In the cover picture, we adapt
the ideal from "Journey to the West," one of Chinese four literary
classics. The ancient Chinese mythical character, Monkey King, holds a treasure
in his hand, which represents the catalysts with well-defined interface. CO2 is blown out from the mouth of Monkey King, then goes through the catalyst
interface, and finally is converted into high value-added chemicals like CH4,
CH3OH and CO. This well describes the focus of our paper titled “Progress
and Understanding on Catalysts with Well-defined Interface for Boosting CO2 Conversion”.
Ferroelectric materials, characterized by the
switchable spontaneous polarization (Ps)
through reversing the directions of external electric field, exhibit versatile
physical attributes that have been extensively used for practical device
applications. Two-dimensional (2D) organic-inorganic hybrid perovskites
are recently emerging as a robust family of candidate ferroelectrics, termed
ferroelectric semiconductors. In particular, the coexistence and/or coupling of
ferroelectric polarization with their semiconducting properties enables new
physical concepts, thus providing a potential platform for the development of
new multifunctional optoelectronic devices. This review primarily describes the
structural origin of symmetry breaking for generating ferroelectric orders in
2D hybrid perovskites, and then presents the combination of ferroelectric Ps with other semiconducting
optoelectronic activities. Regarding the emergence of new photoelectric behaviors,
the prospects for this 2D family of ferroelectric semiconductors are further
discussed, along with their development tendency for the future photoelectronic
device applications.