**3. Conclusions**

As summarized in this mini-review, an ideal fuel-cell electrode should be porous, and possess high conductivity, accessible electrochemical surface sites, and improved charge and mass transfer pathways. Defect engineering, which involves manipulating the type, concentration, or spatial distribution of heteroatoms and size-controlled vacancies within a solid, along with materials processing approaches, such as three-dimensional structure assembly and surface metal complexation methodologies, has demonstrated its potential to tackle the challenges triggered by energy conversion concerns in direct alcohol fuel cells. With continuous progress on the knowledge gained from the engineered nanosheets, a transition from bench-scale nanotechnology to pilot plant manufactures and, eventually, commercial production is likely to be configured.
