An optoelectronic device includes a flexible substrate, a cerium oxide (CeO.sub.2) layer arranged on the flexible substrate, a single crystal β-III-oxide layer arranged on the CeO.sub.2 layer, and a metallic contact layer arranged on the single crystal β-III-oxide layer.

An optoelectronic device includes a flexible substrate, a cerium oxide (CeO.sub.2) layer arranged on the flexible substrate, a single crystal β-III-oxide layer arranged on the CeO.sub.2 layer, and a metallic contact layer arranged on the single crystal β-III-oxide layer.

An imaging element according to the present disclosure includes: a photoelectric conversion unit that is configured of a first electrode 21 and a photoelectric conversion layer 23A and a second electrode 22 including an organic material being laminated, an inorganic oxide semiconductor material layer 23B is formed between the first electrode 21 and the photoelectric conversion layer 23A, and an inorganic oxide semiconductor material configuring the inorganic oxide semiconductor material layer 23B contains gallium (Ga) atoms, tin (Sn) atoms, zinc (Zn) atoms, and oxygen (O) atoms.

An imaging element according to the present disclosure includes: a photoelectric conversion unit that is configured of a first electrode 21 and a photoelectric conversion layer 23A and a second electrode 22 including an organic material being laminated, an inorganic oxide semiconductor material layer 23B is formed between the first electrode 21 and the photoelectric conversion layer 23A, and an inorganic oxide semiconductor material configuring the inorganic oxide semiconductor material layer 23B contains gallium (Ga) atoms, tin (Sn) atoms, zinc (Zn) atoms, and oxygen (O) atoms.

Photovoltaic devices, and methods of fabricating photovoltaic devices. The photovoltaic devices may include a first electrode, at least one quantum dot layer, at least one semiconductor layer, and a second electrode. The first electrode may include a layer including Cr and one or more silver contacts.

A perovskite-silicon tandem cell capable of absorbing solar radiation with energy lower than that of 1.12 eV, i.e., the bandgap of crystalline silicon—corresponding to the wavelength of 1100 nm. Ho.sup.3+ can absorb photons of wavelength range 1120 to 1190 nm, Tm.sup.3+, 1190 to 1260 nm, and Er.sup.3+, 1145 to 1580 nm, but up-conversion can be achieved using Ho.sup.3+, Tm.sup.3+, and Er.sup.3+-doped metal oxide, such as ZrO.sub.2, in perovskite-silicon tandem solar cells. Doped metal oxides, such as ZrO.sub.2 can also work as selective contacts. Such perovskite-silicon tandem structures can achieve over 30% solar energy conversion efficiency.

A radiation detector is generally described. The detector can comprise a thallium halide (e.g., TlBr) and/or an indium halide. The thallium halide and/or indium halide can be doped with a dopant or a mixture of dopants. The dopant can comprise an alkaline earth metal element, a lanthanide element, and/or an element with an oxidation state of +2. Non-limiting examples of suitable dopants include Ba, Sr, Ca, Mg, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and/or Yb. Radiation detectors, as described herein, may have beneficial properties, including enhanced charge collection and long-term stability.

A radiation detector is generally described. The detector can comprise a thallium halide (e.g., TlBr) and/or an indium halide. The thallium halide and/or indium halide can be doped with a dopant or a mixture of dopants. The dopant can comprise an alkaline earth metal element, a lanthanide element, and/or an element with an oxidation state of +2. Non-limiting examples of suitable dopants include Ba, Sr, Ca, Mg, La, Ce, Pr, Nd, Pm, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, and/or Yb. Radiation detectors, as described herein, may have beneficial properties, including enhanced charge collection and long-term stability.

A semiconductor material having the molecular formula Cu2l2Se6 is provided. Also provided are solid solutions of semiconductor materials having the formulas Cu2lxBr2-xSeyTe6-y and Cu2lxBr2-xSeyS6-y, where 0≤x≤1 and 0≤y≤3. Methods and devices that use the semiconductor materials to convert incident radiation into an electric signal are also provided. The devices include optoelectronic and photonic devices, such as photodetectors, photodiodes, and photovoltaic cells.

A semiconductor material having the molecular formula Cu2l2Se6 is provided. Also provided are solid solutions of semiconductor materials having the formulas Cu2lxBr2-xSeyTe6-y and Cu2lxBr2-xSeyS6-y, where 0≤x≤1 and 0≤y≤3. Methods and devices that use the semiconductor materials to convert incident radiation into an electric signal are also provided. The devices include optoelectronic and photonic devices, such as photodetectors, photodiodes, and photovoltaic cells.