Towards Solar Factories: Prospects of Solar‐to‐Chemical Energy Conversion using Colloidal Semiconductor Photosynthetic Systems

Abstract

Solar-to-chemical (STC) energy conversion is the fundamental process that nurtures Earth's ecosystem, fixing the inexhaustible solar resource into chemical bonds. Photochemical synthesis endowsp lants with the primarys ubstances for their development;l ikewise, an artificial mimic of natural systems has long sought to support human civilization in as ustainable way.I ntensive efforts have demonstrated light-triggered productiono fd ifferent solar fuels, such as H 2 ,C O, CH 4 and NH 3 , while research on oxidative half-reactions has built up from O 2 generation to organic synthesis, waste degradation and photoreforming. Nevertheless, while extensive utilization of the radiant chemical potentialt op romote am anifold of endergonic processesi st he common thread of such research, exploration of the chemical space is fragmented by the lack of ac ommon languagea cross different scientific disciplines. Focusing on colloidal semiconductor materials, this Viewpoint discusses an inclusive protocol for the discoverya nd assessment of STC redox reactions, aiming to establish photon-to-molecule conversion as the ultimate paradigm beyondf ossil energy exploitation.

Rationalizing Photo‐Triggered Hydrogen Evolution Using Polypyridine Cobalt Complexes: Substituent Effects on Hexadentate Chelating Ligands

“…Quantum yield values were estimated to be 3.5, 10.1, 3.9, 11.3, and 8.8 % for C1 – C4 and C0 , respectively. In order to compare the photochemical data on a more quantitative basis, we should first stress the main differences between the figure‐of‐merits we have estimated in the light‐driven hydrogen evolution experiments and their actual role in the definition of the photochemical performance [22] . The maximum TON is indeed a metric of the stability of the photocatalytic system, whereas the quantum yield (and under the present experimental conditions also the maximum TOF) is a suitable parameter that accounts for the efficiency of the light‐to‐hydrogen conversion process.…”

Electrocatalytic hydrogen evolution using hybrid electrodes based on single-walled carbon nanohorns and cobalt(ii) polypyridine complexes

“…The production of hydrogen from water splitting represents one of the most relevant, although challenging processes for the generation of clean fuels. [1][2][3][4][5] During the last years, several efforts have been made towards the development of efficient catalysts with the potential ability of competing with and possibly replacing the expensive and rare platinum metal. 6,7 In this respect, particular attention has been paid to the development of earth abundant molecular catalysts, whose structures and functions take inspiration from those of the active sites of natural hydrogenases.…”

Beyond Water Oxidation: Hybrid, Molecular-Based Photoanodes for the Production of Value-Added Organics

“…Conversely, the coupling of proton reduction with photoredox catalysis aims at obtaining value-added organic products and fine chemicals starting from pure compounds such as alcohols, acids, aldehydes, and amines. Compared with photoreforming, photoredox catalysis requires pure starting materials, which might somehow reduce the cost-effectiveness of the process ( Lhermitte and Sivula, 2019 ; Agosti et al, 2020 ; Tang and Sun, 2020 ; Qi et al, 2021 ). The vast majority of the systems reported so far both for photoreforming and photoredox catalysis are based on semiconductor nanoparticles, mostly used as suspensions.…”