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Direct synthesis of hydrogen peroxide (H₂O₂) from H₂and O₂on a Pd‐based catalyst has emerged as a promising route to replace the energy‐consuming, highly inefficient anthraquinone process. However, Pd is also a good catalyst for the decomposition of H₂O₂, thereby compromising the selectivity toward the desired product. The coupling between the formation and decomposition reactions makes it difficult to single out the most important parameter that controls the selectivity toward direct synthesis of H₂O₂. Herein, support‐free monometallic Pd nanocrystals with different shapes and surface strains are used to investigate their impacts on the decomposition kinetics of H₂O₂. The kinetics are analyzed by tracking the concentration of the remaining H₂O₂using infrared spectroscopy. The data indicates that both surface structure and strain affect the decomposition kinetics of H₂O₂, but their impacts are inferior to that caused by Br⁻, a surface capping agent for the Pd{100} facets. The experimental results are consistent with the trend obtained through density functional theory calculations. This work helps shed light on the development of Pd‐based catalysts for the direct synthesis of H₂O₂by offering strategies to mitigate the decomposition of the desired product.

Photocatalytic hydrogen generation by electrospun TiO₂nanofibers decorated with various co-catalysts (Pt₂Pd, PtCu, Cu, Pt, Pd) was explored.

Devising syntheses capable of precisely manipulating matter on the nanoscale is central to many areas of research. The underlying motivation is fueled by the fact that at the nanometer scale, the property has a strong correlation with the structure. One such nanostructure that has accrued much attention is the dimer—a structure composed of two colloidal particles separated by a small gap. This Focus Review discusses how colloidal stability can be strategically manipulated to induce dimerization, together with effective purification steps to further improve yields. We conclude the article by providing representative examples for how dimers composed of plasmonic nanoparticles leads to structures with tunable optical properties and strong electric near‐fields, ideal for application in surface‐enhanced Raman spectroscopy.

This work demonstrates a new strategy for controlling the evolution of twin defects in metal nanocrystals by simply following thermodynamic principles. With Ag nanocrystals supported on amorphous SiO₂as a typical example, we establish that twin defects can be rationally generated by equilibrating nanoparticles of different sizes through heating and then cooling. We validate that Ag nanocrystals with icosahedral, decahedral, and single‐crystal structures are favored at sizes below 7 nm, between 7 and 11 nm, and greater than 11 nm, respectively. This trend is then rationalized by computational studies based on density functional theory and molecular dynamics, which show that the excess free energy for the three equilibrium structures correlate strongly with particle size. This work not only highlights the importance of thermodynamic control but also adds another synthetic method to the ever‐expanding toolbox used for generating metal nanocrystals with desired properties.