Amino-substituted spirothiopyran as an initiator for self-assembly of gold nanoparticles

Shiraishi, Yasuhiro; Tanaka, Haruki; Sakamoto, H.; Ichikawa, Satoshi; Hirai, Takayuki

doi:10.1039/c5ra14752b

Cited by 2 publications

(2 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…35 This suggests that AuNPs formed by thermal reduction of HAuCl 4 are subsequently aggregated. 21,36 It is noted that the obtained solution maintain its transparency at least 2 days, where a precipitate formation scarcely occurs. Fig.…”

Section: Thermal Reductionmentioning

confidence: 87%

Photoreductive synthesis of monodispersed Au nanoparticles with citric acid as reductant and surface stabilizing reagent

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

Section: Thermal Reductionmentioning

confidence: 87%

Photoreductive synthesis of monodispersed Au nanoparticles with citric acid as reductant and surface stabilizing reagent

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…In this paper, we demonstrate monolayers of the sulfur-containing analogue, spirothiopyran (STP), a molecule that has attracted recent attention, − as a viable alternative for direct writing. The MC isomer of STP can participate in a thiol-Michael addition with α, β unsaturated carbonyl compounds to form a nonswitchable Michael addition product (MAP), which serves as the desired written state.…”

Section: Introductionmentioning

confidence: 99%

Effect of Chemical Microenvironment in Spirothiopyran Monolayer Direct-Write Photoresists

et al. 2019

View full text Add to dashboard Cite

We study the effect of the microenvironment on writing chemical patterns into spirothiopyran monolayers over large areas in a single step with light. Surfaces functionalized with photoresponsive spirothiopyran are fabricated by chemically modifying amine-terminated monolayers. The merocyanine isomer selectively participates in a thiol-Michael addition reaction with maleimide-functionalized molecules, rendering these surfaces ideal for fast, mask-less direct writing. The local microenvironment of spirothiopyran is found to strongly influence the kinetics of photoswitching. The quantum yield of ring opening is found to be 17 times faster for spirothiopyran surrounded by a locally charged environment rich in guanidinium diluent molecules as compared to a closed-packed monolayer without diluents. Hydrophilic environments are also found to improve the kinetics of ring closing. Optimization of the diluent concentration leads to dramatic improvements in both contrast and yield of direct writing. This enables the monolayer to be used for maskless two-color photopatterning in which spatial control over patterning is obtained by varying the relative intensity of incident UV and green light. These experiments demonstrate the capacity of spirothiopyran monolayers to serve as a versatile toolbox for rapid, large-area surface functionalization.

show abstract

Amino-substituted spirothiopyran as an initiator for self-assembly of gold nanoparticles

Abstract: Amino-substituted spirothiopyran promotes spontaneous aggregation of gold nanoparticles, producing the aggregates with tunable sizes and narrow size distributions.

Cited by 2 publications

References 52 publications

Photoreductive synthesis of monodispersed Au nanoparticles with citric acid as reductant and surface stabilizing reagent

Photoreductive synthesis of monodispersed Au nanoparticles with citric acid as reductant and surface stabilizing reagent

Effect of Chemical Microenvironment in Spirothiopyran Monolayer Direct-Write Photoresists

Contact Info

Product

Resources

About