Photocatalytic Hydrogen Evolution Based on Efficient Energy and Electron Transfers in Donor–Bridge–Acceptor Multibranched‐Porphyrin‐Functionalized Platinum Nanocomposites

Abstract

Two donor–bridge–acceptor conjugates (5,10,15,20‐tetrakis[4‐(N,N‐diphenylaminobenzoate)phenyl] porphyrin (TPPZ) and 5,10,15,20‐tetrakis[4‐(N,N‐diphenylaminostyryl)phenyl] porphyrin (TPPX)) were covalently linked to triphenylamine (TPA) at the meso‐position of porphyrin ring. The triphenylamine entities were expected to act as energy donors and the porphyrins to act as an energy acceptor. In this paper, we report on the synthesis of these multibranched‐porphyrin‐functionalized Pt nanocomposites. The conjugates used here not only served as a stabilizer to prevent agglomeration of Pt nanoparticles, but also as a light‐harvesting photosensitizer. The occurrence of photoinduced electron‐transfer processes was confirmed by time‐resolved fluorescence and photoelectrochemical spectral measurements. The different efficiencies for energy and electron transfer in the two multibranched porphyrins and the functionalized Pt nanocomposites were attributed to diverse covalent linkages. Moreover, in the reduction of water to produce H2, the photocatalytic activity of the Pt nanocomposite functionalized by TPPX, in which the triphenylamine and porphyrin moieties are bonded through an ethylene bridge, was much higher than that of the platinum nanocomposite functionalized by TPPZ, in which the two moieties are bonded through an ester. This investigation demonstrates the fundamental advantages of constructing donor–bridge–acceptor conjugates as highly efficient photosensitizers based on efficient energy and electron transfer.

Two dimensional MoS2/graphene composites as promising supports for Pt electrocatalysts towards methanol oxidation

“…The Pt 4f displays that a doublet peak originating from the spin orbital splitting of the 4f 7/2 and 4f 5/2 states are centred at 71.0 and 74.4 eV. These results agree well with the values for metallic Pt [28], revealing that the metallic Pt nanoparticles were deposited on the surface of the MoS 2 or MoS 2 /RGO sheets.…”

Spin–Orbit Charge‐Transfer Intersystem Crossing in Anthracene–Perylenebisimide Compact Electron Donor–Acceptor Dyads and Triads and Photochemical Dianion Formation

“…The triplet excited state plays an important role in photoredox catalytic organic reactions, [1][2][3][4][5][6] phosphorescence-based lightemitting diodes, [7] H 2 productionb yp hotocatalytic water splitting, [8][9][10][11][12][13] photodynamic therapy, [14][15][16][17] and triplet-triplet annihilation upconversion. [18][19][20][21][22][23][24][25] The triplet state of organic com-poundsi sp opulated by intersystem crossing (ISC), [26] which is as pin-forbidden process.…”

Rationally Designed Functional Ni2P Nanoparticles as Co–Catalyst Modified CdS@g‐C3N4 Heterojunction for Efficient Photocatalytic Hydrogen Evolution

“…For the purpose of further understand the photo‐generated charge transfer and its quenching mechanism of the samples, the fluorescence lifetime was measured by transient fluorescence spectroscopy combining with the method of third order index fitting and the results summarized in Table S1. We used follow equation to calculate the mean fluorescence lifetimes of each sample , …”