Page 135 - Multifunctional Photocatalytic Materials for Energy

Carbon nitride photocatalysts 121

the modified carbon nitride still suffers from a number of restrictions, such as limited
visible light utilization, less active sites, and a high charge carrier recombination rate.
Based on these challenges, endeavors are still required and several strategies are pro-
posed for further studies.
(1) The purpose of exploiting renewable energy is to achieve sustainable development.
Therefore, during the modification process of carbon nitride, less noble metals or toxic
materials should be introduced, even if they significantly boost the photocatalytic perfor-
mances of carbon nitride.
(2) Before experimental modification of carbon nitride, molecular models and reaction pro-
cesses should be optimized by theoretical calculations, which could yield twice the out-
come with half the effort.
(3) Copolymerization, doping, hybridization, morphology, and sensitization could improve the
photocatalytic capability in energy innovation. However, the current output from the use
of modified carbon nitride cannot meet practical requirements. Therefore dual doping or
doping of more elements, ternary hybridization, a variety of nanostructures, and substan-
tial dye sensitization of carbon nitride systems should receive more attention. Moreover,
further studies should integrate these methods.
(4) More energy-generation technologies need to be explored, rather than just focusing on
hydrogen evolution. Carbon nitride-based photocatalysts possess a highly photocatalytic
activity and have multiple applications in energy preparation, and may hold the solutions
for relieving the energy crisis and environmental contamination pressures.

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