Efficient photocatalytic hydrogen evolution without an electron mediator using a simple electron donor–acceptor dyad

2007 ◽  
Vol 9 (12) ◽  
pp. 1487-1492 ◽  
Author(s):  
Hiroaki Kotani ◽  
Toshiya Ono ◽  
Kei Ohkubo ◽  
Shunichi Fukuzumi
2012 ◽  
Vol 65 (12) ◽  
pp. 1573 ◽  
Author(s):  
Yusuke Yamada ◽  
Kentaro Yano ◽  
Shunichi Fukuzumi

Photocatalytic hydrogen evolution has been performed by photoirradiation (λ > 420 nm) of a mixed solution of a phthalate buffer and acetonitrile (MeCN) (1 : 1 (v/v)) containing EDTA disodium salt (EDTA), [RuII(bpy)3]2+ (bpy = 2,2′-bipyiridine), 9-phenyl-10-methylacridinium ion (Ph–Acr+–Me), and Pt nanoparticles (PtNPs) as a sacrificial electron donor, a photosensitiser, an electron mediator, and a hydrogen-evolution catalyst, respectively. The hydrogen-evolution rate of the reaction system employing Ph–Acr+–Me as an electron mediator was more than 10 times higher than that employing a conventional electron mediator of methyl viologen. In this reaction system, ruthenium nanoparticles (RuNPs) also act as a hydrogen-evolution catalyst as well as the PtNPs. The immobilization of the efficient electron mediator on the surface of a hydrogen-evolution catalyst is expected to enhance the hydrogen-evolution rate. The methyl group of Ph–Acr+–Me was chemically modified with a carboxy group (Ph–Acr+–CH2COOH) to interact with metal oxide surfaces. In the photocatalytic hydrogen-evolution system using Ph–Acr+–CH2COOH and Pt-loaded ruthenium oxide nanoparticles (Pt/RuO2NPs) as electron donor and hydrogen-evolution catalyst, respectively, the hydrogen-evolution rate was 1.5–2 times faster than the reaction system using Ph–Acr+–Me as an electron mediator. On the other hand, no enhancement in the hydrogen-evolution rate was observed in the reaction system using Ph–Acr+–CH2COOH with PtNPs. Thus, the enhancement of hydrogen-evolution rate originated from the favourable interaction between Ph–Acr+–CH2COOH and RuO2NPs. These results suggest that the use of Ph–Acr+–Me as an electron mediator enables the photocatalytic hydrogen evolution using PtNPs and RuNPs as hydrogen-evolution catalysts, and the chemical modification of Ph–Acr+–Me with a carboxy group paves the way to utilise a supporting catalyst, Pt loaded on a metal oxide, as a hydrogen-evolution catalyst.


Author(s):  
Haofan Yang ◽  
Xiaobo Li ◽  
Reiner Sebastian Sprick ◽  
Andrew I. Cooper

A library of 237 organic binary/ternary nanohybrids consisting of conjugated polymers donors and both fullerene and non-fullerene molecular acceptors was prepared and screened for sacrificial photocatalytic hydrogen evolution. These donor-acceptor nanohybrids (DANHs) showed significantly enhanced hydrogen evolution rates compared with the parent donor or acceptor compounds. DANHs of <a></a><a>a polycarbazole</a>-based donor combined with a methanofullerene acceptor (PCDTBT/PC<sub>60</sub>BM) showed a high hydrogen evolution rate of 105.2 mmol g<sup>-1</sup> h<sup>-1</sup> under visible light (λ > 420 nm). This DANH photocatalyst produced 5.9 times more hydrogen than a sulfone-containing polymer (P10) under the same conditions, which is one of the most efficient organic photocatalysts reported so far. An apparent quantum yield of hydrogen evolution of 3.0 % at 595 nm was measured for this DANH. The photocatalytic activity of the DANHs, which in optimized cases reached 179.0 mmol g<sup>-1</sup> h<sup>-1</sup>, is attributed to efficient charge transfer at the polymer donor/molecular acceptor interface. We also show that ternary donor<sub>A</sub>-donor<sub>B</sub>-acceptor nanohybrids can give higher activities than binary donor-acceptor hybrids in some cases.


2019 ◽  
Vol 10 (47) ◽  
pp. 6473-6480 ◽  
Author(s):  
Ruimin Diao ◽  
Haonan Ye ◽  
Zhicheng Yang ◽  
Shicong Zhang ◽  
Kangyi Kong ◽  
...  

The hydrogen evolution rate of PDPP3B-O4 with butoxy chain was 5.53 mmol h−1 g−1 with 1% Pt loading (λ > 400 nm), increased 110 times than PDPP3B-C8 with octyl chain due to wider absorption spectrum and better wettability via side chain engineering.


2016 ◽  
Vol 14 (1) ◽  
pp. 393-403 ◽  
Author(s):  
Eugenia Koutsouri ◽  
Christiana A. Mitsopoulou

AbstractHerein, we report on the homogeneous photocatalytic evolution of hydrogen by using as reductive catalysts the prismatic symmetric tris – dithiolene complexes of the tungsten, namely [W{S2C2(Ph)2}3] (1) and its monoanion [W{S2C2(Ph)2}3](TBA) (2). Complex 2 is fully characterized by elemental analysis, ESI-MS, IR, UV-Vis and fluorescence spectrophotometry as well as cyclic voltammetry. The photocatalytic system consists of [ReBr(CO)3(bpy)] as a photosensitizer, triethanolamine as a sacrificial electron donor and acetic acid as the proton source. Although the activity of the photocatalytic system is rather small (TON=18), it indicates that the homoleptic tris dithiolene complexes can act as proton reductive catalysts with their monoanion form to be more active in accordance with the findings for the bis - dithiolene complexes.


2015 ◽  
Vol 5 (1) ◽  
pp. 428-437 ◽  
Author(s):  
Yusuke Yamada ◽  
Akifumi Nomura ◽  
Hideyuki Tadokoro ◽  
Shunichi Fukuzumi

A Pt catalyst was closely located to an organic photosensitiser on a negatively charged semiconductor for efficient photocatalytic H2 evolution.


2019 ◽  
Author(s):  
Haofan Yang ◽  
Xiaobo Li ◽  
Reiner Sebastian Sprick ◽  
Andrew I. Cooper

A library of 237 organic binary/ternary nanohybrids consisting of conjugated polymers donors and both fullerene and non-fullerene molecular acceptors was prepared and screened for sacrificial photocatalytic hydrogen evolution. These donor-acceptor nanohybrids (DANHs) showed significantly enhanced hydrogen evolution rates compared with the parent donor or acceptor compounds. DANHs of <a></a><a>a polycarbazole</a>-based donor combined with a methanofullerene acceptor (PCDTBT/PC<sub>60</sub>BM) showed a high hydrogen evolution rate of 105.2 mmol g<sup>-1</sup> h<sup>-1</sup> under visible light (λ > 420 nm). This DANH photocatalyst produced 5.9 times more hydrogen than a sulfone-containing polymer (P10) under the same conditions, which is one of the most efficient organic photocatalysts reported so far. An apparent quantum yield of hydrogen evolution of 3.0 % at 595 nm was measured for this DANH. The photocatalytic activity of the DANHs, which in optimized cases reached 179.0 mmol g<sup>-1</sup> h<sup>-1</sup>, is attributed to efficient charge transfer at the polymer donor/molecular acceptor interface. We also show that ternary donor<sub>A</sub>-donor<sub>B</sub>-acceptor nanohybrids can give higher activities than binary donor-acceptor hybrids in some cases.


Sign in / Sign up

Export Citation Format

Share Document