Please use this identifier to cite or link to this item: https://hdl.handle.net/10356/103691
Title: Visible light driven hydrogen evolution by molecular nickel catalysts with time-resolved spectroscopic and DFT insights
Authors: Ho, Xian Liang
Shao, Haiyan
Ng, Yik Yie
Ganguly, Rakesh
Lu, Yunpeng
Soo, Han Sen
Keywords: Science::Chemistry
Issue Date: 2019
Source: Ho, X. L., Shao, H., Ng, Y. Y., Ganguly, R., Lu, Y., & Soo, H. S. (2019). Visible light driven hydrogen evolution by molecular nickel catalysts with time-resolved spectroscopic and DFT insights. Inorganic Chemistry, 58(2), 1469-1480. doi:10.1021/acs.inorgchem.8b03003
Project: M4081012 
RG 12/16 
RG 13/17 
Journal: Inorganic Chemistry 
Series/Report no.: Inorganic Chemistry
Abstract: Hydrogen (H2) is a clean fuel that can potentially be a future solution for the storage of intermittent renewable energy. However, current H2 production is mainly dominated by the energy intensive steam reforming reaction, which consumes a fossil fuel, methane, and emits copious amounts of carbon dioxide as one of the byproducts. To address this challenge, we report a molecular catalyst that produces H2 from aqueous solutions, is composed of affordable, earth-abundant elements such as nickel, and has been incorporated into a system driven by visible light. Under optimized conditions, we observe a turnover number of 3880, among the best for photocatalytic H2 evolution with nickel complexes from water–methanol solutions. Through nanosecond transient absorption, electron paramagnetic resonance, and UV–vis spectroscopic measurements, and supported by density functional theory calculations, we report a detailed study of this photocatalytic H2 evolution cycle. We demonstrate that a one-electron reduced, predominantly ligand-centered, reactive Ni intermediate can be accessed under visible light irradiation using triethylamine as the sacrificial electron donor and reductive quencher of the initial photosensitizer excited state. In addition, the computational calculations suggest that the second coordination sphere ether arms can enhance the catalytic activity by promoting proton relay, similar to the mechanism among [FeFe] hydrogenases in nature. Our study can form the basis for future development of H2 evolution molecular catalysts that incorporate both ligand redox noninnocence and alternative second coordination sphere effects in artificial photosynthetic systems driven by visible light.
URI: https://hdl.handle.net/10356/103691
http://hdl.handle.net/10220/47667
ISSN: 0020-1669
DOI: 10.1021/acs.inorgchem.8b03003
Schools: School of Physical and Mathematical Sciences 
Rights: This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://doi.org/10.1021/acs.inorgchem.8b03003.
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:SPMS Journal Articles

SCOPUSTM   
Citations 20

16
Updated on Mar 6, 2024

Web of ScienceTM
Citations 20

14
Updated on Oct 28, 2023

Page view(s) 50

569
Updated on Mar 18, 2024

Download(s) 50

100
Updated on Mar 18, 2024

Google ScholarTM

Check

Altmetric


Plumx

Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.