A Mixture of Negative‑, Zero‑, and Positive-Differential Transconductance Switching from Tellurium/Indium Gallium Zinc Oxide Heterostructures

Conventional transistors have long emphasized signal modulation and amplification, often sidelining polarity considerations. However, the recent emergence of negative differential transconductance, characterized by a drain current decline during gate voltage sweeping, has illuminated an unconventional path in transistor technology. This phenomenon promises to simplify the implementation of ternary logic circuits and enhance energy efficiency, especially in multivalued logic applications. Our research has culminated in the development of a sophisticated mixed transconductance transistor (M-T device) founded on a precise Te and IGZO heterojunction. The M-T device exhibits a sequence of intriguing phenomena, zero differential transconductance (ZDT), positive differential transconductance (PDT), and negative differential transconductance (NDT) contingent on applied gate voltage. We clarify its operation using a three-segment equivalent circuit model and validate its viability with IGZO TFT, Te TFT, and Te/IGZO TFT components. In a concluding demonstration, the M-T device interconnected with Te TFT achieves a ternary inverter with an intermediate logic state. Remarkably, this configuration seamlessly transitions into a binary inverter when it is exposed to light

Lithography-Free, Large-Area Spatially Segmented Disordered Structure for Light Harvesting in Photovoltaic Modules

Optical losses in photovoltaic (PV) systems cause nonradiative recombination or incomplete absorption of incident light, hindering the attainment of high energy conversion efficiency. The surface of the PV cells is encapsulated to not only protect the cell but also control the transmission properties of the incident light to promote maximum conversion. Despite many advances in elaborately designed photonic structures for light harvesting, the complicated process and sophisticated patterning highly diminish the cost-effectiveness and further limit the mass production on a large scale. Here, we propose a robust/comprehensive strategy based on the hybrid disordered photonic structure, implementing multifaceted light harvesting with an affordable/scalable fabrication method. The spatially segmented structures include (i) nanostructures in the active area for antireflection and (ii) microstructures in the inactive edge area for redirecting the incident light into the active area. A lithography-free hybrid disordered structure fabricated by the thermal dewetting method is a facile approach to create a large-area photonic structure with hyperuniformity over the entire area. Based on the experimentally realized nano-/microstructures, we designed a computational model and performed an analytical calculation to confirm the light behavior and performance enhancement. Particularly, the suggested structure is manufactured by the elastomeric stamps method, which is affordable and profitable for mass production. The produced hybrid structure integrated with the multijunction solar cell presented an improved efficiency from 28.0 to 29.6% by 1.06 times

Plasmonic Silver Nanoparticle-Impregnated Nanocomposite BiVO₄ Photoanode for Plasmon-Enhanced Photocatalytic Water Splitting

Herein, we developed a fully solution-deposited nanocomposite photoanode based on silver nanoparticle (NP)-impregnated bismuth vanadate (BiVO₄) films. The synthesized Ag NPs exhibit diameters of few nanometers and uniform matrix dispersion, which were confirmed by high-resolution transmission electron microscopy. The photoanode composed of the Ag NP-incorporated nanocomposite BiVO₄ showed a remarkable enhancement in both low potential and the saturated photocatalytic current densities in comparison with the pristine BiVO₄ film. The observed experimental results are attributed to the improved carrier generation and enhanced charge separation by the localized surface plasmon resonance-mediated effect as suggested by electrochemical impedance spectroscopy and a numerical simulation