Developing high‐efficiency and affordable electrocatalysts for the sluggish oxygen evolution reaction (OER) remains a crucial bottleneck on the way to the practical applications of rechargeable ...energy storage technologies and water splitting for producing clean fuel (H2). In recent years, NiFe‐based materials have proven to be excellent electrocatalysts for OER. Understanding the characteristics that affect OER activity and determining the OER mechanism are of vital importance for the development of OER electrocatalysts. Therefore, in situ characterization techniques performed under OER conditions are urgently needed to monitor the key intermediates together with identifying the OER active centers and phases. In this Minireview, recent advances regarding in situ techniques for the characterization of NiFe‐based electrocatalysts are thoroughly summarized, including Raman spectroscopy, X‐ray absorption spectroscopy, ambient pressure X‐ray photoelectron spectroscopy, Mössbauer spectroscopy, Ultraviolet–visible spectroscopy, differential electrochemical mass spectrometry, and surface interrogation scanning electrochemical microscopy. The results from these in situ measurements not only reveal the structural transformation and the progressive oxidation of the catalytic species under OER conditions, but also disclose the crucial role of Ni and Fe during the OER. Finally, the need for developing new in situ techniques and theoretical investigations is discussed to better understand the OER mechanism and design promising OER electrocatalysts.
What happens to the catalyst? NiFe‐based electrocatalysts undergo a structural transformation and progressive oxidation during the oxygen evolution reaction (OER). Recent advances regarding in situ techniques for the characterization of NiFe‐based electrocatalysts are summarized in this Minireview.
Prostate apoptosis response‐4 (Par‐4) tumor suppressor protein has gained attention as a potential therapeutic target owing to its unique ability to selectively induce apoptosis in cancer cells, ...sensitize them to chemotherapy and radiotherapy, and mitigate drug resistance. It has recently been reported that Par‐4 interacts synergistically with cisplatin, a widely used anticancer drug. However, the mechanistic details underlying this relationship remain elusive. In this investigation, we employed an array of biophysical techniques, including circular dichroism spectroscopy, dynamic light scattering, and UV–vis absorption spectroscopy, to characterize the interaction between the active caspase‐cleaved Par‐4 (cl‐Par‐4) fragment and cisplatin. Additionally, elemental analysis was conducted to quantitatively assess the binding of cisplatin to the protein, utilizing inductively coupled plasma‐optical emission spectroscopy and atomic absorption spectroscopy. Our findings provide evidence of direct interaction between cl‐Par‐4 and cisplatin, and reveal a binding stoichiometry of 1:1. This result provides insights that could be useful in enhancing the efficacy of cisplatin‐based and tumor suppressor‐based cancer therapies.
Microorganism contamination and foodborne disease outbreaks are of public concern worldwide. As such, the food industry requires rapid and nondestructive methods to detect microorganisms and to ...control food quality. However, conventional methods such as culture and colony counting, polymerase chain reaction, and immunoassay approaches are laborious, time‐consuming and require trained personnel. Therefore, the emergence of rapid analytical methods is essential. This review introduces 6 spectroscopic and spectral imaging techniques that apply infrared spectroscopy, surface‐enhanced Raman spectroscopy, terahertz time‐domain spectroscopy, laser‐induced breakdown spectroscopy, hyperspectral imaging, and multispectral imaging for microorganism detection. Recent advances of these technologies from 2011 to 2017 are outlined. Challenges in the application of these technologies for microorganism detection in food matrices are addressed. These emerging spectroscopic and spectral imaging techniques have the potential to provide rapid and nondestructive detection of microorganisms. They should also provide complementary information to enhance the performance of conventional methods to prevent disease outbreaks and food safety problems.
Soft X‐ray spectroscopy (SXS) techniques such as photoelectron spectroscopy, soft X‐ray absorption spectroscopy and X‐ray emission spectroscopy are efficient and direct tools to probe electronic ...structures of materials. Traditionally, these surface sensitive soft X‐ray techniques that detect electrons or photons require high vacuum to operate. Many recent in situ instrument developments of these techniques have overcome this vacuum barrier. One can now study many materials and model devices under near ambient, semi‐realistic, and operando conditions. Further developments of integrating the realistic sample environments with efficient and high resolution detection methods, particularly at the high brightness synchrotron light sources, are making SXS an important tool for the energy research community. In this progress report, we briefly describe the basic concept of several SXS techniques and discuss recent development of SXS instruments. We then present several recent studies, mostly in situ SXS experiments, on energy materials and devices. Using these studies, we would like to highlight that the integration of SXS and in situ environments can provide in‐depth insight of material's functionality and help researchers in new energy material developments. The remaining challenges and critical research directions are discussed at the end.
Recent instrumentation developments have advanced soft X‐ray spectroscopic tools for studying real‐world samples. Both photon‐in‐electron‐out and photon‐in‐photon‐out spectroscopy can be performed under semi‐realistic, and operando conditions through high‐efficiency and high‐resolution detection systems at high‐brightness synchrotron light sources. This Progress Report focuses on many recent advancements on in situ soft X‐ray spectroscopic tools and their applications in developing energy materials.
Vibrational spectroscopy techniques, such as Fourier-transform infrared (FTIR) and Raman spectroscopy, have been successful methods for studying the interaction of light with biological materials and ...facilitating novel cell biology analysis. Spectrochemical analysis is very attractive in disease screening and diagnosis, microbiological studies and forensic and environmental investigations because of its low cost, minimal sample preparation, non-destructive nature and substantially accurate results. However, there is now an urgent need for multivariate classification protocols allowing one to analyze biologically derived spectrochemical data to obtain accurate and reliable results. Multivariate classification comprises discriminant analysis and class-modeling techniques where multiple spectral variables are analyzed in conjunction to distinguish and assign unknown samples to pre-defined groups. The requirement for such protocols is demonstrated by the fact that applications of deep-learning algorithms of complex datasets are being increasingly recognized as critical for extracting important information and visualizing it in a readily interpretable form. Hereby, we have provided a tutorial for multivariate classification analysis of vibrational spectroscopy data (FTIR, Raman and near-IR) highlighting a series of critical steps, such as preprocessing, data selection, feature extraction, classification and model validation. This is an essential aspect toward the construction of a practical spectrochemical analysis model for biological analysis in real-world applications, where fast, accurate and reliable classification models are fundamental.
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