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Electrospray ionization mass spectrometry (ESI‐MS) is an analytical technique that measures the mass of a sample through “soft” ionization. Recent years have witnessed a rapid growth of its application in noble‐metal nanocluster (NC) analysis. ESI‐MS is able to provide the mass of a noble‐metal NC analyte for the analysis of their composition (n, m, q values in a general formula [MnLm]q), which is crucial in understanding their properties. This review attempts to present various developed techniques for the determination of the composition of noble metal NCs by ESI‐MS. Additionally, advanced applications that use ESI‐MS to further understand the reaction mechanism, complexation behavior, and structure of noble metal NCs are introduced. From the comprehensive applications of ESI‐MS on noble‐metal NCs, more possibilities in nanochemistry can be opened up by this powerful technique.

Biomass fractionation is a prerequisite for almost any biorefinery process. Yet, a cost-effective and environmentally benign approach to separate biomass feedstock into valuable fractions remain a challenge. Herein we introduce a new fractionation method to extract high value chitin from crustacean shell (e.g., shrimp shell) using hot water for deproteinization and carbonic acid for demineralization (termed as the HOW-CA process). This method features high deproteinization and demineralization efficiencies (>90%), and the whole process is accomplished within hours. The desired final product chitin exhibits a high purity. This work addresses the major problems associated with the current industrial practice including the employment of corrosive reagents, the destructive removal of a useful component, and the generation of a large amount of waste. Economic and life-cycle analyses imply that the HOW-CA process is superior to the conventional method, offering both economic and environmental benefits.

In this work, the effects of thiolate ligands (-SR, e.g., chain length and functional moiety) on the accessibility and catalytic activity of thiolate-protected gold nanoclusters (e.g., Au (SR) ) for 4-nitrophenol hydrogenation is reported. The data suggest that Au (SR) bearing a shorter alkyl chain shows a better accessibility to the substrates (shown by shorter induction time, t ) and a higher catalytic activity (shown by higher apparent reaction rate constant, k ). The functional moiety of the ligands is another determinant factor, which clearly suggests that ligand engineering of Au (SR) would be an efficient platform for fine-tuning its catalytic properties.