The alkaline direct alcohol fuel cell (ADAFC) is an environmentally friendly electrochemical energy source that can drive a plethora of consumer and portable electronics. Research in ADAFCs has continued to attract major attention due to their several advantages over conventional proton-exchange membrane fuel cells (PEMFC); these include the emergence of anion-exchange membranes (AEM), easy handling of liquid alcohol fuels compared to hydrogen, higher volumetric energy densities of alcohols compared to hydrogen, enhanced reaction kinetics of alcohols and oxygen reduction reaction in alkaline media. Further developments in this field are dependent on improving the performance of nanostructured electrocatalysts and AEMs. This review is an overview of some notable advances made in recent years. Importantly, it provides an excellent insight into the fundamental principles that allow for the intelligent design and synthesis of non-precious metal nanostructured electrocatalysts for the cathode and anode reactions of ADAFCs. This review is an attempt to find answers to questions such as “Why should I use a particular catalyst for the ADAFC?”, “What are the underlying principles that must inform my choice in designing such a catalyst?”, and “What synthesis method(s) or catalyst supports should be considered to prepare catalysts with the appropriate physicochemical properties for high-performance?” The knowledge provided in this review can be applied not only to ADAFCs, but also to several other electrocatalytic systems (such as various other fuel cell systems, electrochemical sensors, and metal–air batteries).

The energy storage performance of one of the lightest-known MXenes, Ti₂CT_x (MX) combined with carbon nanospheres (CNS) has been investigated as a symmetric electrode system in an aqueous electrolyte (1 M Li₂SO₄). The energy storage properties were interrogated using cyclic voltammetry (CV), galvanostatic cycling with potential limitation (GCPL), electrochemical impedance spectroscopy (EIS) and voltage-holding tests. The combined material (MX/CNS) demonstrated a higher specific capacity compared to each of the individual components. The material was fabricated with relatively high and low mass loadings, assembled into a symmetric device and performance compared. Specific capacitance, specific power and specific energy for the lower electrode mass loading of 180 F⋅g⁻¹, 37.6 kW⋅kg⁻¹ and 14.1 W⋅h⋅kg⁻¹ were all higher than 86 F⋅g⁻¹, 20.1 kW⋅kg⁻¹ and 6.7 W⋅h⋅kg⁻¹ for the higher mass loading. A wide voltage window of 1.5 V was obtained, but with limited long-term cycling behavior, suggesting the need for future improvement. Mathematical modelling and simulation of the supercapacitor showed good correlation with the experimental results, validating the model. The results reveal the potential of the Ti₂CT_x to be employed as a viable energy storage system for lightweight applications.

Recently reported ruthenium (Ru)-based catalysts for the oxygen evolution reaction (OER) falling in the Ru metal and Ru compound subclasses are summarized with special emphasis being given to a discussion of activity/stability-enhancing strategies.

The supercapacitive properties of nickel(II) tetraaminophthalocyanine (NiTAPc)/multi-walled carbon nanotube (MWCNT) nanocomposite films have been interrogated for the first time and found to possess a maximum specific capacitance of 981 ± 57 F g⁻¹ (200 ± 12 mF cm⁻²), a maximum power density of 700 ± 1 Wkg⁻¹, a maximum specific energy of 134 ± 8 Wh kg⁻¹ and excellent stability of over 1500 charge-discharge continuous cycling. Impedimetric study proves that most of the stored energy of the MWCNT-NiTAPc nanocomposite can be accessible at high frequency (720 Hz). When compared to MWCNTs modified with unsubstituted nickel(II) phthalocyanine (MWCNT-NiPc) or nickel(II) tetra-tert-butylphthalocyanine (MWCNT-tBuNiPc), MWCNT-NiTAPc exhibited superior supercapacitive behaviour, possibly due to the influence of nitrogen-containing groups on the phthalocyanine rings.

Flower-like MoS₂modified with carbon nanospheres (CNS) displays energy-storage capability when used as an aqueous symmetric pseudocapacitor.

We present a facile method for the rational design of highly exfoliated two-dimensional Ti ₃ C ₂ T _x nanosheets (T _x = O, OH, and F) doped with Cu (Cu/Ti ₃ C ₂ T _x ) for electrochemical CO ₂ reduction to formic acid at low Cu content of ∼1 wt%.