Out-of-plane polarization induces a picosecond photoresponse in rhombohedral stacked bilayer WSe₂

• Guixian Liu,
• Yufan Wang,
• Zhoujuan Xu,
• Zhouxiaosong Zeng,
• Lanyu Huang,
• Cuihuan Ge and
• Xiao Wang

Beilstein J. Nanotechnol. 2024, 15, 1362–1368, doi:10.3762/bjnano.15.109

• spontaneous polarization on ultrafast carrier dynamics in rhombohedral stacked bilayer WSe2. Using precise stacking techniques, a 3R WSe2-based vertical heterojunction was successfully constructed and confirmed by polarization-resolved second harmonic generation measurements. Through output characteristics

• importantly, spontaneous polarization can further modulate the photogenerated carriers, which provides the potential for self-powered switchable and ultrafast photodetectors [35][36][37]. However, the impact of polarization effects on photogenerated carrier dynamics in these artificially stacked materials

• remains unexplored. In this work, we confirmed the spontaneous OOP polarization in artificially stacked 3R WSe2 and investigated the ultrafast carrier dynamics through time-resolved photocurrent (TRPC) measurements. We fabricated 3R WSe2 through artificial stacking in parallel and validated the broken

Interface properties of nanostructured carbon-coated biological implants: an overview

• Mattia Bartoli,
• Francesca Cardano,
• Erik Piatti,
• Stefania Lettieri,
• Andrea Fin and
• Alberto Tagliaferro

Beilstein J. Nanotechnol. 2024, 15, 1041–1053, doi:10.3762/bjnano.15.85

• rings, which prevents planar deformations [33]. The same phenomenon explains the high thermal conductivity of up to 3000 W·m−1·K−1 [34][35] and the outstanding electrical properties [36][37][38]. Compared to conventional 3D materials, the understanding of electronic transport and carrier dynamics in

Bismuth-based nanostructured photocatalysts for the remediation of antibiotics and organic dyes

• Akeem Adeyemi Oladipo and
• Faisal Suleiman Mustafa

Beilstein J. Nanotechnol. 2023, 14, 291–321, doi:10.3762/bjnano.14.26

• of the host material, enhancing charge carrier dynamics [20][146]. In contrast to undoped Bi2WO6, visible light-driven 3-D hierarchical Ag-doped Bi2WO6 nanoparticles showed improved photocatalytic performance by destroying 95% of tetracycline in only 70 min, according to Shen and co-workers [147

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• and AzoOC12), which can be seen in Figure 6B. As many other charge-carrier dynamics beside the radiative recombination, such as photorecycling and surface defects, affect the PL no (bi)exponential fit could be found [53][54]. Thus, the recorded measurements are discussed qualitatively. A small spacing

Numerical analysis of single-point spectroscopy curves used in photo-carrier dynamics measurements by Kelvin probe force microscopy under frequency-modulated excitation

• Pablo A. Fernández Garrillo,
• Benjamin Grévin and
• Łukasz Borowik

Beilstein J. Nanotechnol. 2018, 9, 1834–1843, doi:10.3762/bjnano.9.175

• nanostructure and photo-transport mechanisms has become of crucial importance for the development of many emerging photovoltaic technologies. In this context, Kelvin probe force microscopy under frequency-modulated excitation has emerged as a useful technique for probing photo-carrier dynamics and gaining

• experimental results as additional information about the photo-carrier dynamics of the sample can be gained via the numerical analysis. Keywords: carrier dynamics; carrier lifetime; carrier recombination; Kelvin probe force microscopy; nanostructured photovoltaics; numerical simulations; photo-carrier

• dynamics; Introduction In the past decade, the nanoscale investigation of materials properties has captured the attention of the scientific community, partially due to its crucial importance in the improvement of photovoltaic devices [1][2]. Carrier lifetime, or more broadly speaking, photo-carrier

Artifacts in time-resolved Kelvin probe force microscopy

• Sascha Sadewasser,
• Nicoleta Nicoara and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2018, 9, 1272–1281, doi:10.3762/bjnano.9.119

• potential, which contains information about the involved charge carrier dynamics. Here, we show that such measurements are prone to artifacts due to frequency mixing, by performing numerical dynamics simulations of the cantilever oscillation in KPFM subjected to a bias-modulated signal. For square bias

• characterization, and knowledge of the nanoscale charge-carrier dynamics can provide valuable insight into device functionality and limitations in device performance. As a consequence, recently, several techniques for time-resolved measurements with time resolution down to picoseconds have been developed. In the

• time of the KPFM controller, only an averaged CPD will be measured, for which the value will depend on how fast the changes in charge carrier separation follow the light modulation. Thus, the average CPD carries information about the charge carrier dynamics. This technique was subsequently used by

Surface-plasmon-enhanced ultraviolet emission of Au-decorated ZnO structures for gas sensing and photocatalytic devices

• T. Anh Thu Do,
• Truong Giang Ho,
• Thu Hoai Bui,
• Quang Ngan Pham,
• Hong Thai Giang,
• Thi Thu Do,
• Duc Van Nguyen and
• Dai Lam Tran

Beilstein J. Nanotechnol. 2018, 9, 771–779, doi:10.3762/bjnano.9.70

• . Keywords: Au-decorated ZnO; carrier dynamics; gas sensors; photocatalyst; SPR effect; Introduction Inorganic transition metal oxide sensor devices have attracted attention in particular for improving gas sensing, energy conversion, electronics, photocatalysis and optoelectronic devices [1][2][3][4]. Among

CVD transfer-free graphene for sensing applications

• Chiara Schiattarella,
• Sten Vollebregt,
• Tiziana Polichetti,
• Brigida Alfano,
• Ettore Massera,
• Maria Lucia Miglietta,
• Girolamo Di Francia and
• Pasqualina Maria Sarro

Beilstein J. Nanotechnol. 2017, 8, 1015–1022, doi:10.3762/bjnano.8.102

• configuration of the system, is not fully representative of the complex charge carrier dynamics due to the adsorption of gas molecules on the graphene surface. Herein, additional mechanisms that affect the conductance behaviour, such as induced charge propagation within the layers of a single graphene grain, as

Carrier multiplication in silicon nanocrystals: ab initio results

• Ivan Marri,
• Marco Govoni and
• Stefano Ossicini

Beilstein J. Nanotechnol. 2015, 6, 343–352, doi:10.3762/bjnano.6.33

• cell efficiency. Effects induced by CM on the excited carrier dynamics have been observed in a wide range of systems, for instance PbSe and PbS [12][13][14][15][16], CdSe and CdTe [17][18][19], PbTe [20], InAs [21], InP [22] and Si [23]. These effects have been studied using different theoretical

• and Ei > 3.8 eV, CM is faster in Si-NC systems than in Si-bulk and is observed to be independent of the NC size. In this range of energies, CM is sufficiently fast to compete with concurrent non-CM processes and, playing a fundamental role in the determination of the excited carrier dynamics, can be

• a realistic determination of high energy, excited carrier dynamics. It is thus evident that a detailed estimation of (Ei) requires an accurate description of the atomistic properties of the systems that, especially for nanostructures, can be obtained only through a parameter-free, ab initio

Effects of palladium on the optical and hydrogen sensing characteristics of Pd-doped ZnO nanoparticles

• Anh-Thu Thi Do,
• Hong Thai Giang,
• Thu Thi Do,
• Ngan Quang Pham and
• Giang Truong Ho

Beilstein J. Nanotechnol. 2014, 5, 1261–1267, doi:10.3762/bjnano.5.140

• of zinc oxide nanoparticles on the photoluminescence (PL) properties and hydrogen sensing characteristics of gas sensors is investigated. The PL intensity shows that the carrier dynamics coincides with the buildup of the Pd-related green emission. The comparison between the deep level emission and

• : carrier dynamics; hydrogen sensing; Pd-doped ZnO; photoluminescence; sensor; Introduction Semiconductor zinc oxides (ZnO) nanocrystals are not only interesting for fundamental physics, but they are also important for both optoelectronic and emerging electronic device applications, in particular for

• nanoscale particle size of 16.2 and 16.5 nm and with a large specific surface area of 37.5 and 34.32 m2/g, respectively, were prepared by wet chemical methods for gas sensor fabrication. The PL spectra at room temperature show that the carrier dynamics coincides with the buildup of the Pd-related green

Kelvin probe force microscopy of nanocrystalline TiO₂ photoelectrodes

• Alex Henning,
• Gino Günzburger,
• Res Jöhr,
• Yossi Rosenwaks,
• Biljana Bozic-Weber,
• Catherine E. Housecroft,
• Edwin C. Constable,
• Ernst Meyer and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2013, 4, 418–428, doi:10.3762/bjnano.4.49

• ., surface topography and potential, are still unclear and have the potential to increase the efficiency and long-term stability of the devices. Investigations of nanoscaled photovoltaic devices require nanometer-scale measuring methods, including time-resolved measurements of the carrier dynamics [15][16

• ) TiO2 have been investigated with such a macroscopic Kelvin probe (KP) revealing details about the electronic structure [21][22][23], trap states [24], the surface dipole [25], charge-carrier dynamics [26], and indicating changes upon chemical treatments [24][27][28][29]. KP studies have helped to

• light, i.e., super- or sub-bandgap(TiO2) illumination. Both SPV effects are described separately in the following two sections. Time-resolved SPV measurements provide insights into charge carrier dynamics [45] and are described below. Surface photovoltage under super-bandgap illumination SPV