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Visible‐light triggerable, stable, organic material‐based photocatalysts that can function in alkaline media without the necessity of sacrificial agent for hydrogen production are highly sought after. Here, we report a novel supramolecular photocatalyst that confers the aforementioned features. This supramolecular photocatalyst (TPP‐4CB7) is synthesized through the conjugation of monohydroxylated cucurbit(7)uril (CB7) hosts to a suitably substituted tetraphenyl porphyrin. Although TPP‐4CB7 by its own preforms as an efficient visible light triggered photocatalyst, the hydrogen production efficiency is significantly enhanced upon mixing with TiO2. The resulting nanocomposite (TPP‐CB‐TiO2@Pt) is observed to exhibit remarkable electrophotocatalytic activity under visible light and produces hydrogen (onset potential −10 mV, turn over frequency (TOF) 0.202 s−1, 24.5 mmol h−1 g−1) from water splitting without any significant degradation during four runs (5 h each) in alkaline media and in the absence of sacrificial agent. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of a new supramolecular polymeric network (PCN) assembled through crosslinking of propyl bromide substituted tetraphenyl porphyrin with perhydroxy-cucurbit [8]uril and its use in the electrocatalytic hydrogen evaluation reaction after loading with nickel and integrating with in situ -electrochemically reduced graphene oxide (ERGO). Electrode was prepared by first coating graphene oxide on the FTO substrate followed by layering the nickel loaded PCN and finally by applying an appropriate voltage to reduce the graphene oxide in situ electrochemical reaction. The loading of nickel cocatalyst into PCN together with the integration of ERGO layer substantially improved its HER efficiency. Effect of various concentrations of Ni and GO on the HER activity of the developed electrocatalyst were investigated. Therein, ERGO 1 /Ni 2 @PCN catalyst containing 41% Ni and 50% GO (with respect to PCN) with only one layer of each component demonstrated excellent HER activity and stability with low onset and overpotentials of −20 mV, η@10 mA cm−2 of −360 mV, respectively, and remarkable hydrogen generation rate of 27.5 mmol h−1 g−1 in 1 M KOH. This noble-metal-free catalytic system is simple yet highly promising for the efficient hydrogen evolution reaction from water splitting. [Display omitted] • Cross-linked supramolecular polymeric network (PCN) for electrocatalytic HER. • Synthesis of PCN through crosslinking of porphyrin with perhydroxy-cucurbit [8]uril. • HER electrocatalyst based on in situ -ERGO layer integrated with Ni-loaded PCN. • Excellent HER activity and stability in 1 M KOH with high H 2 generation rate. [ABSTRACT FROM AUTHOR]

Front Cover: Novel Supramolecular Photocatalyst Based on Conjugation of Cucurbit[7]uril to Non-Metallated Porphyrin for Electrophotocatalytic Hydrogen Generation from Water Splitting (ChemCatChem 13/2019) B The Front Cover b shows solar energy promoted photoelectrocatalytic water splitting for hydrogen generation using a supramolecular photocatalyst. In their Communication, Dönüs Tuncel and co-workers synthesize a novel, visible light triggerable, stable supramolecular photocatalyst based on conjugation of cucurbit[7]uril to non-metallated porphyrin. [Extracted from the article]