Electrochemical processes for renewable energy conversion and generation represent promising pathways for lowering our dependence on fossil fuels yet critically depend on the efficiency of applied electrocatalysts, thus attracting considerable interest in the development of highly active and robust electrocatalysts for practical applications. In this review, we discuss recent progress in promoting electrocatalysis for renewable energy technologies based on surface or interface engineering with special emphasis on the geometric structures. We first introduce the state-of-the-art engineering methods for achieving the desired surface or interface and correlate these structures with their catalytic performances. Then, we describe classic examples of rational surfaces and interfaces for tuning metallic nanomaterials for several key catalytic reactions in renewable energy technologies, including the hydrogen evolution and oxidation reactions, oxygen reduction and evolution reactions, methanol oxidation reaction, and electrochemical carbon dioxide reduction. Finally, we provide personal perspectives to highlight the challenges and opportunities for metallic electrocatalysts in terms of catalysis-driven surface and interface engineering.

Co3O4/Co2MnO4 nanocomposites, derived from a single-source CoMn-layered double hydroxide precursor, exhibit excellent bifunctional oxygen electrode activities for both oxygen reduction and evolution reactions, which can be attributed to the large specific surface area and well-dispersed heterogeneous structure of the nanocomposites.

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A highly active bifunctional electrocatalyst for oxygen reduction and evolution reactions was developed based on nanocarbon-intercalated and Fe–N-codoped graphene materials.

Analyses of diatoms, grain size, magnetic susceptibility, total organic carbon, and total nitrogen were applied to a 9.26 m long sediment core, spanning the last 12.2 kyr, from a small treeline lake (Tiancai Lake, ~3898 m a.s.l.) in southwest China. Diatom assemblages are dominated by Cyclotella distinguenda, Aulacoseira species, and small fragilarioid taxa, all of which are sensitive to changes in water pH and light conditions that are probably related to vegetation development and runoff processes triggered by variations in the Asian monsoon. High abundances of C. distinguenda and Pseudostaurosira brevistriata reflected cold and dry climates during the Late Glacial (12.2-11.4 kyr BP). In the early Holocene (11.4-9.4 kyr BP), a steep decline in C. distinguenda and a visible increase in Aulacoseira alpigena responded to a strengthening monsoon intensity. The persistent increases in A. alpigena mirrored strong monsoon intensity in the middle Holocene (9.4-4.6 kyr BP). After 4.6 kyr BP, the reduction of A. alpigena was related to weak monsoon intensity in the late Holocene. The main trends of diatom evolution show a general correspondence to variations in solar insolation. Three visible excursions, with an increase in P. brevistriata and a drop in A. alpigena, centered at around 8.4, 2.5, and 0.3 kyr BP, correlate with low sunspot numbers and known cold events in the North Atlantic. Some similarities and correlations between the Holocene diatom data, the North Atlantic record, and solar insolation indicate that variations in the Asian monsoon response to changes in solar forcing and the North Atlantic climate.

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Porous organic polymers (POPs), known for its high surface area and abundant porosity, can be easily designed and constructed at the molecular level. The POPs offer confined molecular spaces for the interplay of photons, excitons, electrons and holes, therefore featuring great potential in catalysis. In this review, a brief summary on the recent development of some current state-of-the-art POPs for photocatalytic water splitting and their design principles and synthetic strategies as well as relationship between structure and photocatalytic hydrogen or oxygen evolution performance are presented. Future prospects including research directions are also proposed, which may provide insights for developing POPs for photocatalytic water splitting with our expectations.

Molecular macrocycles are very promising electrocatalysts for the reduction of carbon dioxide into value-added chemicals. Up to now, most of these catalysts produced only C1 products. We report here that...