Relying on the excellent properties of high-entropy materials
(HEMs),
the high-entropy alloys (HEAs) and high-entropy oxides (HEOs) are
considered as the novel heterogeneous catalysts for the valorization
of biomass feedstock and biomass-derived platform compounds. HEAs
and HEOs are opening up a vast, unknown field of alloy or oxide composition
and can realize the catalyst stability with the rocksalt crystal structure
by means of configurational entropy. In this paper, the general component
and structure of lignocellulosic biomass are concisely introduced.
Then, the fundamental character of HEMs including the inherent merit
and regulatable property as promising catalytic materials is discussed.
Therein, the inherent merits of HEMs are defined as the high entropy
effect in thermodynamics, lattice distortion in the structure, sluggish
diffusion in dynamics, and the cocktail effect in performance; correspondingly,
the regulatable property contains the surface area, the applicability
of the element, and the size of nanoparticles. In addition, the valorization
of biomass feedstocks including the direct pyrolysis of biomass, the
selective transformation of cellulose and hemicelluloses, the utilization
of lignin, and the catalytic valorization of furfural (FUR) and 5-hydroxymethylfurfural
(5-HMF) as the representative biomass-based platform compounds is
discussed, and the obtained valuable reaction products are briefly
summarized. Finally, further research orientations for the selective
volarization of biomass by the use of HEMs as heterogeneous catalysts
is prospected, and the recommendable HEAs and HEOs catalysts including
the potential metallic elements are proposed for the biomass pyrolysis,
the conversion of (hemi)cellulose, and the transformation of lignin,
respectively.