides a detailed picture of the innovative efforts to combine atomic force microscopy and different super-resolution microscopy techniques to elucidate biological questions.