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<jats:p> Inserting an ultrathin low-conductivity interlayer between the absorber and transport layer has emerged as an important strategy for reducing surface recombination in the best perovskite solar cells. However, a challenge with this approach is a trade-off between the open-circuit voltage ( <jats:italic>V</jats:italic> <jats:sub>oc</jats:sub> ) and the fill factor (FF). Here, we overcame this challenge by introducing a thick (about 100 nanometers) insulator layer with random nanoscale openings. We performed drift-diffusion simulations for cells with this porous insulator contact (PIC) and realized it using a solution process by controlling the growth mode of alumina nanoplates. Leveraging a PIC with an approximately 25% reduced contact area, we achieved an efficiency of up to 25.5% (certified steady-state efficiency 24.7%) in p-i-n devices. The product of <jats:italic>V</jats:italic> <jats:sub>oc</jats:sub> × FF was 87.9% of the Shockley-Queisser limit. The surface recombination velocity at the p-type contact was reduced from 64.2 to 9.2 centimeters per second. The bulk recombination lifetime was increased from 1.2 to 6.0 microseconds because of improvements in the perovskite crystallinity. The improved wettability of the perovskite precursor solution allowed us to demonstrate a 23.3% efficient 1-square-centimeter p-i-n cell. We demonstrate here its broad applicability for different p-type contacts and perovskite compositions. </jats:p>

<jats:p>Ammonia is a critical component in fertilizers, pharmaceuticals, and fine chemicals and is an ideal, carbon-free fuel. Recently, lithium-mediated nitrogen reduction has proven to be a promising route for electrochemical ammonia synthesis at ambient conditions. In this work, we report a continuous-flow electrolyzer equipped with 25–square centimeter–effective area gas diffusion electrodes wherein nitrogen reduction is coupled with hydrogen oxidation. We show that the classical catalyst platinum is not stable for hydrogen oxidation in the organic electrolyte, but a platinum-gold alloy lowers the anode potential and avoids the decremental decomposition of the organic electrolyte. At optimal operating conditions, we achieve, at 1 bar, a faradaic efficiency for ammonia production of up to 61 ± 1% and an energy efficiency of 13 ± 1% at a current density of −6 milliamperes per square centimeter.</jats:p>

<jats:p>Plate motion on shallow subduction megathrusts is accommodated by a spectrum of tectonic slip modes. However, the frictional properties and conditions that sustain these diverse slip behaviors remain enigmatic. Frictional healing is one such property, which describes the degree of fault restrengthening between earthquakes. We show that the frictional healing rate of materials entrained along the megathrust at the northern Hikurangi margin, which hosts well-characterized recurring shallow slow slip events (SSEs), is nearly zero (&lt;0.0001 per decade). These low healing rates provide a mechanism for the low stress drops (&lt;50 kilopascals) and short recurrence times (1 to 2 years) characteristic of shallow SSEs at Hikurangi and other subduction margins. We suggest that near-zero frictional healing rates, associated with weak phyllosilicates that are common in subduction zones, may promote frequent, small-stress-drop, slow ruptures near the trench.</jats:p>

<jats:p>After 2 years in Washington, DC, Alondra Nelson is returning to Princeton. A highly decorated sociologist who has written and studied extensively on the intersection of genetics and race, she was appointed by President Joe Biden as deputy director for science and society in the Office of Science and Technology Policy (OSTP) in 2021. The following year, when Eric Lander was removed as the head of that office, Nelson stepped in as its interim director until Arati Prabhakar was named permanent director 8 months later. I recently spoke with Nelson, about a range of issues, from scientific publishing to artificial intelligence. She clearly leaves behind a legacy of science policy-making that encourages equity.</jats:p>

<jats:p>Genes reveal striking diversity within similar ice age cultures</jats:p>

<jats:p>A “creative” strategy to keep crops healthy borrows key pathogen detectors from the animal immune system</jats:p>

<jats:p>Humans and domestic species far outweigh other mammals</jats:p>

<jats:p>Women and Black researchers are less likely to hold multiple NIH grants</jats:p>

<jats:p>Implicit bias can degrade health care. Now, researchers are finding new ways to recognize and mitigate it</jats:p>