The yaq project: Standardized software enabling flexible instrumentation.

Modern instrumentation development often involves the incorporation of many dissimilar hardware peripherals into a single unified instrument. The increasing availability of modular hardware has brought greater instrument complexity to small research groups. This complexity stretches the capability of traditional, monolithic orchestration software.

The Wisconsin Oscillator: A Low-Cost Circuit for Powering Ion Guides, Funnels, and Traps.

In this work, we present the Wisconsin Oscillator, a small, inexpensive, low-power circuit for powering ion-guiding devices such as multipole ion guides, ion funnels, active ion-mobility devices, and non-mass-selective ion traps. The circuit can be constructed for under $30 and produces two antiphase RF waveforms of up to 250 V in the high kilohertz to low megahertz range while drawing less than 1 W of power. The output amplitude is determined by a 0-6.

Multichannel gas-uptake/evolution reactor for monitoring liquid-phase chemical reactions.

The design of a headspace pressure-monitoring reactor for measuring the uptake/evolution of gas in gas-liquid chemical transformations is described. The reactor features a parallel setup with ten-reactor cells, each featuring a low working volume of 0.2-2 ml, a pressure capacity from 0 to 150 PSIa, and a high sensitivity pressure transducer.

Versatile Open-Source Photoreactor Architecture for Photocatalysis Across the Visible Spectrum.

Adoption of commercial photoreactors as standards for photocatalysis research could be limited by high cost. We report the development of the Wisconsin Photoreactor Platform (WPP), an open-source photoreactor architecture potentially suitable for general adoption. The WPP integrates inexpensive commercial components and common high-intensity LEDs in a 3D-printed enclosure.

The XyloTron: Flexible, Open-Source, Image-Based Macroscopic Field Identification of Wood Products.

Forests, estimated to contain two thirds of the world's biodiversity, face existential threats due to illegal logging and land conversion. Efforts to combat illegal logging and to support sustainable value chains are hampered by a critical lack of affordable and scalable technologies for field-level inspection of wood and wood products. To meet this need we present the XyloTron, a complete, self-contained, multi-illumination, field-deployable, open-source platform for field imaging and identification of forest products at the macroscopic scale.

Three Dimensional Triply Resonant Sum Frequency Spectroscopy Revealing Vibronic Coupling in Cobalamins: Toward a Probe of Reaction Coordinates.

Triply resonant sum frequency (TRSF) spectroscopy is a fully coherent mixed vibrational-electronic spectroscopic technique that is ideally suited for probing the vibrational-electronic couplings that become important in driving reactions. We have used cyanocobalamin (CNCbl) and deuterated aquacobalamin (DOCbl) as model systems for demonstrating the feasibility of using the selectivity of coherent multidimensional spectroscopy to resolve electronic states within the broad absorption spectra of transition metal complexes and identify the nature of the vibrational and electronic state couplings. We resolve three short and long axis vibrational modes in the vibrationally congested 1400-1750 cm region that are individually coupled to different electronic states in the 18 000-21 000 cm region but have minimal coupling to each other.

Exploring Electronic Structure and Order in Polymers via Single-Particle Microresonator Spectroscopy.

PSS, a transparent electrically conductive polymer, finds widespread use in electronic devices. While empirical efforts have increased conductivity, a detailed understanding of the coupled electronic and morphological landscapes in PEDOT:PSS has lagged due to substantial structural heterogeneity on multiple length-scales. We use an optical microresonator-based absorption spectrometer to perform single-particle measurements, providing a bottom-up examination of electronic structure and morphology ranging from single PEDOT:PSS polymers to nascent films.

Frequency-domain coherent multidimensional spectroscopy when dephasing rivals pulsewidth: Disentangling material and instrument response.

Ultrafast spectroscopy is often collected in the mixed frequency/time domain, where pulse durations are similar to system dephasing times. In these experiments, expectations derived from the familiar driven and impulsive limits are not valid. This work simulates the mixed-domain four-wave mixing response of a model system to develop expectations for this more complex field-matter interaction.

Measurement of Ultrafast Excitonic Dynamics of Few-Layer MoS2 Using State-Selective Coherent Multidimensional Spectroscopy.

We report the first coherent multidimensional spectroscopy study of a MoS2 film. A four-layer sample of MoS2 was synthesized on a silica substrate by a simplified sulfidation reaction and characterized by absorption and Raman spectroscopy, atomic force microscopy, and transmission electron microscopy. State-selective coherent multidimensional spectroscopy (CMDS) on the as-prepared MoS2 film resolved the dynamics of a series of diagonal and cross-peak features involving the spin-orbit split A and B excitonic states and continuum states.

Solution growth of single crystal methylammonium lead halide perovskite nanostructures for optoelectronic and photovoltaic applications.

Understanding crystal growth and improving material quality is important for improving semiconductors for electronic, optoelectronic, and photovoltaic applications. Amidst the surging interest in solar cells based on hybrid organic-inorganic lead halide perovskites and the exciting progress in device performance, improved understanding and better control of the crystal growth of these perovskites could further boost their optoelectronic and photovoltaic performance. Here, we report new insights on the crystal growth of the perovskite materials, especially crystalline nanostructures.

Ionization of high-density deep donor defect states explains the low photovoltage of iron pyrite single crystals.

Iron pyrite (FeS2) is considered a promising earth-abundant semiconductor for solar energy conversion with the potential to achieve terawatt-scale deployment. However, despite extensive efforts and progress, the solar conversion efficiency of iron pyrite remains below 3%, primarily due to a low open circuit voltage (VOC). Here we report a comprehensive investigation on {100}-faceted n-type iron pyrite single crystals to understand its puzzling low VOC.