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We observed highly efficient generation of electron-hole pairs due to impact excitation in single-walled carbon nanotube p-n junction photodiodes. Optical excitation into the second electronic subband E22 leads to striking photocurrent steps in the device I-V(SD) characteristics that occur at voltage intervals of the band-gap energy E(GAP)/e. Spatially and spectrally resolved photocurrent combined with temperature-dependent studies suggest that these steps result from efficient generation of multiple electron-hole pairs from a single hot E22 carrier. This process is both of fundamental interest and relevant for applications in future ultra-efficient photovoltaic devices.
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http://dx.doi.org/10.1126/science.1176112 | DOI Listing |
Langmuir
September 2025
Department of Materials Science and Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi 110016, India.
This study presents a novel photovoltaic triboelectric nanogenerator (PTENG) that operates on sliding contacts between n-type (gallium arsenide) GaAs and metal electrodes in the presence of periodic light illumination, which offers harvesting energy synergistically by integrating both photovoltaic and triboelectric effects to enhance the energy output. Using an in-house built test setup with provision of laser illumination, the open-circuit voltage () and short-circuit current () were measured for the n-GaAs semiconductors with different metal contacts (Al and Cu). Under both laser light (630 nm) and without laser light conditions, n-GaAs with aluminum contacts exhibited the highest and values, reaching up to 11.
View Article and Find Full Text PDFNanomaterials (Basel)
August 2025
College of Integrated Circuit Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Perovskite solar cells (PSCs) have emerged as a promising contender in photovoltaics, owing to their rapidly advancing power conversion efficiencies (PCEs) and compatibility with low-temperature solution processing techniques. Single-junction architectures reveal inherent limitations imposed by the Shockley-Queisser (SQ) limit, motivating adoption of a dual-absorber structure comprising CsCuSbCl (CCSC) and CsTiI (CTI)-lead-free perovskite derivatives valued for environmental benignity and intrinsic stability. Comprehensive theoretical screening of 26 electron/hole transport layer (ETL/HTL) candidates identified SrTiO (STO) and CuSCN as optimal charge transport materials, producing an initial simulated PCE of 16.
View Article and Find Full Text PDFNat Mater
August 2025
Department of Physics, University of California, Berkeley, CA, USA.
Excitonic insulators represent a unique quantum phase of matter that enables the study of exotic quantum bosonic states. Strongly coupled electron-hole bilayers, which host stable dipolar exciton fluids with an exciton density that can be adjusted electrostatically, offer an ideal platform to investigate correlated excitonic insulators. On the basis of electron-hole bilayers made of MoSe/hexagonal boron nitride/WSe heterostructures, here we study the behaviour of excitonic insulators in a perpendicular magnetic field.
View Article and Find Full Text PDFBeilstein J Org Chem
July 2025
Department of Chemistry, Indian Institute of Technology Kanpur, Kanpur 208016, UP, India.
Manipulating the energy barrier and extending the half-life of nonequilibrium states in photochromic switches presents viable solutions for applying them in molecular electronics. Typically, the half-life of the isomer of azobenzene (AB) is a few days. Arylazopyrazole-based molecular switches are one of the profoundly explored systems in recent times due to their superior bidirectional photoswitching and long half-life (over a thousand days at room temperature) of isomers.
View Article and Find Full Text PDFACS Nano
August 2025
CAS Key Laboratory of Nano-Bio Interface, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China.
Sonodynamic therapy (SDT) has demonstrated promising potential in the treatment of tumors and has attracted widespread attention. The majority of sound-sensitive materials developed to date have been categorized as oxygen-dependent type II sonosensitizers (SSs), which are susceptible to tumor hypoxia and significantly limit their efficacy. In this study, highly active porphyrin-based metal-organic frameworks (Yb-TCPP PMOF) with type I/II SDT dual actions were constructed by regulating the electron transfer process between metal nodes and ligands, which can produce multiple reactive oxygen species (ROS) such as O, O, and •OH.
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