Hyperbranched Conjugated Polymer Dots: The Enhanced Photocatalytic Activity for Visible Light-Driven Hydrogen Production

Abstract

Conjugated polymer (CP) aggregates with linear/cross-linked structures are widely reported as photocatalysts for hydrogen evolution reaction. For full disclosure of the relationship between the photocatalytic performance and structural features of the CP photocatalysts, homogeneous dispersion of these CPs in aqueous medium is necessary, which however is difficult to be achieved. Herein, we report several coassembled polymeric dots (Pdots) consisting of PEG 45 -b-PMMA 103 and CPs with various structural features. We found that the Pdots of hyperbranched soluble CP nanoparticles (SCPNs) exhibit a high H 2 evolution rate up to 840 μmol h −1 g −1 with no platinum or rhodium as a cocatalyst, superior to their analogues with the linear or cross-linked structure. A possible charge-transfer mechanism suggests that the photoelectrons directly mobilize to the surface of these single-particulate Pdots over three-dimensional skeleton and successfully avoid the ineffective intermolecular charge transfer, leading to the shortened diffusion path of photoelectrons and enhanced photolysis efficacy. We believe that the high dispersion stability (2 months), solution processability, and structural tunability of these Pdots with hyperbranched SCPNs would inspire further research on designing multicomponent photocatalysts for highly efficient visible light-driven hydrogen evolution reaction.

Co‐Assembly of Gd(III)‐Based Metallosurfactant and Conjugated Polymer Nanoparticles in Organosilica Cross‐Linked Block Copolymer Micelles for Highly Efficient MRI and Fluorescent Bimodal Imaging

“…[ 28 ] The fluorescent CPNs with bright red emission and size ranging between 10 and 20 nm (Figure S1, Supporting Information) were synthesized according to our recently published procedure. [ 25 ] They are highly soluble in a variety of organic solvents but insoluble in aqueous solutions.…”

“…Conjugated polymeric nanoparticles (CPNs) with high fluorescent intensity were chosen as the fluorescent dyes. [ 25 ] The self‐assembly of MS and F127 facilitate the encapsulation of the hydrophobic CPN fluorophore, and the crosslinking with MPTMS further endows the co‐assembly high micellar stability. The relaxivity of these nanoparticular CAs was synergistically enhanced by increasing q number with HAO‐type ligands and slowing down the tumbling rate of the Gd(III) complexes when embedded in the co‐assembly to achieve a record high value of 105.37 m m −1 s −1 (at 1.5 T).…”

Recent Advances in Visible‐Light‐Driven Hydrogen Evolution from Water using Polymer Photocatalysts

“…reported several co‐assembled Pdots combining PEG 45 ‐ b ‐PMMA 103 and soluble conjugated polymer nanoparticles (SCPNs) with a linear or cross‐linked structure. These Pdots exhibited a high HER of 841 μmol h −1 g −1 (λ>420 nm) under visible light and without Pt or Rh as a cocatalyst . In addition, they had important features such as solution processability, structural tunability, and high dispersion stability of nearly two months.…”

“…These Pdots exhibited a high HER of 841 μmol h À 1 g À 1 (λ > 420 nm) under visible light and without Pt or Rh as a cocatalyst. [95] In addition, they had important features such as solution processability, structural tunability, and high dispersion stability of nearly two months. [a] The results were concluded from references.…”

Effect of Supports and Promoters on the Performance of Ni‐Based Catalysts in Ethanol Steam Reforming

“…It is a highly efficient energy carrier (143 MJ kg -1 ) and it is mainly applied in fuel cells [3]. Green hydrogen can be produced from water electrolysis [4,5], photocatalytic methods [6,7], and from steam reforming of organic compounds such as methanol, ethanol, glycerol, acetic acid, acetol, and methane [8][9][10][11][12][13][14][15][16][17][18][19][20][21]. In the latter process, ethanol steam reforming (ESR) to produce hydrogen is a green and promising process because ethanol is a green material arising from biomass via conventional fermentation [22][23][24][25].…”