If you are receiving a signal "from the air" then a resonant input circuit is essentially essential. Also, in real world use an aerial/antenna is required.
Using a signal source with enough voltage may allow use without a resonant circuit, but this will seldom represent reality.
________________________________________________
This paper appears to address your requirements.
Optimization of the Voltage Doubler Stages in an RF-DC Convertor Module for Energy Harvesting
This Avago application note
The Zero Bias
Schottky Detector Diode investigates diode operation at zero bias. Should b read in conjunction with the following application note. Also Avago 1999.
This paper MAY revolutionise your results - or not :-)
All Schottky Diodes are
Zero Bias Detectors
Application Note 988 - Agilent, 1999
________________________________________________
Possible alternative diodes:
The NSVR201MX available ex stock Digikey appears to have a fighting chance of doing the job. It's a single diode.
The NSVR351 is not in stock / 8 weeks lead time but is a dual series diode as is the original 285
Pricing and availability