Pulp fact: Paper batteries to power laptops, drive cars

Ordinary paper could one day be used as a lightweight battery to power the devices that are now enabling the printed word to be eclipsed by email, ebooks and online news.

Scientists at Stanford University in California reported on Monday that they have successfully turned paper coated with ink made of silver and carbon nanomaterials into a “paper battery” that holds promise for new types of lightweight, high-performance energy storage.

The same feature that helps ink adhere to paper allows it to hold onto the single-walled carbon nanotubes and silver nanowire films. Earlier research found that silicon nanowires could be used to make batteries 10 times as powerful as lithium-ion batteries now used to power devices such as laptops.

“Taking advantage of the mature paper technology, low cost, light and high-performance energy-storage are realized by using conductive paper as current collectors and electrodes,” the scientists said.

This type of battery could be useful in powering electric or hybrid vehicles, would make electronics lightweight and long lasting, and might even lead someday to paper electronics, the scientists said.

Battery weight and life have been an obstacle to commercial viability of electric-powered cars and trucks.

“Society really needs a low-cost, high-performance energy storage device, such as batteries and simple supercapacitors,” Stanford assistant professor of materials science and engineering and paper co-author Yi Cui said.

Cui said in an email that in addition to being useful for portable electronics and wearable electronics, “Our paper supercapacitors can be used for all kinds of applications that require instant high power.” Peidong Yang, professor of chemistry at the University of California-Berkeley, said the technology could be commercialized within a short time.

Antidepressants can change personality

Apart From Easing Symptoms, Drugs Can Even Turn People Into Extroverts, Say Researchers.

Taking an antidepressant can lead to significant personality changes, likely for the better. Antidepressants may go well beyond just easing the symptoms of depression; they may also make people less neurotic, US researchers said.

The study of people who took GlaxoSmithKline’s Paxil, known generically as paroxetine, suggests the drug may treat factors such as neuroticism that make a person more likely to be depressed in the first place.

“Our data suggests that modern antidepressants work partly by correcting key personality risk factors of depression,” said Tony Tang, a psychology professor at Northwestern University in Evanston, Illinois, whose study appears in Archives of General Psychiatry.

People who are neurotic tend to experience negative emotions and be emotionally unstable, often experiencing wide mood swings in a day. “It’s the basic tendency toward having negative emotions,” Tang said.

He said many studies have suggested that people who are highly neurotic have a higher risk of becoming depressed.

There is also some suggestion that people who are extroverts — those who tend to be both socially outgoing and have a more positive outlook on life — are less likely to become depressed, Tang said. Both personality traits are affected by levels of the brain chemical serotonin, which is the chief target of a large class of antidepressants known as selective serotonin reuptake inhibitors, or SSRIs.

Tang and colleagues looked to see if the SSRI Paxil, also sold under the brand Seroxat, had any effect beyond just treating depression symptoms. They gave the drug to 120 volunteers with depression and compared their experiences to 60 people who underwent a type of therapy known as cognitive behavioral therapy and another group of 60 who took a placebo.

Their personalities and depression symptoms were assessed before and after treatment.

After 12 weeks, all participants saw improvements in their depression symptoms, but those who took Paxil also saw significant drop in their neuroticism, and a marked increase in extroversion compared with those in the other groups.

“Patients taking paroxetine reported 6.8 times as much change on neuroticism and 3.5 times as much change on extroversion as placebo patients matched for depression improvement,” the authors wrote. “Those are very dramatic, notable changes,” Tang said.

“At the beginning of the treatment, they were way out there. Their neuroticism was abnormally high. By the end of treatment, they moved back into the boundary of the normal range.”

He said many of the drugs in the SSRI class work largely the same way are likely to have the same effect.

Ian Cook of the David Geffen School of Medicine at the University of California Los Angeles, who was not part of the study, said the findings may cause some doctors to rethink their assumptions about how antidepressants work. “The conventional wisdom has been for many years that the changes in personality that one sees during treatment tend to be thought of as a reflection of getting the depression under control,” he said.