“…For instance, the monolayer Janus TMDCs MXY (M = Mo(W), Zr(Hf); X a Y = S, Se, Te), which can be obtained by replacing one of the S(Se, Te) atom layers in monolayer MX(Y) 2 , have been synthesized successfully through chemical vapor deposition (CVD) in experiments. [22][23][24][25][26] Interestingly, more photo-excited carriers tend to be separated than recombination due to the out-of-plane polarization induced by disrupted lattice inversion and mirror symmetry, which eventually improves and enriches their actual performances in photovoltaic related devices, correspondingly. 22,26 More strikingly, the performances of these single 2D crystals in photovoltaics can be further improved by constructing them into heterostructures.…”