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Propylsulfonic acid derivatised SBA-15 catalysts have been prepared by post modification of SBA-15 with mercaptopropyltrimethoxysilane (MPTS) for the upgrading of a model pyrolysis bio-oil via acetic acid esterification with benzyl alcohol in toluene. Acetic acid conversion and the rate of benzyl acetate production was proportional to the PrSO 3 H surface coverage, reaching a maximum for a saturation adlayer. Turnover frequencies for esterification increase with sulfonic acid surface density, suggesting a cooperative effect of adjacent PrSO 3 H groups. Maximal acetic acid conversion was attained under acid-rich conditions with aromatic alcohols, outperforming Amberlyst or USY zeolites, with additional excellent water tolerance.

A bimetallic cobalt molybdenum sulfide (Co0.5Mo0.5Sx) material was studied as candidate electrocatalyst to replace platinum-based cathode for HER reaction in alkaline media. The Co0.5Mo0.5Sx was obtained from a hydrothermal synthesis methodology employing sodium diethyldithiocarbamate as sulfurizing agent, a non-conventional compound. The recovered sulfide material was physicochemically characterized by XRD, Raman spectroscopy, TEM and XPS measurements. Analogous monometallic sulfides were also synthesized to compare their HER activities to that of Co0.5Mo0.5Sx. Such electrochemical characterization was performed by the application of polarization and EIS analyzes in 1 M KOH. An evident synergistic effect emerged in the bimetallic sulfide and it was associated with the design of a catalyst less susceptible to air-oxidation added to the roles performed by cobalt- and molybdenum-based species in the HER mechanism. Finally, a physical mixture of Co0.5Mo0.5Sx and Carbon Vulcan was prepared aiming to enhance the electronic conductivity of the electrode. As result, an overpotential of 131 mV was requested to achieve −10 mA cm−2. In addition, to achieve −200 mA cm−2, this electrode only needed an overpotential 66 mV higher than the one necessary for the benchmarking 40% Pt/C electrocatalyst.

Foresee advanced and innovative strategies is a key approach and constitutes a cornerstone for accessing clean, affordable, and reliable energy to satisfy the world's increasing prosperity and economic growth. To this end, hydrogen energy technologies parade as promising sustainable solutions to the looming energy crisis at either the small or large industrial scale, which will enable to reduce significantly our dependence on conventional energy sources based on fossil fuels without increasing atmospheric CO2 levels. Water electrolysis with renewable energy is one of the best solutions to produce hydrogen without COx (CO and CO2) emissions. However, the practical realization of this elegant opportunity of paramount importance is facing several challenges, among which are: (i) the efficient design of cathode and anode catalytic materials exhibiting improved intrinsic and durable activity; (ii) the scale‐up of the system for the large‐scale hydrogen production through the electrochemical water splitting. This review puts these opportunities and challenges into a broad context, discusses the recent research and technological advances, and finally provides several pathways and guidelines that could inspire the development of groundbreaking electrochemical devices for hydrogen production. It also points out the materials design and preparation for the efficient electrochemical production of the molecular hydrogen in acidic and alkaline environments, from a simple electrolytic solution to the water splitting reaction, which is also considered in the process. Furthermore, the main technology keys for designing a reliable electrochemical system will be noticed.