posted on 2024-02-07, 07:08authored byChunlin Hao, Shukui Wu, Guibao Guo, Shengli An
Production of alkane fuels from fatty acids by photocatalytic
decarboxylation
is presently challenging due to low product output efficiency. Here,
we report a high-efficiency photocatalytic decarboxylation route,
achieving the transformation of high-concentration bioderived long-chain
fatty acids to C1-shortened n-alkanes only by using
the in situ heat from the photothermal conversion of Fe3O4. Through the use of high-boiling-point n-alkane solvents for getting the maximum reaction temperature, the
single output concentration of Cn–1n-alkane was upgraded from a traditional far less
than mmol/L level to the unprecedented mol/L level. We suggest that
the heat enhances the strain of aimed C–COO– bond by forcing the standing C-chain down at room temperature onto
the Fe3O4 surface, leading photoinduced hole–electron
pair easily to be close to and react with the energy-storing C–COO– bond. Meanwhile, the photogenerated electron consumption
can shift from conventional PCET of the photo-Koble reaction into
a stepwise pathway to form a more favorable carbanion (R–) intermediate that reacting with H+ into RH is highly
accelerated with lifting the temperature. Our findings open a new
way to upgrade the output efficiency of photocatalytic decarboxylation
reaction by reusing the vast majority of incident light energy in
a heat form.