4 CONCLUSIONS AND PERSPECTIVES
This review underscores the critical role of interface engineering in
optimizing the efficiency of PEC catalysts, providing valuable insights
into recent research trends and contributing to the global pursuit of
carbon neutrality. Interface engineering emerges as a pivotal strategy,
optimizing cocatalysts, functional engineering, and defect engineering
to overcome existing limitations. Noble metal cocatalysts, such as Ag
and Au, are seamlessly integrated with plasmonic materials to induce
surface plasmon resonance, thereby enhancing light absorption and
catalytic efficiency for photocatalytic CO2 reduction.
This enhancement is evident in various studies utilizing diverse
plasmonic nanostructures and synthesis methods. When semiconductor
materials are integrated with various cocatalysts, including noble
metals, cobalt-based molecular catalysts, and non-noble metal materials,
they demonstrate promising advancements in enhancing efficiency,
selectivity, and stability for photocatalytic CO2reduction. Semiconductor heterojunctions, encompassing type-I, type-II,
and Schottky barrier junctions, play a pivotal role in enhancing PEC
CO2RR by facilitating the separation of photogenerated
electrons and holes through distinct band structures. Nanostructure
engineering further augments photocathode performance by manipulating
materials on the nanometer scale, employing structures such as nanorods,
nanowires, and core/shell configurations. Defect engineering, involving
native point defects like vacancies and interstitials, influences
catalytic, electrical, and optical properties. These defects, classified
as 0D (point defects), 1D (line defects), 2D (interface defects), and 3D
(bulk defects), enhance photoactivity in heterogeneous catalysis.
Despite numerous research outcomes, interface engineering still requires
further studies, and researchers posit that several topics will need
more in-depth exploration.
· The PEC process based on interface engineering often involves complex
procedures and expensive equipment, necessitating the development of
more streamlined and cost-effective approaches.
· Extensive research is required to assess the long-term performance,
stability, and durability of catalysts used in CO2reduction experiments, particularly in challenging environmental
conditions.
· Current investigations into PEC CO2RR predominantly
yield C1 products; therefore, a critical need exists for
comprehensive studies focusing on C2+ products, which
offer higher value-added potential.
· To facilitate the commercialization of catalysts, validating their
performance on a larger scale within the existing laboratory setting is
essential. This includes emphasizing creating and evaluating larger-area
catalysts when implementing interface engineering technology.
Researchers have made significant strides in addressing these
challenges. Notably, PEC co-catalysts have demonstrated potential in
improving PEC system performance by effectively capturing and
segregating photogenerated charge carriers while minimizing
recombination. However, the implementation of these co-catalysts still
encounters diverse challenges. Common issues associated with PEC systems
exist, along with strategies aimed at overcoming them. The mere
application of a co-catalyst onto the photoelectrode surface proves
insufficient for constructing a robust and efficient PEC cell.
Consequently, engineering the interface between co-catalysts and the
photoelectrode surface becomes imperative for facilitating the desired
reactions. Strategies to enhance PEC efficiency and stability involve
the incorporation of suitable interlayers, transport layers, and
electron-blocking layers. While co-catalysts play a pivotal role in
promoting desired PEC reactions, their inefficient utilization can
hinder overall performance. To address this concern, facile strategies
such as optimizing co-catalyst loading and integrating them into
composite materials need exploration. This approach aims to improve the
surface area and active sites of the co-catalysts. Additionally,
designing efficient configurations, such as core/shell structures with
multijunction components, represents an effective means of enhancing
co-catalyst utilization and overall efficiency. In summary, this review
paper explores current trends in PEC CO2 reduction
research from the perspective of interface engineering. By identifying
these trends, the paper aims to make a significant contribution to the
broader field of carbon dioxide reduction research.