Abstract: The present disclosure may provide semiconductor perovskite layers and method of making thereof. In some cases, the perovskite layer may comprise a composition of MAn1FAn2Csn3PbX3. MA may be methylammonium, FA may be formamidinium, n1, n2, and n3 may independently be greater than 0 and less than 1, and n1+n2+n3 may equal 1.

Abstract: The present disclosure may provide semiconductor perovskite layers and method of making thereof. In some cases, the perovskite layer may comprise a composition of MAn1FAn2Csn3PbX3. MA may be methylammonium, FA may be formamidinium, n1, n2, and n3 may independently be greater than 0 and less than 1, and n1 + n2 + n3 may equal 1.

Abstract: The present disclosure provides a tandem, 4-terminal, silicon-perovskite solar device. The device may comprise a silicon solar cell having a first band gap; a glass sheet covering the silicon solar cell, wherein the glass sheet comprises a top surface and a bottom surface; and a perovskite solar cell having a second band gap, wherein the perovskite solar cell is deposited on the bottom surface of the glass sheet.

Abstract: A handheld XRF device having a shutter including a calibration material. An automatic calibration sequence may be performed with the shutter in the closed position.

Abstract: A handheld XRF device having a shutter including a calibration material. An automatic calibration sequence may be performed with the shutter in the closed position.

Abstract: Techniques are used to fabricate carbon nanotube devices. These techniques improve the selective removal of undesirable nanotubes such as metallic carbon nanotubes while leaving desirable nanotubes such as semiconducting carbon nanotubes. In a first technique, slot patterning is used to slice or break carbon nanotubes have a greater length than desired. By altering the width and spacing of the slotting, nanotubes have a certain length or greater can be removed. Once the lengths of nanotubes are confined to a certain or expected range, the electrical breakdown approach of removing nanotubes is more effective. In a second technique, a Schottky barrier is created at one electrode (e.g., drain or source). This Schottky barrier helps prevent the inadvertent removal the desirable nanotubes when using the electrical breakdown approach. The first and second techniques can be used individually or in combination with each other.

Abstract: A method of making a microfluidic device is provided. The method features patterning a permeable wall on a substrate, and surrounding the permeable wall with a solid, non-permeable boundary structure to establish a microfluidic channel having a cross-sectional dimension less than 5,000 microns and a cross-sectional area at least partially filled with the permeable wall so that fluid flowing through the microfluidic channel at least partially passes through the permeable wall.

Abstract: Methods and devices for spectroscopic identification of molecules using nanoscale wires are disclosed. According to one of the methods, nanoscale wires are provided, electrons are injected into the nanoscale wire; and inelastic electron scattering is measured via excitation of low-lying vibrational energy levels of molecules bound to the nanoscale wire.

Abstract: Methods and devices for spectroscopic identification of molecules using nanoscale wires are disclosed. According to one of the methods, nanoscale wires are provided, electrons are injected into the nanoscale wire; and inelastic electron scattering is measured via excitation of low-lying vibrational energy levels of molecules bound to the nanoscale wire.

Abstract: Switches having an in situ grown carbon nanotube as an element thereof, and methods of fabricating such switches. A carbon nanotube is grown in situ in mechanical connection with a conductive substrate, such as a heavily doped silicon wafer or an SOI wafer. The carbon nanotube is electrically connected at one location to a terminal. At another location of the carbon nanotube there is situated a pull electrode that can be used to elecrostatically displace the carbon nanotube so that it selectively makes contact with either the pull electrode or with a contact electrode. Connection to the pull electrode is sufficient to operate the device as a simple switch, while connection to a contact electrode is useful to operate the device in a manner analogous to a relay. In various embodiments, the devices disclosed are useful as at least switches for various signals, multi-state memory, computational devices, and multiplexers.

Abstract: Switches having an in situ grown carbon nanotube as an element thereof, and methods of fabricating such switches. A carbon nanotube is grown in situ in mechanical connection with a conductive substrate, such as a heavily doped silicon wafer or an SOI wafer. The carbon nanotube is electrically connected at one location to a terminal. At another location of the carbon nanotube there is situated a pull electrode that can be used to electrostatically displace the carbon nanotube so that it selectively makes contact with either the pull electrode or with a contact electrode. Connection to the pull electrode is sufficient to operate the device as a simple switch, while connection to a contact electrode is useful to operate the device in a manner analogous to a relay. In various embodiments, the devices disclosed are useful as at least switches for various signals, multi-state memory, computational devices, and multiplexers.