Tuning the Catalytic Activity of Bifunctional Cobalt Boride Nanoflakes for Overall Water Splitting over a Wide pH Range

Abstract

The world is in the process of transitioning toward a more sustainable energy future, with green hydrogen considered an attractive energy vector that can replace fossil fuel consumption, meeting global energy demands. To date, the most advanced method to produce green hydrogen is through water electrolysis using the residual supply of renewable energy. The current state-of-the-art catalysts used in electrolyzers are platinum-based metals and ruthenium/iridium oxides. The scarceness of these elements, combined with their high price, make these catalysts not economically viable for large-scale production of hydrogen through water electrolysis. This study presents cobalt boride nanoflakes as materials to be used in both the anode and the cathode of an electrolyzer for electrochemical water splitting over a wide pH range. The cobalt boride nanoflakes were synthesized by the chemical reduction of CoCl2 using NaBH4 at three different concentrations to obtain CoB and Co2B nanoflakes. CoB nanoflakes exhibited both a higher specific surface area and greatest disparity in charge between B and Co, in comparison to Co2B. It was demonstrated that by tuning the properties of the cobalt boride nanoflakes, higher catalytic activities for both the hydrogen and oxygen evolution reaction can be achieved, showing good overall stability.

Engineering 2D nickel boride/borate amorphous/amorphous heterostructures for electrocatalytic water splitting and magnetism

“…5b) exhibits two peaks, with the first located at ∼192 eV assigned to boron nickel interactions (B–N), 21,34,39 and the second at ∼198.9 eV related to boron oxo species. 9,10,40 On the other hand, for the NiB/NiBO 3 -II and NiB/NiBO 3 -III samples, the second boron peak of their B 1s spectra (Fig. 5e and h) was further deconvoluted to two more peaks, centred at ∼198.2 eV and ∼199.8 eV, indicating that the extra available boron during synthesis was further oxidised to B 2 O 3 .…”

“…1–3 This significant traction of 2D nanomaterials can be attributed to their outstanding properties like their high specific surface area, significant carrier mobility, 4,5 high electrical conductivity, 6,7 and most importantly, materials versatility since they can be crystalline or amorphous, as well as organic or inorganic. 8 Despite these outstanding properties, 2D nanomaterials still need additional tuning in order to accommodate the needs of their potential application, such as catalysis, 9,10 energy storage 11 or optoelectronics. 12 This tuning can be easily achieved by assembling different 2D nanomaterials into heterostructures, in other words, creating a hybrid system that presents an interface between two materials.…”

CDs “inserted” abundant FeB-based electrode via “local photothermal effect” strategy toward efficient overall seawater splitting

“…Around this problem, a series of Fe–B, Fe–S, Fe–P and other catalytic materials have been reported; 7,8 Ghafar et al reviewed the research progress of electrocatalytic water splitting of metal borate. 9 Among them, Fe–B catalytic materials have achieved the advantages of efficient catalysis, mild reaction conditions, non-toxicity, and few by-products and have received great attention in the field of efficient water splitting. 10 Gao et al introduced carbon nanotubes (CNTs), prepared CNTs modified with FeB nanoparticles (expressed as FeB/CNTs) into the MgH 2 system by cyclohexane (CYH) wet grinding, and the results showed that both CYH and the addition of dopants (CNT, FeB or FeB/CNT) could improve the catalytic effect.…”

Exploring the Magnetic and Electrocatalytic Properties of Amorphous MnB Nanoflakes

“…They have high melting points and hardness, they are thermodynamically stable, they have excellent electric conductivity and superconductivity, and they are catalytically active and corrosive resistant [ 1 , 2 , 3 , 4 ]. Hence, they are extensively used in sensing, electronics, catalysis, energy harvesting, ion transport, superconductivity, hydrogen generation, and storage [ 5 , 6 , 7 , 8 , 9 ]. Their stoichiometry varies from compounds with low a boron content similar to metal mono-borides (MB) to compounds with a very high boron content (MB 99 ).…”