Ordering Nanostructures Enhances Electrocatalytic Reactions

Delving into structural ordering design and decoding the ordering–function relationship is a scientific as well as crucial topic given the current energy and environmental issues. Enhanced performance output hinges on the long-range ordering in nanostructured assemblies. Highly ordered patterned ensembles reasonably convey unexpected performance enhancement due to the uniformity and periodicity in the geomorphology and chemical environment of building blocks. Compared with random-oriented counterparts, aligned building blocks locally concentrate the reactant due to gathering along the same direction without local traffic disorder. The ordered architectures will ensure more continuous, fast mass transport in the reaction. The ever-growing push for sustainable energy has intensified research on catalytic science. Significant developments have been achieved in state-of-the-art catalyst design from the perspective of catalyst materials. Further promotion can be enabled when rethinking and redesigning the catalyst structure with long-range ordering rather than limited to the catalyst material design. Recently, ordered assembled nanostructures have shown advantages over their disordered counterparts in active site exposure and mass transfer. In this opinion article, we revisit and relate orderly assembly to entropy reduction. Recent advances in the engineering of ordered nanostructure assemblies and their applications in electrocatalysis are highlighted, along with discussions of the mechanism of ordering effects. Finally, future research opportunities are provided to encourage further developments in the construction and application of ordered nanostructure assemblies. The ever-growing push for sustainable energy has intensified research on catalytic science. Significant developments have been achieved in state-of-the-art catalyst design from the perspective of catalyst materials. Further promotion can be enabled when rethinking and redesigning the catalyst structure with long-range ordering rather than limited to the catalyst material design. Recently, ordered assembled nanostructures have shown advantages over their disordered counterparts in active site exposure and mass transfer. In this opinion article, we revisit and relate orderly assembly to entropy reduction. Recent advances in the engineering of ordered nanostructure assemblies and their applications in electrocatalysis are highlighted, along with discussions of the mechanism of ordering effects. Finally, future research opportunities are provided to encourage further developments in the construction and application of ordered nanostructure assemblies. describes an ‘entropically driven’ phase transition from an isotropic (orientationally disordered) fluid phase to a nematic (orientationally ordered) phase of nanorods. In Onsager’s theory, the internal energy of the system is zero and only the entropy, coming from orientational degrees of freedom of the nanorods contributes to the free energy of the system. refers to the orientational degree of freedom of nanorods. The orientational ordering occurs accompanied by the orientational entropy change from oriented disorderly to aligned orderly. proceeds at the anode in a proton-exchange-membrane fuel cell (PEMFC); an important half-reaction involved in water splitting. The OER is a four electron–proton coupled reaction involving oxygen–oxygen bond coupling to produce oxygen; under acidic conditions, 2H2O → 4H+ + O2 + 4e−; under basic conditions, 4OH− → 2H2O + O2 + 4e−. occurs in the PEMFC. At the cathode of the PEMFC, oxygen is reduced by a reaction involving four net coupled proton and electron transfers to generate water (½O2 + 2H+ + 2e− → H2O). the spot where the highest reaction rate occurs resulting from the interaction energies of the reactant and the product with the catalyst. Strong binding between reactant and catalyst activates the reactant. Weak binding between product and catalyst is favorable for product removal. These two contradictory trends meet and induce a volcano-like curve of the relationship between reaction rate and binding energy.