The present invention relates to a tandem solar cell which comprises: a perovskite solar cell comprising a perovskite absorption layer; a silicon solar cell placed under the perovskite solar cell; a junction layer placed between the perovskite solar cell and the silicon solar cell; an upper electrode placed on the perovskite solar cell; and a lower electrode placed under the silicon solar cell.

The present invention relates to a tandem solar cell which comprises: a perovskite solar cell comprising a perovskite absorption layer; a silicon solar cell placed under the perovskite solar cell; a junction layer placed between the perovskite solar cell and the silicon solar cell; an upper electrode placed on the perovskite solar cell; and a lower electrode placed under the silicon solar cell.

A monolithic metamorphic multi-junction solar cell comprising a first III-V subcell and a second III-V subcell and a third III-V subcell and a fourth Ge subcell, wherein the subcells are stacked on top of each other in the indicated order, and the first subcell forms the topmost subcell, and a metamorphic buffer is formed between the third subcell and the fourth subcell and all subcells each have an n-doped emitter layer and a p-doped base layer, and the emitter layer of the second subcell is greater than the base layer.

A monolithic metamorphic multi-junction solar cell comprising a first III-V subcell and a second III-V subcell and a third III-V subcell and a fourth Ge subcell, wherein the subcells are stacked on top of each other in the indicated order, and the first subcell forms the topmost subcell, and a metamorphic buffer is formed between the third subcell and the fourth subcell and all subcells each have an n-doped emitter layer and a p-doped base layer, and the emitter layer of the second subcell is greater than the base layer.

The present disclosure relates to a photovoltaic (PV) device that includes a first junction constructed with a first alloy and having a bandgap between about 1.0 eV and about 1.5 eV, and a second junction constructed with a second alloy and having a bandgap between about 0.9 eV and about 1.3 eV, where the first alloy includes III-V elements, the second alloy includes III-V elements, and the PV device is configured to operate in a thermophotovoltaic system having an operating temperature between about 1500° C. and about 3000° C.

The present disclosure relates to a photovoltaic (PV) device that includes a first junction constructed with a first alloy and having a bandgap between about 1.0 eV and about 1.5 eV, and a second junction constructed with a second alloy and having a bandgap between about 0.9 eV and about 1.3 eV, where the first alloy includes III-V elements, the second alloy includes III-V elements, and the PV device is configured to operate in a thermophotovoltaic system having an operating temperature between about 1500° C. and about 3000° C.

Optically-thin, quantum-structured solar cells incorporating III-V quantum wells or quantum dots have the potential to revolutionize the performance of photovoltaic devices. Enhanced spectral response characteristics have been widely demonstrated in both quantum well and quantum dot solar cells using a variety of different III-V materials. To fully leverage the extended spectral response of quantum-structured solar cells, new device designs are disclosed that can both maximize the current generating capability of the limited volume of narrow band gap material and minimize the unwanted carrier recombination that degrades the voltage output.

A multijunction solar cell including a growth substrate; a graded interlayer disposed over the growth substrate, a plurality of subcells disposed over the graded interlayer including a second solar subcell disposed over and lattice mismatched with respect to the growth substrate, and at least a third solar subcell disposed over the second subcell; the grading interlayer including a plurality of N step-graded sublayers (where N is an integer and the value of N is 1<N<10), wherein each successive sublayer has an incrementally greater lattice constant than the sublayer below it and grown in such a manner that each sublayer is fully relaxed, a distributed Bragg reflector (DBR) layer over the grading interlayer and an upper solar subcell disposed over the third solar subcell, a band gap in the range of 1.95 to 2.20 eV, and composed of a semiconductor compound including at least indium, aluminum and phosphorus.

A multijunction solar cell including a growth substrate; a graded interlayer disposed over the growth substrate, a plurality of subcells disposed over the graded interlayer including a second solar subcell disposed over and lattice mismatched with respect to the growth substrate, and at least a third solar subcell disposed over the second subcell; the grading interlayer including a plurality of N step-graded sublayers (where N is an integer and the value of N is 1<N<10), wherein each successive sublayer has an incrementally greater lattice constant than the sublayer below it and grown in such a manner that each sublayer is fully relaxed, a distributed Bragg reflector (DBR) layer over the grading interlayer and an upper solar subcell disposed over the third solar subcell, a band gap in the range of 1.95 to 2.20 eV, and composed of a semiconductor compound including at least indium, aluminum and phosphorus.

A multijunction solar cell including an upper first solar subcell having a first band gap and positioned for receiving an incoming light beam; a second solar subcell disposed below and adjacent to and lattice matched with said upper first solar subcell, and having a second band gap smaller than said first band gap; wherein at least one of the solar subcells has a graded band gap throughout the thickness of at least a portion of the active layer.