Now showing1 - 8 of 8
  • Some of the metrics are blocked by your 
    Item type:Publication, Access status: with files ,
    Enhancing interfacial charge transport in Gold Nanoparticle@Polyaniline hybrids via N-heterocyclic carbene linkers
    (Wiley-VCH, 2026-05-11) ; ; ; ;
    N-Heterocyclic carbenes (NHCs) have emerged as a unique class of ligands for gold nanoparticles (Au NPs), combining strong metal binding with intrinsic electronic conductivity. Yet over the past decade, studies on Au NP@NHC systems have primarily focused on their stability, while the conductivity of NHCs has remained largely unexplored due to synthesis challenges. Here, we present a synthetic strategy that addresses this gap by employing amino-functionalized NHC-Au complexes with in situ oxidative polymerization of polyaniline (PANI) to yield electronically coupled Au NP@NHC-PANI hybrids in aqueous media. This strategy enables both a controlled PANI shell growth and introduction of an electronically active NHC interlayer. Single-particle scattering spectroscopy reveals that NHCs improve the interfacial electronic coupling as evidenced by pronounced plasmonic linewidth broadening. Conductivity measurements further confirm that NHCs enhance charge transport: conductive atomic force microscopy (C-AFM) shows an increase in contact current from 14.6 to 99.4 pA under a 300-mV bias, while lateral four-probe conductance increases from 0.17 to 3.5 nS. These results provide the first direct experimental evidence of the conductive role of NHCs in hybrid NP-polymer systems, establishing a new interface-engineering strategy for the rational design of electronically delocalized nanostructures and their applications in nanoelectronics.
    Publicationtype: Journal Article
      58  13
  • Some of the metrics are blocked by your 
    Item type:Publication, Access status: with files ,
    Efficient and reversible chirality induction between protein and achiral plasmonic assemblies
    (Nature Publishing Group, 2026-04-15) ; ; ; ;
    Chiral molecules in nature usually show optical activity only in the deep ultraviolet, whereas artificial chiral plasmonic nanostructures can generate much stronger responses at visible and near-infrared wavelengths. An important challenge is whether the abundant biomolecular chirality in nature can be directly transferred to achiral plasmonic systems without elaborate three-dimensional nanofabrication. Here we show that the mechanical stretching of protein molecules anchored within achiral gold nanoparticle assemblies strongly enhances and reversibly modulates plasmon-coupled circular dichroism. Stretching amplifies the chiroptical response to an ellipticity of 1.18° and a dissymmetry factor of 0.2, far exceeding conventional hotspot-based strategies. Repeated stretching and relaxation further enable reversible switching over more than 100 cycles. Simulations and in situ spectroscopy indicate that the deformation of protein changes its conformation and dipole alignment, thereby strengthening the plasmonic chiral response. These findings establish a route to achieve dynamically controllable chiroptical activity in achiral plasmonic assemblies, revealing how small biomolecular deformations can strongly influence plasmonic responses of much larger nanostructures.
    Publicationtype: Journal Article
      21  24
  • Some of the metrics are blocked by your 
    Item type:Publication, Access status: with files ,
    Gold Nanoparticles with N-Heterocyclic Carbene/Triphenylamine Surface Ligands: Stable and Electrochromically Active Hybrid Materials for Optoelectronics
    (Wiley, 2024-08-07) ;
    Singh, Shivam
    ;
    Zhang, Haoran
    ;
    ;
    Organic-hybrid particle-based materials are increasingly important in (opto)electronics, sensing, and catalysis due to their printability and stretchability as well as their potential for unique synergistic functional effects. However, these functional properties are often limited due to poor electronic coupling between the organic shell and the nanoparticle. N-heterocyclic carbenes (NHCs) belong to the most promising anchors to achieve electronic delocalization across the interface, as they form robust and highly conductive bonds with metals and offer a plethora of functionalization possibilities. Despite the outstanding potential of the conductive NHC-metal bond, synthetic challenges have so far limited its application to the improvement of colloidal stabilities, disregarding the potential of the conductive anchor. Here, NHC anchors are used to modify redox-active gold nanoparticles (AuNPs) with conjugated triphenylamines (TPA). The resulting AuNPs exhibit excellent thermal and redox stability benefiting from the robust NHC-gold bond. As electrochromic materials, the hybrid materials show pronounced color changes from red to dark green, a highly stable cycling stability (1000 cycles), and a fast response speed (5.6 s/2.1 s). Furthermore, TPA-NHC@AuNP exhibits an ionization potential of 5.3 eV and a distinct out-of-plane conductivity, making them a promising candidate for application as hole transport layers in optoelectronic devices.
    Publicationtype: Journal Article
      27  32
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Poly(3-hexylthiophene)s Functionalized with N-Heterocyclic Carbenes as Robust and Conductive Ligands for the Stabilization of Gold Nanoparticles
    Recently, N-heterocyclic carbenes (NHCs) are explored as anchor groups to bind organic ligands to colloidal gold (i.e. gold nanoparticles, Au NPs), yet these efforts are confined to non-conjugated ligands so far—that is, focused solely on exploiting the stability aspect. Using NHCs to link Au NPs and electronically active organic components, for example, conjugated polymers (CPs), will allow capitalizing on both the stability as well as the inherent conductivity of the NHC anchors. Here, we report three types of Br-NHC-Au-X (X=Cl, Br) complexes, which, when used as starting points for Kumada polymerizations, yield regioregular poly(3-hexylthiophenes)-NHC-Au (P3HTs-NHC-Au) with narrow molecular weight distributions. The corresponding NPs are obtained via direct reduction and show excellent thermal as well as redox stability. The NHC anchors enable electron delocalization over the gold/CP interface, resulting in an improved electrochromic response behavior in comparison with P3HT-NHC-Au.
    Publicationtype: Journal Article
    Scopus© Citations 19  18
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Ultrasoft and High-Mobility Block Copolymers for Skin-Compatible Electronics
    Polymer semiconductors (PSCs) are an essential component of organic field-effect transistors (OFETs), but their potential for stretchable electronics is limited by their brittleness and failure susceptibility upon strain. Herein, a covalent connection of two state-of-the-art polymers—semiconducting poly-diketo-pyrrolopyrrole-thienothiophene (PDPP-TT) and elastomeric poly(dimethylsiloxane) (PDMS)—in a single triblock copolymer (TBC) chain is reported, which enables high charge carrier mobility and low modulus in one system. Three TBCs containing up to 65 wt% PDMS were obtained, and the TBC with 65 wt% PDMS content exhibits mobilities up to 0.1 cm2 V−1 s−1, in the range of the fully conjugated reference polymer PDPP-TT (0.7 cm2 V−1 s−1). The TBC is ultrasoft with a low elastic modulus (5 MPa) in the range of mammalian tissue. The TBC exhibits an excellent stretchability and extraordinary durability, fully maintaining the initial electric conductivity in a doped state after 1500 cycles to 50% strain.
    Publicationtype: Journal Article
    Scopus© Citations 50  22
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Prospects of Coupled Organic–Inorganic Nanostructures for Charge and Energy Transfer Applications
    We review the field of organic–inorganic nanocomposites with a focus on materials that exhibit a significant degree of electronic coupling across the hybrid interface. These nanocomposites undergo a variety of charge and energy transfer processes, enabling optoelectronic applications in devices which exploit singlet fission, triplet energy harvesting, photon upconversion or hot charge carrier transfer. We discuss the physical chemistry of the most common organic and inorganic components. Based on those we derive synthesis and assembly strategies and design criteria on material and device level with a focus on photovoltaics, spin memories or optical upconverters. We conclude that future research in the field should be directed towards an improved understanding of the binding motif and molecular orientation at the hybrid interface.
    Publicationtype: Journal Article
    Scopus© Citations 42  15
  • Some of the metrics are blocked by your 
    Item type:Publication,
    “Colorless-to-black” electrochromic and AIE-active polyamides: An effective strategy for the highest-contrast electrofluorochromism
    Electrofluorochromic (EFC) materials have gained extensive attention owing to their interesting modulations of fluorescence by an electric stimulus. However, the limited performances, especially the low fluorescence on/off contrast, significantly hampered their further applications. Herein, we design a new strategy to achieve high-contrast electrofluorochromism by combinations of “colorless-to-black” electrochromism and highly fluorescent AIE activity. Given the effective fluorescence quenching effect and high solid-state fluorescence, a fluorescence contrast of 838 is realized, to the best of our knowledge, the highest reported so far. Furthermore, to explore the structure-property relationships, we also separated the E/Z isomers of tetraphenylethylene (TPE) and studied the properties of the three electroactive/fluorescent polymers (11TPE-PA, E-12TPE-PA, and Z-12TPE-PA) derived from different TPE derivatives and isomers. The three branches of polymers all exhibited AIE-active and “colorless-to-black” electrochromic (EC) properties. In addition to the ultrahigh fluorescence contrast, Z-12TPE-PA also integrated high electrochromic contrast (Δ% T = 92%), short response time (0.6 s/0.3 s), and excellent switching stability (300 cycles), paving the way for the applications in various electronic applications. The study will provide novel insights into the future design and development of high-performance EC/EFC materials.
    Publicationtype: Journal Article
      16
  • Some of the metrics are blocked by your 
    Item type:Publication,
    Synergistic effect between electroactive tetraphenyl-: P -phenylenediamine and AIE-active tetraphenylethylene for highly integrated electrochromic/electrofluorochromic performances
    (Royal Society of Chemistry (RSC), 2019-07-08) ; ; ; ;
    Switchable fluorescent materials have gained great attention due to their promising applications in sensors, memory devices and displays. However, further progress is hindered by the low fluorescence contrast, modest response speed and inferior long-term cycling stability. Based on a rational design strategy by combining a highly conjugated tetraphenyl-p-phenylenediamine (TPPA) unit and an aggregation induced emission (AIE)-active tetraphenylethylene (TPE) unit, we synthesized a novel diamine "N,N′-bis(4-aminophenyl)-N,N′-di(4-(1,2,2-triphenylethenyl)phenyl)-1,4-phenylenediamine" to construct an electro- and AIE-active polymer. In addition to the high efficiency solid-state fluorescence and the extremely stable redox properties, the resulting polymer TPE-TPPA-PA realized highly integrated emission/color dual-switchable properties, including multistage color-changing, high fluorescence on/off contrast up to 252, impressively rapid response rate (1.3/0.5 s for EC and 0.7/2.1 s for EFC processes) and excellent cycling stability over 10000 s. The demonstrated synergistic effect between stable electroactive TPPA and AIE-active TPE may provide a new pathway for further molecular design to realize high-performance emission/color dual-switchable materials.
    Publicationtype: Journal Article
      22