Artificial photosynthetic assemblies constructed by the self-assembly of synthetic building blocks for enhanced photocatalytic hydrogen evolution

Abstract

An artificial photosynthetic assemblies (APA) of hollow-rod structure was successfully constructed by using synthetic building blocks to mimic the structure and function of natural photosynthetic bacteria. The APA was formed...

Assembling CdSe Quantum Dots into Polymeric Micelles Formed by a Polyethylenimine-Based Amphiphilic Polymer to Enhance Efficiency and Selectivity of CO2-to-CO Photoreduction in Water

“…After mixing of CdSe QDs and PEI-LA-2 solutions, the ξ potential and pH value of the CdSe@PEI-LA-2 solution ([CdSe] = 0.10 mg mL –1 and [ PEI-LA-2 ] = 2.00 mg mL –1 ) change to 11.5 mV and 7.06, respectively. The second derivative IR spectra show that the CO stretching vibration peak of the carboxyl groups of CdSe QDs in the CdSe@PEI-LA-2 assemblies shifts from 1643 cm –1 in an acidic solution (pH 5.0) to 1653 cm –1 in a basic solution (pH 9.0), while analogous changes in the N–H bending vibration peak in PEI-LA-2 from 1536 cm –1 in an acidic solution to 1561 cm –1 in a basic solution were recorded (Figure c). , Another interaction between CdSe QDs and PEI-LA-2 is surface coordination of the terminal −NH 2 group in PEI-LA-2 to surface Cd atoms in the QDs, which is evidenced from XPS measurements (Figure d) and our previous report . Two distinct peaks at 404.83 eV (Cd 3d 5/2 ) and 411.58 eV (Cd 3d 3/2 ) in the Cd 3d spectrum of CdSe QDs negatively shift in the presence of PEI-LA-2 or PEI, , indicating that coordination between Cd atoms and amino groups in PEI-LA-2 or PEI occurs.…”

“…The amphiphilic polymer PEI-LA containing hydrophilic amino groups and hydrophobic C 12 alkyl chains was synthesized by grafting LA onto hyperbranched PEI (M w = 60k) via amide groups (Experimental Section). 20 The PEI-LA as a white powder was characterized by 1 H NMR, FT-IR, and UV−Vis spectroscopies. In addition to signals of the alkyl skeleton of PEI at δ = 3.00−2.30 ppm, the 1 H NMR spectra of PEI-LA show a group of signals at δ = 2.12, 1.50, 1.23, and 0.85 ppm (Supporting Information, Figure S1), which are attributed to the long alkyl chains.…”

Interface-Engineered Ni-Coated CdTe Heterojunction Photocathode for Enhanced Photoelectrochemical Hydrogen Evolution

“…Solar-driven PEC water splitting provides a sustainable and storable energy source assisting in reducing society’s dependence on fossil fuels, consequently reducing CO 2 emissions and improving the ecological environment. − The key part of the PEC water splitting cell is the semiconductor photoelectrode, which is required to efficiently absorb and convert solar energy into electrons and holes. Although much research effort has been dedicated to the investigation of different semiconductor photoelectrodes, − it is still very challenging to develop a low-cost, robust, and highly efficient semiconductor photoelectrode to enable a practical solar hydrogen production. , …”

Water-Phase Lateral Interconnecting Quantum Dots as Free-Floating 2D Film Assembled by Hydrogen-Bonding Interactions to Acquire Excellent Electrocatalytic Activity

“…On the other side, the spontaneous formation of nanoparticle (NP)-based superstructures that could potentially fabricate nanomaterials with fascinating properties has always been a goal of material science. − However, the fabrication of artificial self-assembled ultrathin films currently depends too much on the use of a solid surface, , block copolymers, or two-phase interfaces − that act as templates and give dimension-restrictive cues, just like in the well-known Langmuir-Blodget and traditional drying-mediated processes . Template-free supramolecular self-assembly of nanoparticles in two orthogonal directions is still a challenge, because of the unquenchable random self-stacking of NPs and the difficulty in controlling the anisotropic driving force to sustain the 2D arrangements in solution.…”