Perovskite/silicon tandem solar cells are promising avenues for achieving high‐performance photovoltaics with low costs. However, the highest certified efficiency of perovskite/silicon tandem devices based on economically matured silicon heterojunction technology (SHJ) with fully textured wafer is only 25.2% due to incompatibility between the limitation of fabrication technology which is not compatible with the production‐line silicon wafer. Here, a molecular‐level nanotechnology is developed by designing NiOx/2PACz ([2‐(9H‐carbazol‐9‐yl) ethyl]phosphonic acid) as an ultrathin hybrid hole transport layer (HTL) above indium tin oxide (ITO) recombination junction, to serve as a vital pivot for achieving a conformal deposition of high‐quality perovskite layer on top. The NiOx interlayer facilitates a uniform self‐assembly of 2PACz molecules onto the fully textured surface, thus avoiding direct contact between ITO and perovskite top‐cell for a minimal shunt loss. As a result of such interfacial engineering, the fully textured perovskite/silicon tandem cells obtain a certified efficiency of 28.84% on a 1.2‐cm2 masked area, which is the highest performance to date based on the fully textured, production‐line compatible SHJ. This work advances commercially promising photovoltaics with high performance and low costs by adopting a meticulously designed HTL/perovskite interface.

Multijunction/tandem solar cells have naturally attracted great attention because they are not subject to the Shockley–Queisser limit. Perovskite solar cells are ideal candidates for the top cell in multijunction/tandem devices due to the high power conversion efficiency (PCE) and relatively low voltage loss. Herein, sandwiched gold nanomesh between MoO3 layers is designed as a transparent electrode. The large surface tension of MoO3 effectively improves wettability for gold, resulting in Frank–van der Merwe growth to produce an ultrathin gold nanomesh layer, which guarantees not only excellent conductivity but also great optical transparency, which is particularly important for a multijunction/tandem solar cell. The top MoO3 layer reduces the reflection at the gold layer to further increase light transmission. As a result, the semitransparent perovskite cell shows an 18.3% efficiency, the highest reported for this type of device. When the semitransparent perovskite device is mechanically stacked with a heterojunction silicon solar cell of 23.3% PCE, it yields a combined efficiency of 27.0%, higher than those of both the sub‐cells. This breakthrough in elevating the efficiency of semitransparent and multijunction/tandem devices can help to break the Shockley–Queisser limit.

A metal nanoparticle system has been prepared by 200 Kev Ag+ ion implantation into perfect single crystal SiO2 at room temperature to dose: 6.7×1016/cm2. The system presents quasidual-layer structure: the shallower implanted layer containing noninteracting small Ag nanoparticles and the deeper layer containing interacting large nanoparticles, in which great red shift, about 1 eV, comparing with the plasmon resonance frequency of the noninteracting nanoparticle, can be clearly observed. The red shift is attributed to the multipoles interaction among the high density nanoparticles at external electric field. Moreover, the magnitude of red shift increases with implanted dose.

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The oxidation of methanol on a Pt(111)–(2×2)O surface has been investigated by infrared reflection absorption spectroscopy and temperature-programed desorption. Methanol is dehydrogenated to produce methoxy species in the annealing temperature range from 130 to 170 K. Above 170 K, the reaction proceeds differently, depending on methanol coverage. At the saturation coverage, methanol adsorbates partly desorb molecularly and partly react with precovered oxygen atoms to produce CO, H2, and H2O. No detectable formaldehyde or formate is formed. In contrast, at submonolayer coverages, methoxy species is dehydrogenated to yield formaldehyde at ∼180 K and further oxidized to formate at ∼200 K. Formate is decomposed by 300 K. Defect sites such as steps are not relevant to the formation of the intermediates. When CO is coadsorbed on the surface, it destabilizes the reaction intermediates. The destabilization by coadsorbed CO makes the reaction intermediates short lived so as not to be detectable at high initial coverages of methanol.

Spin-orbit coupled honeycomb magnets with the Kitaev interaction have received a lot of attention due to their potential of hosting exotic quantum states including quantum spin liquids. Thus far, the most studied Kitaev systems are 4d/5d-based honeycomb magnets. Recent theoretical studies predicted that 3d-based honeycomb magnets, including Na2Co2TeO6 (NCTO), could also be a potential Kitaev system. Here, we have used a combination of heat capacity, magnetization, electron spin resonance measurements alongside inelastic neutron scattering (INS) to study NCTO’s quantum magnetism, and we have found a field-induced spin disordered state in an applied magnetic field range of 7.5 T < B (⊥ b-axis) < 10.5 T. The INS spectra were also simulated to tentatively extract the exchange interactions. As a 3d-magnet with a field-induced disordered state on an effective spin-1/2 honeycomb lattice, NCTO expands the Kitaev model to 3d compounds, promoting further interests on the spin-orbital effect in quantum magnets.

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Underdense hydrogenated amorphous silicon (a-Si:H) prepared by plasma-enhanced chemical vapor deposition was used as a passivation layer in silicon heterojunction (SHJ) solar cells. By reducing the thickness of the underdense a-Si:H passivation layer from 15 nm to 5 nm, the open circuit voltage (Voc) of the corresponding SHJ solar cell increased significantly from 724.3 mV to 738.6 mV. For comparison, a widely used transition-zone a-Si:H passivation layer was also examined, but reducing its thickness from 15 nm to 5 nm resulted in a continuous Voc reduction, from 724.1 mV to 704.3 mV. The highest efficiency was achieved using a 5-nm-thick underdense a-Si:H passivation layer. We propose that this advantageous property of underdense a-Si:H reflects its microstructural characteristics. While the porosity of a-Si:H layer enables H penetration into the amorphous network and the a-Si:H/c-Si interface, a high degree of disorder inhibits the formation of the epitaxial layer at the a-Si:H/c-Si interface during post-doping layer deposition.