Achieving metal-like catalysis from semiconductor for on-surface synthesis.

Free of posttransfer, on-surface synthesis (OSS) of single-atomic-layer nanostructures directly on semiconductors holds considerable potential for next-generation devices. However, due to the high diffusion barrier and abundant defects on semiconductor surfaces, extended and well-defined OSS on semiconductors has major difficulty. Furthermore, given semiconductors' limited thermal catalytic activity, initiating high-barrier reactions remains a significant challenge.

Real-Time Imaging of On-Surface Ullmann Polymerization Reveals an Inhibiting Effect of Adatoms.

Ullmann coupling is a widely used reaction for the on-surface growth of low-dimensional carbon nanomaterials. The irreversible nature of this reaction prevents the "self-healing" of defects, and a detailed knowledge of its mechanism is therefore essential to enable the growth of extended ordered structures. However, the dynamics of the Ullmann polymerization remain largely unexplored, as coupling events occur on a timescale faster than conventional scanning probe microscopy imaging frequencies.

Dual Aliovalent Dopants Cu, Mn Engineered Eco-Friendly QDs for Ultra-Stable Anti-Counterfeiting.

Doping in semiconductor quantum dots (QDs) using optically active dopants tailors their optical, electronic, and magnetic properties beyond what is achieved by controlling size, shape, and composition. Herein, we synergistically modulated the optical properties of eco-friendly ZnInSe/ZnSe core/shell QDs by incorporating Cu-doping and Mn-alloying into their core and shell to investigate their use in anti-counterfeiting and information encryption. The engineered "Cu:ZnInSe/Mn:ZnSe" core/shell QDs exhibit an intense bright orange photoluminescence (PL) emission centered at 606 nm, with better color purity than the undoped and individually doped core/shell QDs.

Effect of aromatic substituents on the H-bonded assembly of diketopyrrolopyrroles at solid-liquid interfaces.

Hydrogen-bonded (H-bonded) self-assembly is a suitable approach for tailoring the solid-state packing and properties of organic semiconductors. Here we studied the H-bonded self-assembly of an important class of organic semiconductors, diketopyrrolopyrrole (DPP) derivatives, diselenophenylDPP (DSeDPP), dithiazolylDPP (DTzDPP), and dithienothiophenylDPP (DTTDPP), at solid-liquid interfaces using scanning tunneling microscopy (STM) and density functional theory (DFT). At the 1-octanoic acid/highly ordered pyrolytic graphite (HOPG) interface, DSeDPP and DTzDPP either co-assemble with the solvent H-bonding between lactam and carboxyl groups or form homoassemblies through H-bonding between the lactam groups.

Heavy-Metal-Free Colloidal Quantum Dots: Progress and Opportunities in Solar Technologies.

Colloidal quantum dots (QDs) hold great promise as building blocks in solar technologies owing to their remarkable photostability and adjustable properties through the rationale involving size, atomic composition of core and shell, shapes, and surface states. However, most high-performing QDs in solar conversion contain hazardous metal elements, including Cd and Pb, posing significant environmental risks. Here, a comprehensive review of heavy-metal-free colloidal QDs for solar technologies, including photovoltaic (PV) devices, solar-to-chemical fuel conversion, and luminescent solar concentrators (LSCs), is presented.