The newly discovered Group-10 transition metal dichalcogenides (TMDs) like PtSe₂ have promising applications in high-performance microelectronic and optoelectronic devices due to their high carrier mobilities, widely tunable bandages and ultrastabilities. However, the optoelectronic performance of broadband PtSe₂ photodetectors integrated with silicon remains undiscovered. Here, we report the successful preparation of large-scale, uniform and vertically grown PtSe₂ films by simple selenization method for the design of a PtSe₂/Si nanowire array heterostructure, which exhibited a very good photoresponsivity of 12.65 A/W, a high specific detectivity of 2.5 × 10¹³ Jones at −5 V and fast rise/fall times of 10.1/19.5 μs at 10 kHz without degradation while being capable of responding to high frequencies of up to 120 kHz. Our work has demonstrated the compatibility of PtSe₂ with the existing silicon technology and ultrabroad band detection ranging from deep ultraviolet to optical telecommunication wavelengths, which can largely cover the limitations of silicon detectors. Further investigation of the device revealed pronounced photovoltaic behavior at 0 V, making it capable of operating as a self-powered photodetector. Overall, this representative PtSe₂/Si nanowire array-based photodetector offers great potential for applications in next-generation optoelectronic and electronic devices.

The layered perovskite-type niobate KCa2Nb3O10 and its derivatives show advantages in several fields, such as templated film growth and (photo)catalysis. Conventional synthesis routes generally yield crystal size smaller than 2 μm. We report a flux synthesis method to obtain KCa2Nb3O10 crystals with significantly larger sizes. By using different flux materials (K2SO4 and K2MoO4), crystals with average sizes of 8 and 20 μm, respectively, were obtained. The KCa2Nb3O10 crystals from K2SO4 and K2MoO4 assisted synthesis were protonated and exfoliated into monolayer nanosheets, and the optimal exfoliation conditions were determined. Using pulsed laser deposition, highly (001)-oriented piezoelectric stacks (SrRuO3/PbZr0.52Ti0.48O3/SrRuO3, SRO/PZT/SRO) were deposited onto Langmuir–Blodgett films of Ca2Nb3O10− (CNO) nanosheets with varying lateral nanosheet sizes on Si substrates. The resulting PZT thin films showed high crystallinity irrespective of nanosheet size. The small sized nanosheets yielded a high longit...