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[Display omitted] • TZO CNRs with controllable morphology and composition through a traditional metal assisted CVD technique were fabricated. • Three self-powered photodetectors were fabricated using TZO CNRs/Si heterojunction which could detect UV-NIR selectively. • IV-characteristics on illumination of UV and/or NIR radiation show good and fast response. Tellurium dioxide (TeO 2) doped zinc oxide (ZnO) composite nanorods (TZO CNRs) were first synthesized by chemical vapor deposition method on a p-type silicon substrate covered by a sputtered gold (Au) film. The morphologies, structures, compositions and optical properties of the TZO CNRs can be modulated with the TeO 2 content. Three typical self-powered TZO CNRs/Si heterojunction photodetectors named device 1, 2 and 3 according to the different TeO 2 contents and TZO CNR morphologies are designed. Device 1 based on 1.81 At% Te content TZO CNRs can detect UV lights with wavelength from 290 to 380 nm and showed a responsivity of 4.3 mA/W, a detectivity of 1.1 × 1012 cmHz1/2W−1 upon exposure to 370 nm light at a zero-bias voltage. Device 2 based on 5.86 At% Te content TZO CNRs is found to be selectively sensitive to UV and NIR lights. Device 3 based on 9.23 At% Te content TZO CNRs is found to be also selectively sensitive to NIR lights. Its most sensitive wavelength is 1040 nm with responsivity and detectivity of 24.6 mA/W and 4.12 × 1012 cmHz1/2W−1, respectively. In addition, the mechanism that led to their typical properties of these devices are also elucidated. [ABSTRACT FROM AUTHOR]

Light-emitting diodes (LEDs) based on ZnO were fabricated on a p -Si substrate by using a pulsed laser deposition system. Significant electroluminescence (EL) improvement was demonstrated with the insertion of an HfO 2 electron blocking layer (EBL) in n -ZnO/ p -Si heterojunctions. Distinct near-band-edge emission at around 392 nm accompanying by a broadly strong visible emission was achieved when a proper thickness of HfO 2 EBL was used. Current-voltage and capacitance-voltage measurements confirmed that a proper thickness of the HfO 2 EBL can effectively balance the injection of electrons and holes, resulting in an increase of radiative recombination in the ZnO active layer and thus enhancing the EL performance of the devices. Five independent emissions corresponding to five different transition processes were proposed to clarify the EL origination of the n -ZnO/HfO 2 / p -Si heterojunction LEDs by Gaussian deconvolutions. It is hoped that results in this work should be helpful for the development of ZnO-based LEDs that can integrate ZnO with the Si planar technology. [ABSTRACT FROM AUTHOR]