Review of Hybrid 1D/2D Photocatalysts for Light-Harvesting Applications

Among the 17 Sustainable Development Goals (SDGs), we find that SDG7 (clean and affordable energy) and SDG13 (climate action) need to be urgently addressed, also because they are intimately related. Population growth, which has followed an exponential curve for the past two centuries, makes these challenges particularly daunting because growth in energy demand follows the same trend. A variety of renewable energy technologies have been developed to meet the growing need for energy and simultaneously reduce greenhouse gas emissions. Among these, solar energy is considered to be particularly promising because of the relative abundance of sunlight and the progressive reduction in cost. Recent efforts have also focused on developing nanostructured photocatalysts because of their potential for high-performance sustainable energy technologies. Here we review the properties of hybrid one-dimensional/two-dimensional (1D/2D) photocatalysts, which are being widely studied because of several interesting features, including structural (particle/crystallite size, phase composition, specific surface area, surface hydroxyls, and lattice defects) and physical/chemical (chemical stability and optoelectronic, electromagnetic, and photophysical properties) properties. By tuning of the band gap and optimization of the recombination rate of photogenerated charge carriers, these systems can optimize solar energy harvesting beyond the visible spectrum, resulting in an enhanced photocatalytic performance. In particular, we will discuss the following subtopics: classification of the materials' architecture, synthesis techniques, prominent factors that influence the photocatalytic activity, prospects in energy conversion and storage (e.g., H2 production), bacterial disinfection, pollutant degradation, batteries, and CO2 conversion into value-added chemicals. We conclude by describing broad perspectives on future studies of 1D/2D photocatalysts.