Abstract
The ever-increasing world-wide energy consumption and crisis of environmental pollution have aroused enthusiasm on developing high-efficiency and green-clean energy conversion technology. Thermoelectric materials enable an environmentally friendly conversion between heat and electricity, and therefore serve as an optimum candidate for solving the current dilemma and contribute to the carbon-neutral target. Among the thermoelectric family, layered materials have shared a great portion with impressive thermoelectric performance originating from their (quasi-)two-dimensional crystal structure with hierarchical bonding, i.e., strong intralayer and weak interlayer bonds. This structure and bonding feature is believed to be propitious to low lattice thermal conductivity, low-dimensional electrical features, and anisotropic electron and phonon transport behaviors, which offer great opportunity to disentangle the inter-coupled thermoelectric parameters. For those benefits, layered materials emerge endlessly in the field of thermoelectricity and have achieved extensive attention. In this review, we highlight the recent progress in the field of layered thermoelectric materials. The structure and bonding peculiarities of layered thermoelectric materials are outlined. Then, following the classification of single-unit, quasi-double-unit, and double-unit layered thermoelectric materials, the crystal and bonding features in some typical layered thermoelectric materials are discussed, with focus on their current research interest and progresses. The possible mechanisms behind the performance optimization will be analyzed. Finally, some personal views on the prospect of this field, including chemical bond perspective and interlayer electronic transport enhancement are also presented.
Highlights
These fantastic converters are fabricated by weaving a set number of p- and n-type bulk thermoelectric material modules together electrically in series and thermally in parallel [see the schematic structure in Fig. 1(a)].12 According to current theory, a perfect thermoelectric material should be a symphony of high electrical conductivity and Seebeck coefficient, and low thermal conductivity, which is reflected in the dimensionless thermoelectric figure of merit, ZT, defined as[13,14]
Thermoelectric materials that enable direct conversion between heat and electricity could be utilized in waste heat recovery and solid refrigeration, providing an optimum solution for the current energy and environmental crisis and contributing to the carbon-neutral target
The past decades have witnessed a sustained prosperity in the thermoelectric field based on newly developed theories and synthesis methods, well-established modulation strategies, and advanced characterization techniques
Summary
In the past few decades, extensive research has been poured into layered materials, benefiting from their exceptional electrical, thermal,. Scitation.org/journal/are optical and magnetic properties,[57] and the potential application in chemical battery,[58] photocatalysis,[59] electrocatalysis,[60] magnetic refrigeration,[61,62] and thermoelectricity,[24,28,39,44,49,51,52,63,64,65,66,67] representing advanced high-efficiency and green-clean energy conversion materials to mitigate some of the energy and environment problems stated above and build a sustainable future These layered materials are typically composed of strong intralayer-bonded atom planes, separated successively by weak interlayer bonding,[68,69,70] such as van der Waals force or weak ionic bond, leading to a (quasi-)two-dimensional crystal structure with notable bonding strength hierarchy.[65,71,72,73]. STRUCTURE AND CHEMICAL BONDING FEATURES OF LAYERED THERMOELECTRIC MATERIALS (LTMS)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
