category » Energy

Efficient, Reliable Energy Buffer for Grid-interface Power Conversion with Switched Capacitor Architecture
  • A buffering strategy that utilizes the ability of a capacitor to efficiently operate over a wide voltage range allows increasing…


Device-level Thermal Analysis of GaN-based Electronics
  • Gallium nitride (GaN)-based electronics are one of the most exciting areas of innovation for high-frequency and high-voltage semiconductor devices. Although…


Graphene Cathode-based ZnO Nanowire Hybrid Solar Cells
  • Semiconducting nanowire-based solar cells have gained interest because of their potential to achieve one-dimensional charge transport pathways and large interfacial…


ZnO Nanowire Arrays for Enhanced Photocurrent in PbS Quantum Dot Solar Cells
  • Here we demonstrate a solution-processed ordered bulk heterojunction quantum dot (QD) solar cell with AM1.5G power conversion efficiencies of up…


Flexible High-Density MoS2 Sensor Arrays for Monitoring Action Potentials
  • Monolayer MoS2, a transition metal dichalcogenide, is a novel flexible semiconducting material with a 1.8 eV direct band gap.  Recent…


Low-power Memory Circuits
  • Transistor scaling has resulted in integration of more functionality on a single die. On-chip memories are responsible for a large…


Cell-based Sensors for Measuring Impact of Microsystems on Cell Physiology
  • The use of microsystems to manipulate and study cells in microenvironments is continually increasing.  However, along with such increase in…


Nano-patterning of J-aggregate Thin Films
  • We show patterning of thin J-aggregate[1] films using nano-imprinting. Unlike the conventional microfabrication techniques, such as direct-write or lift-off processes,…


Universal Village: Our Desired Living Conditions
  • Due to the growing populations in cities, resources for city and village residents have become scare while costs for public…


Recombination Dynamics of Charge Carriers in Nanostructured Solar Cells
  • Nanostructured solar cells attract increasing attention as a promising photovoltaic (PV) technology[1]. Generation of free charge carriers in nanostructured PV…


Electronic Transport Studies of Thin Film Bi and Bi1-xSbx
  • Currently bulk Bi and BixSb1-x­ have the best known thermoelectric (TE) properties at cryogenic temperatures. These properties can be further…


Micron- and Submicron-thick Parylene Substrates for Transfer Printing and Solar Applications
  • Transfer printing of thin metal films enables the fabrication of both planar and suspended membrane electrodes for microelectromechanical (MEMS) sensors…


Effect of Morphology in Quantum Dot Electronics
  • Quantum dots (QDs) are exciting materials because their bandgap is dependent on the dot size. The use of QDs allows…


Applications of Nanoimprinted Structures In Organic Photovoltaics
  • Small-molecule organic photovoltaic cells (OPVs) have the potential to be a low-cost, flexible power conversion solution to many energy problems[1]….


Self-aligned Gated Tip Arrays for Low-voltage, High-pressure Field Ionization of Gases
  • Field ion sources operate based on field ionization (FI) phenomena in which an electron tunnels out of a molecule under…


Methodology for the Optimal Design of PEV Charging Systems with Multiple Chargers and Distributed Resources
  • Increased penetration of plug-in electric vehicles (PEVs) will necessitate deployment of a large number of PEV chargers[1],[2], but chargers can…


Heat Transport in Nanostructured Materials
  • Thermal management in nanoscale materials dramatically affects the efficiency of novel energy generation technologies, and engineering devices with appropriate heat…


Self-similarity of Contact Line Depinning from Textured Superhydrophobic Surfaces
  • We report a technique for observing the dynamic behavior of a liquid contact line on superhydrophobic surfaces at high magnification…


Improved Carbon Nanotube Ultracapacitor Electrodes for Storage
  • Due to their mechanical, thermal, and electrical properties and their natural ability to grow on a variety of metallic and…


Figure 1
Materials and Structures for Li-air Batteries
  • Lithium-air batteries hold promise for the next generation of electric vehicles and other applications. By reacting oxygen directly with lithium…


Condensation on Micro/Nanostructured Superhydrophobic Surfaces
  • Water condensation on surfaces is a ubiquitous phase-change process that plays a crucial role in nature and across a range…


Design and Fabrication of a Si Sub-cell for Multi-junction GaAsP/Si Solar Cells
  • This work is part of a collaborative program aimed at ultimately achieving photovoltaic conversion with more than 40% efficiency at…


Spatially Resolved Exciton Dynamics in Quantum Dot Thin Films
  • The diffusion of excitonic energy from within the photosensitive layer of a photovoltaic cell towards the charge separation interface is…


Wide-bandwidth, Low-frequency, Low-g Piezoelectric MEMS Energy Harvesters
  • Our group proposes the piezoelectric energy harvester based on a nonlinear resonator to address the narrow bandwidth issue of conventional…


Lubricant-Impregnated Nanotextured Surfaces for Efficient Heat Transfer during Condensation
  • Despite years of advancement in making energy systems more efficient, the predominant mode of condensation seen in large-scale industrial processes…


Hydrophobic Rare-earth Oxide Ceramics with Applications to Sustained Dropwise Condensation
  • Hydrophobic materials that are robust to harsh environments are needed in a broad range of applications[1][2][3]. Although durable materials such…


Sheared Electroconvective Vortices in Electrodialysis
  • We consider electroconvective fluid flows initiated by ion concentration polarization (ICP) under pressure-driven shear flow, a scenario found in many…


Optimizing Emitter-to-Absorber Area Ratio for Improved Efficiency in Planar Solar Thermophotovoltaics
  • Solar thermophotovoltaic (STPV) devices have the potential to overcome the Shockley-Queisser limit by converting solar radiation to a narrow-band thermal…


Nano-thin Encapsulation of Photovoltaics via Atomic Layer Deposition
  • Device lifetime is a key figure of merit for solar cells and impacts the levelized energy cost ( $/(kW*hr) )…


Scalable Superhydrophobic Copper Oxide Surfaces for Enhanced Heat Transfer
  • Vapor condensation is observed in everyday life and routinely utilized in industry as an effective means of transferring heat. In…


Properties of Polymorphs of Belite
  • Portland cement clinker contains four major phases; alite (C3S) is the most dominant (50-70% by mass) and highly reactive with…


Understanding the Light Emission Mechanisms in InGaN by Correlating its Structural and Optical Properties
  • Solid state light-emitting diodes (LEDs) containing InxGa1-xN (0 ≤ x ≤ 1)/GaN hetrostructures as active components are of particular importance…


Engineering Energy Level Alignment in Lead Sulfide Quantum- Dot Photovoltaics through Ligand Exchange
  • Solar cells based on lead sulfide colloidal quantum dots (PbS QDs) have made dramatic improvements in efficiency in recent years,…


Utilization of Doped-ZnO and Related Materials Systems for Transparent Conducting Electrodes
  • Efficient transparent electrode materials are vital for applications in smart window, LED display, and solar cell technologies.  These materials must…


Direct Solar to Hydrogen Conversion: Low Cost Photoelectrodes
  • With continuously growing energy demands, alternative emission-free solar-energy solutions become ever more attractive. However, to achieve sustainability, efficient conversion and…


Self-assisted GaAs Nanowire Growth by MOCVD
  • Nanowires combine the intrinsic properties of semiconductors with low dimensionality, which makes them potential building blocks for optoelectronic applications. GaAs…


Chemomechanics of Fuel-cell-related Materials
  • Solid oxide fuel cells (SOFCs) convert chemical energy directly into electrical energy with higher efficiency and lower emission than conventional…


Investigation of Fuel Cell Cathode Performance in Solid Oxide Fuel Cells – Application of Model Thin Film Structures
  • Understanding the oxygen reduction reaction (ORR) kinetics at solid oxide fuel cell (SOFC) cathodes is considered critical for enhanced performance,…


Structured Silicon for Energy Storage in Microsystems
  • Micro-batteries provide a critical component for self-powered autonomous microsystems. Lithium-ion batteries provide relatively high energy storage capacities.  Improvement in energy…