A visible-light photodetector based on heterojunctions between CuO nanoparticles and ZnO nanorods

• Doan Nhat Giang,
• Nhat Minh Nguyen,
• Duc Anh Ngo,
• Thanh Trang Tran,
• Le Thai Duy,
• Cong Khanh Tran,
• Thi Thanh Van Tran,
• Phan Phuong Ha La and
• Vinh Quang Dang

Beilstein J. Nanotechnol. 2023, 14, 1018–1027, doi:10.3762/bjnano.14.84

• 84.64 s, respectively. The fall time is relatively long because the photodetector is influenced by the persistent photoconductivity (PCC) effect [42]. The origin of PCC are adsorption and desorption processes of oxygen molecules. The re-adsorption rate of oxygen molecules is slow and a stable state is

Absorption and photoconductivity spectra of amorphous multilayer structures

• Oxana Iaseniuc and
• Mihail Iovu

Beilstein J. Nanotechnol. 2020, 11, 1757–1763, doi:10.3762/bjnano.11.158

• Oxana Iaseniuc Mihail Iovu Institute of Applied Physics, No. 5 Academiei Str., Chisinau, MD-2028, R. Moldova 10.3762/bjnano.11.158 Abstract The experimental results regarding optical absorption and steady-state photoconductivity of amorphous single-layer structures (Al–As0.40S0.30Se0.30–Al, Al

• spectra and the kinetics of the photocurrent can provide information regarding the mechanisms of generation, recombination, and drift processes of non-equilibrium carriers in amorphous materials. Thus, investigations of stationary and transient characteristics of the photoconductivity of ternary amorphous

• Sn impurities on stationary and transient photoconductivity was demonstrated for amorphous As2Se3Snx thin films [5]. The introduction of Sn in the host material increases the drift mobility and the photosensitivity of the amorphous material. According to 119Sn Mössbauer spectroscopy studies of the

Excitonic and electronic transitions in Me–Sb₂Se₃ structures

• Nicolae N. Syrbu,
• Victor V. Zalamai,
• Ivan G. Stamov and
• Stepan I. Beril

Beilstein J. Nanotechnol. 2020, 11, 1045–1053, doi:10.3762/bjnano.11.89

• the Brillouin zone space are also ambiguous [6][8][10][19][20]. The crystalline properties of Sb2Sе3, such as optical absorption, reflection, and photoconductivity, were studied in this work. In order to determine the bandgap, the nature of electronic transitions, among other properties, the

• Brillouin zone center. The effective mass of the electrons and holes was calculated as well as the anisotropy of the latter. The photoconductivity measurements were performed in the excitonic region at positive and negative voltages applied to the Me–Sb2Se3 contacts. A similar investigation using the Sb2S3

• crystal layers were characterized by a high reflectance, which is characteristic of metallic aluminum mirrors. Some measurements were also carried out on the spectrometer DFS-32 coupled with a Specord M-40 and a Jasco V-670. The photoconductivity spectra were obtained on a single spectrometer (MDR-2) with

Electrochemical nanostructuring of (111) oriented GaAs crystals: from porous structures to nanowires

• Elena I. Monaico,
• Eduard V. Monaico,
• Veaceslav V. Ursaki,
• Shashank Honnali,
• Vitalie Postolache,
• Karin Leistner,
• Kornelius Nielsch and
• Ion M. Tiginyanu

Beilstein J. Nanotechnol. 2020, 11, 966–975, doi:10.3762/bjnano.11.81

• followed by 250 nm Au layer was sputtered using a magnetron from Torr International Inc model No: CRC622-2G2-RF-DC and lift-off was performed with Microposit remover 1165 at 50 °C. Photoelectrical characterization. To excite photoconductivity in the GaAs nanowires, the radiation from a Xenon lamp DKSS-150

• was used. An optical filter was used to select radiation from the near-IR spectral range (700–2500 nm, optical power 130 mW). The current through the samples was measured by means of a Keithley’s Series 2400 source measure unit. Since the photoconductivity decay time is long enough, a mechanical

Band tail state related photoluminescence and photoresponse of ZnMgO solid solution nanostructured films

• Vadim Morari,
• Aida Pantazi,
• Nicolai Curmei,
• Vitalie Postolache,
• Emil V. Rusu,
• Marius Enachescu,
• Ion M. Tiginyanu and
• Veaceslav V. Ursaki

Beilstein J. Nanotechnol. 2020, 11, 899–910, doi:10.3762/bjnano.11.75

• long duration relaxation of photoconductivity was shown to be characteristic for films prepared by spin coating, while a fast response to irradiation was observed in samples prepared by aerosol spray pyrolysis. Similar to the issues about the influence of the technology on the morphology of films

• to the higher concentration of acceptor levels introduced during spin coating. Long duration relaxation of photoconductivity and persistent photoconductivity was previously observed in highly doped and compensated semiconductors [39], porous semiconductors [48] and solid solutions [40]. The origin of

• long duration component in the relaxation of photoconductivity in ZnMgO films deposited by spin-coating corroborates the data deduced from the analysis of photoluminescence spectra. At the same time, the lack of such a component in films prepared by aerosol deposition may be interpreted as reduced

Non-equilibrium electron transport induced by terahertz radiation in the topological and trivial phases of Hg_1−xCd_xTe

• Alexandra V. Galeeva,
• Alexey I. Artamkin,
• Alexey S. Kazakov,
• Sergey N. Danilov,
• Sergey A. Dvoretskiy,
• Nikolay N. Mikhailov,
• Ludmila I. Ryabova and
• Dmitry R. Khokhlov

Beilstein J. Nanotechnol. 2018, 9, 1035–1039, doi:10.3762/bjnano.9.96

• . 53, 119991 Moscow, Russia 10.3762/bjnano.9.96 Abstract Terahertz photoconductivity in heterostructures based on n-type Hg1−xCdxTe epitaxial films both in the topological phase (x < 0.16, inverted band structure, zero band gap) and the trivial state (x > 0.16, normal band structure) has been studied

• . We show that both the positive photoresponse in films with x < 0.16 and the negative photoconductivity in samples with x > 0.16 have no low-energy threshold. The observed non-threshold positive photoconductivity is discussed in terms of a qualitative model that takes into account a 3D potential well

• and 2D topological Dirac states coexisting in a smooth topological heterojunction. Keywords: terahertz radiation; topological insulator; photoconductivity; Findings Discovery of theoretically predicted quantum spin Hall effect states in HgTe quantum wells [1][2] has initiated extensive studies of

Combined pulsed laser deposition and non-contact atomic force microscopy system for studies of insulator metal oxide thin films

• Daiki Katsube,
• Hayato Yamashita,
• Satoshi Abo and
• Masayuki Abe

Beilstein J. Nanotechnol. 2018, 9, 686–692, doi:10.3762/bjnano.9.63

• grown on substrate materials have been studied for correlated electron heterostructures and devices. One of the most important and common uses of epitaxial LaAlO3 is its interface with SrTiO3 for studies of electrical conductivity [4], superconductivity [59], photoconductivity [60], and

Sb₂S₃ grown by ultrasonic spray pyrolysis and its application in a hybrid solar cell

• Erki Kärber,
• Atanas Katerski,
• Ilona Oja Acik,
• Arvo Mere,
• Valdek Mikli and
• Malle Krunks

Beilstein J. Nanotechnol. 2016, 7, 1662–1673, doi:10.3762/bjnano.7.158

• to white light, as opposed to the I–V measurements performed under the A.M1.5 conditions. The photoconductivity of the hole conductor, as discussed above, might also contribute to the variance between the integrated EQE and the JSC. Table 1 also presents the JSC of 6 mA·cm−2 for a cell that had seven

Nanostructured germanium deposited on heated substrates with enhanced photoelectric properties

• Ionel Stavarache,
• Valentin Adrian Maraloiu,
• Petronela Prepelita and
• Gheorghe Iordache

Beilstein J. Nanotechnol. 2016, 7, 1492–1500, doi:10.3762/bjnano.7.142

• generated in the Ge-nps and in the Si substrate and they move by tunneling between neighboring Ge-nps. During transport, the positively charged holes are dynamically trapped within the Ge-nps incorporated into SiO2 matrix improving the electron injection, leading to an increase of negative photoconductivity

• /SiO2/ITO fabricated without Ge-nps in the oxide thin layer shows a very weak absorption, with signals obtained only in the wavelength range specific to Si. This can be considered as a contribution from the substrate and SiO2 thin film, this phenomenon been known as negative photoconductivity [41

Electronic interaction in composites of a conjugated polymer and carbon nanotubes: first-principles calculation and photophysical approaches

• Florian Massuyeau,
• Jany Wéry,
• Jean-Luc Duvail,
• Serge Lefrant,
• Abu Yaya,
• Chris Ewels and
• Eric Faulques

Beilstein J. Nanotechnol. 2015, 6, 1138–1144, doi:10.3762/bjnano.6.115

• network when nanotubes are semiconducting. Keywords: composite; conjugated polymer; DFT calculations; energy transfer; photoconductivity; single wall carbon nanotubes; time-resolved photoluminescence; Introduction Electroactive conjugated polymers (ECPs) are technologically promising for organic light

• photoconductivity measurements. These techniques are appropriate tools to understand the energy transfer mechanisms involved by the introduction of SWNTs into the PPV polymer matrix. In particular, time-resolved PL measurements give crucial information about the nature of photogenerated charges and their migration

• at 4.64 eV with a 100 fs pulsed laser at low photon density (below 1017 cm−3) and PL images were recorded with a streak camera [16][17]. Steady-state PL spectra and quantum yields Q were measured at 3.1 eV excitation energy [18]. Photoconductivity measurements were performed at 2.54 eV with a high

Observation of a photoinduced, resonant tunneling effect in a carbon nanotube–silicon heterojunction

• Carla Aramo,
• Antonio Ambrosio,
• Michelangelo Ambrosio,
• Maurizio Boscardin,
• Paola Castrucci,
• Michele Crivellari,
• Marco Cilmo,
• Maurizio De Crescenzi,
• Francesco De Nicola,
• Emanuele Fiandrini,
• Valentina Grossi,
• Pasqualino Maddalena,
• Maurizio Passacantando,
• Sandro Santucci,
• Manuela Scarselli and
• Antonio Valentini

Beilstein J. Nanotechnol. 2015, 6, 704–710, doi:10.3762/bjnano.6.71

• mechanisms behind the infrared sensitivity of CNTs have been discussed by various authors [9][10]. The photoconductivity of individual CNTs, as well as ropes and films of CNTs have been studied extensively both in the visible [11] and the infrared [12] range. The variations in the photoconductivity of CNT

Growth evolution and phase transition from chalcocite to digenite in nanocrystalline copper sulfide: Morphological, optical and electrical properties

• Priscilla Vasthi Quintana-Ramirez,
• Ma. Concepción Arenas-Arrocena,
• José Santos-Cruz,
• Marina Vega-González,
• Omar Martínez-Alvarez,
• Víctor Manuel Castaño-Meneses,
• Laura Susana Acosta-Torres and
• Javier de la Fuente-Hernández

Beilstein J. Nanotechnol. 2014, 5, 1542–1552, doi:10.3762/bjnano.5.166

• °C. Photoconductivity of copper sulfide films, synthesized in both aqueous and organic media. Only the organic samples show photoconductivity. Scheme of the phase-transition mechanism from chalcocite to digenite and the formation of the respective nanocystals of the CuxS samples as a function of the

Photoresponse from single upright-standing ZnO nanorods explored by photoconductive AFM

• Igor Beinik,
• Markus Kratzer,
• Astrid Wachauer,
• Lin Wang,
• Yuri P. Piryatinski,
• Gerhard Brauer,
• Xin Yi Chen,
• Yuk Fan Hsu,
• Aleksandra B. Djurišić and
• Christian Teichert

Beilstein J. Nanotechnol. 2013, 4, 208–217, doi:10.3762/bjnano.4.21

• properties. Here, photoconductive atomic force microscopy (PC-AFM) has been applied to investigate transient photoconductivity and photocurrent spectra of upright-standing ZnO nanorods (NRs). With a view to evaluate the electronic properties of the NRs and to get information on recombination kinetics, we

• have also performed time-resolved photoluminescence measurements macroscopically. Results: Persistent photoconductivity from single ZnO NRs was observed for about 1800 s and was studied with the help of photocurrent spectroscopy, which was recorded locally. The photocurrent spectra recorded from single

• experiments carried out at variable oxygen pressure. Keywords: AFM; nanorods; photoconductive AFM; photoconductivity; ZnO; Introduction One-dimensional ZnO nanostructures, so called ZnO nanorods (NRs), exhibit technological potential for many device applications. Having a wide band gap (3.37 eV at room

Ultraviolet photodetection of flexible ZnO nanowire sheets in polydimethylsiloxane polymer

• Jinzhang Liu,
• Nunzio Motta and
• Soonil Lee

Beilstein J. Nanotechnol. 2012, 3, 353–359, doi:10.3762/bjnano.3.41

• nanowire film can be enhanced by PDMS coating. The responsivity of the device, defined as the photocurrent per unit of incident optical power, is determined by the UV photoconductivity of the ZnO nanowires. From the I–V curves we can deduce that the PDMS coating over ZnO nanowires results in an